Voquezna

Drug overview for VOQUEZNA (vonoprazan fumarate):

Generic name: vonoprazan fumarate (von-OH-pra-zan)
Drug class: Peptic Ulcer Agents
Therapeutic class: Gastrointestinal Therapy Agents

Vonoprazan is a potassium-competitive acid blocker.

No enhanced Uses information available for this drug.

DRUG IMAGES

VOQUEZNA 20 MG TABLET

The following indications for VOQUEZNA (vonoprazan fumarate) have been approved by the FDA:

Indications:
Erosive esophagitis
Gastroesophageal reflux disease
H. pylori gastrointestinal tract infection

Professional Synonyms:
Gastro-esophageal reflux
GE reflux disease

Dosing information for VOQUEZNA
DRUG LABEL	DOSING TYPE	DOSING INSTRUCTIONS
VOQUEZNA 10 MG TABLET	Maintenance	Adults take 1 tablet (10 mg) by oral route once daily
VOQUEZNA 20 MG TABLET	Maintenance	Adults take 1 tablet (20 mg) by oral route once daily

The following drug interaction information is available for VOQUEZNA (vonoprazan fumarate):

Contraindicated
Severe
Moderate

There are 2 contraindications. These drug combinations generally should not be dispensed or administered to the same patient. A manufacturer label warning that indicates the contraindication warrants inclusion of a drug combination in this category, regardless of clinical evidence or lack of clinical evidence to support the contraindication.

Drug Interaction	Drug Names
Rilpivirine/Proton Pump Inhibitors SEVERITY LEVEL: 1-Contraindicated Drug Combination: This drug combination is contraindicated and generally should not be dispensed or administered to the same patient. MECHANISM OF ACTION: Rilpivirine requires an acidic medium for absorption. The proton pump inhibitor induced decrease in gastric pH may result in a decrease in rilpivirine absorption.(1) CLINICAL EFFECTS: Concurrent use of a proton pump inhibitor may result in decreased levels and effectiveness of rilpivirine, as well as the development of resistance.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The US manufacturer of rilpivirine states that concurrent use of proton pump inhibitors is contraindicated.(1) When substituting antacids for proton pump inhibitors in patients maintained on rilpivirine, administer the antacid at least 2 hours before or 4 hours after rilpivirine.(1) When substituting H2 antagonists for proton pump inhibitors in patients maintained on rilpivirine, administer the H2 antagonist at least 12 hours before or 4 hours after rilpivirine.(1) DISCUSSION: In a study in 16 subjects, omeprazole (20 mg daily) decreased the maximum concentration (Cmax), area-under-curve (AUC), and minimum concentration (Cmin) of rilpivirine (150 mg daily) by 40%, 40%, and 33%, respectively. The Cmax and AUC of omeprazole decreased by 14% and 14%, respectively.(1) In a study in 24 subjects, famotidine (40 mg single dose) administered 12 hours before a single dose of rilpivirine (150 mg) had no significant effect on rilpivirine Cmax or AUC.(1) In a study in 23 subjects, famotidine (40 mg single dose) administered 2 hours before a single dose of rilpivirine (150 mg) decreased the rilpivirine Cmax and AUC by 85% and 76%, respectively.(1) In a study in 24 subjects, famotidine (40 mg single dose) administered 4 hours after a single dose of rilpivirine (150 mg) increased the rilpivirine Cmax and AUC by 21% and 13%, respectively.(1)	COMPLERA, EDURANT, JULUCA, ODEFSEY
Lemborexant (Greater Than 5 mg)/Weak CYP3A4 Inhibitors SEVERITY LEVEL: 1-Contraindicated Drug Combination: This drug combination is contraindicated and generally should not be dispensed or administered to the same patient. MECHANISM OF ACTION: Inhibitors of CYP3A4 may inhibit the metabolism of lemborexant.(1) CLINICAL EFFECTS: Concurrent use of an inhibitor of CYP3A4 may result in increased levels of and effects from lemborexant, including somnolence, fatigue, CNS depressant effects, daytime impairment, headache, and nightmare or abnormal dreams.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The maximum recommended dose of lemborexant with concurrent use of a weak CYP3A4 inhibitors should not exceed 5 mg per dose.(1) DISCUSSION: Lemborexant is a CYP3A4 substrate. In a PKPB model, concurrent use of lemborexant with itraconazole increased area-under-curve (AUC) and concentration maximum (Cmax) by 3.75-fold and 1.5-fold, respectively. Concurrent use of lemborexant with fluconazole increased AUC and Cmax by 4.25-fold and 1.75-fold, respectively.(1) Weak inhibitors of CYP3A4 include: alprazolam, amiodarone, amlodipine, asciminib, azithromycin, Baikal skullcap, belumosudil, berberine, bicalutamide, blueberry, brodalumab, cannabidiol, capivasertib, chlorzoxazone, cilostazol, cimetidine, ciprofloxacin, clotrimazole, cranberry, cyclosporine, daclatasvir, daridorexant, delavirdine, dihydroberberine, diosmin, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lapatinib, larotrectinib, lazertinib, leflunomide, levamlodipine, linagliptin, lomitapide, lurasidone, mavorixafor, olaparib, osilodrostat, palbociclib, pazopanib, peppermint oil, piperine, propiverine, propofol, ranitidine, ranolazine, remdesivir, resveratrol, roxithromycin, rucaparib, selpercatinib, simeprevir, sitaxsentan, skullcap, suvorexant, teriflunomide, ticagrelor, tolvaptan, trofinetide, viloxazine, and vonoprazan.(1,2)	DAYVIGO

Drug Interaction

Drug Names

Rilpivirine/Proton Pump Inhibitors

SEVERITY LEVEL: 1-Contraindicated Drug Combination: This drug combination is contraindicated and generally should not be dispensed or administered to the same patient.

MECHANISM OF ACTION: Rilpivirine requires an acidic medium for absorption. The proton pump inhibitor induced decrease in gastric pH may result in a decrease in rilpivirine absorption.(1)

CLINICAL EFFECTS: Concurrent use of a proton pump inhibitor may result in decreased levels and effectiveness of rilpivirine, as well as the development of resistance.(1)

PREDISPOSING FACTORS: None determined.

PATIENT MANAGEMENT: The US manufacturer of rilpivirine states that concurrent use of proton pump inhibitors is contraindicated.(1) When substituting antacids for proton pump inhibitors in patients maintained on rilpivirine, administer the antacid at least 2 hours before or 4 hours after rilpivirine.(1) When substituting H2 antagonists for proton pump inhibitors in patients maintained on rilpivirine, administer the H2 antagonist at least 12 hours before or 4 hours after rilpivirine.(1)

DISCUSSION: In a study in 16 subjects, omeprazole (20 mg daily) decreased the maximum concentration (Cmax), area-under-curve (AUC), and minimum concentration (Cmin) of rilpivirine (150 mg daily) by 40%, 40%, and 33%, respectively. The Cmax and AUC of omeprazole decreased by 14% and 14%, respectively.(1) In a study in 24 subjects, famotidine (40 mg single dose) administered 12 hours before a single dose of rilpivirine (150 mg) had no significant effect on rilpivirine Cmax or AUC.(1)

In a study in 23 subjects, famotidine (40 mg single dose) administered 2 hours before a single dose of rilpivirine (150 mg) decreased the rilpivirine Cmax and AUC by 85% and 76%, respectively.(1) In a study in 24 subjects, famotidine (40 mg single dose) administered 4 hours after a single dose of rilpivirine (150 mg) increased the rilpivirine Cmax and AUC by 21% and 13%, respectively.(1)

COMPLERA, EDURANT, JULUCA, ODEFSEY

Lemborexant (Greater Than 5 mg)/Weak CYP3A4 Inhibitors

SEVERITY LEVEL: 1-Contraindicated Drug Combination: This drug combination is contraindicated and generally should not be dispensed or administered to the same patient.

MECHANISM OF ACTION: Inhibitors of CYP3A4 may inhibit the metabolism of lemborexant.(1)

CLINICAL EFFECTS: Concurrent use of an inhibitor of CYP3A4 may result in increased levels of and effects from lemborexant, including somnolence, fatigue, CNS depressant effects, daytime impairment, headache, and nightmare or abnormal dreams.(1)

PREDISPOSING FACTORS: None determined.

PATIENT MANAGEMENT: The maximum recommended dose of lemborexant with concurrent use of a weak CYP3A4 inhibitors should not exceed 5 mg per dose.(1)

DISCUSSION: Lemborexant is a CYP3A4 substrate. In a PKPB model, concurrent use of lemborexant with itraconazole increased area-under-curve (AUC) and concentration maximum (Cmax) by 3.75-fold and 1.5-fold,

respectively. Concurrent use of lemborexant with fluconazole increased AUC and Cmax by 4.25-fold and 1.75-fold,

respectively.(1) Weak inhibitors of CYP3A4 include: alprazolam, amiodarone, amlodipine, asciminib, azithromycin, Baikal skullcap, belumosudil, berberine, bicalutamide, blueberry, brodalumab, cannabidiol, capivasertib, chlorzoxazone, cilostazol, cimetidine, ciprofloxacin, clotrimazole, cranberry, cyclosporine, daclatasvir, daridorexant, delavirdine, dihydroberberine, diosmin, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lapatinib, larotrectinib, lazertinib, leflunomide, levamlodipine, linagliptin, lomitapide, lurasidone, mavorixafor, olaparib, osilodrostat, palbociclib, pazopanib, peppermint oil, piperine, propiverine, propofol, ranitidine, ranolazine, remdesivir, resveratrol, roxithromycin, rucaparib, selpercatinib, simeprevir, sitaxsentan, skullcap, suvorexant, teriflunomide, ticagrelor, tolvaptan, trofinetide, viloxazine, and vonoprazan.(1,2)

DAYVIGO

There are 20 severe interactions. These drug interactions can produce serious consequences in most patients. Actions required for severe interactions include, but are not limited to, discontinuing one or both agents, adjusting dosage, altering administration scheduling, and providing additional patient monitoring. Review the full interaction monograph for more information.

Drug Interaction	Drug Names
Posaconazole Suspension/H2 Antagonists; Proton Pump Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: H2 antagonists and proton pump inhibitors (PPIs) increase the stomach pH, possibly reducing gastrointestinal absorption of posaconazole suspension. CLINICAL EFFECTS: Concurrent use of H2 antagonists or proton pump inhibitors (PPIs) may result in decreased effectiveness of posaconazole suspension. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Avoid the concurrent use of posaconazole suspension with H2 antagonists or proton pump inhibitors (PPIs).(1) If H2 antagonists or PPI therapy is required, use the tablet formulation or powder mix formulation of posaconazole. DISCUSSION: Concurrent cimetidine (400 mg twice daily) decreased both posaconazole (200 mg daily) maximum concentration (Cmax) and area-under-curve (AUC) levels by 39%.(1) No significant effects with other H2 blockers have been noted.(1) Esomeprazole (40 mg daily for 3 days) decreased the Cmax and AUC of a single dose of posaconazole suspension (400 mg) by 46% and 32%, respectively.(1) In a study of posaconazole levels in patients with acute myeloid leukemia or myelodysplastic syndrome, use of pantoprazole was associated with decreased posaconazole levels.(3) In a cross-over study in 5 healthy subjects, esomeprazole decreased the Cmax and AUC of posaconazole suspension by 37% and 84%, respectively. Simultaneous intake of Coca-Cola did not completely counteract the effects of esomeprazole.(4) In a study in healthy subjects, esomeprazole decreased the Cmax and AUC of posaconazole suspension by 55% and 49%, respectively. Simultaneous intake of Coca-Cola did not completely counteract the effects of esomeprazole.(5)	NOXAFIL, POSACONAZOLE
Methotrexate (Oncology-Injection )/Proton Pump Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Proton pump inhibitors may inhibit the active secretion of methotrexate from the kidney via inhibition of the hydrogen-potassium ATPase(1) and may reduce uptake of methotrexate into breast cancer resistance protein via competitive inhibition.(2,3) CLINICAL EFFECTS: The concurrent use of methotrexate and proton pump inhibitors may result in elevated levels of methotrexate and increased methotrexate-related adverse effects and toxicities, leading to increased risk of severe neurotoxicity, stomatitis, and myelosuppression, including neutropenia. PREDISPOSING FACTORS: Risk factors for methotrexate toxicity include: - High-dose oncology regimens - Impaired renal function, ascites, or pleural effusions PATIENT MANAGEMENT: For patients receiving high dose methotrexate with leucovorin rescue, consider discontinuation of proton pump inhibitors for the duration of therapy. Patients receiving concurrent use of methotrexate and proton pump inhibitors should be monitored closely for elevated methotrexate levels and methotrexate toxicity. The US manufacturer of omeprazole states that secretory ability returns gradually over three to five days following discontinuation.(4) Therefore, it would seem prudent to discontinue proton pump inhibitors several days prior to methotrexate therapy. DISCUSSION: In a clinical trial in 74 patients on high dose (1-5 G/m2) methotrexate therapy, data was examined to determine if proton pump inhibitor (omeprazole, pantoprazole, rabeprazole) use affects methotrexate elimination. Delayed elimination was found to be more frequent in those with co-administration of a proton pump inhibitor (31.7% vs. 13.8%), resulting in higher plasma methotrexate concentrations at 24, 48, and 74 hours. The effect was seen with lansoprazole, omeprazole, pantoprazole, and rabeprazole.(2) There are three case reports(1,5,6) of elevated methotrexate levels or delayed methotrexate elimination resulting from concurrent administration of high dose methotrexate and omeprazole, including one patient(6) that developed severe mucositis. In each case, omeprazole was discontinued and normal methotrexate kinetics were observed on subsequent cycles with no further adverse effects noted. In a case report of a 59 year-old male on low dose (15 mg weekly) methotrexate, administration of pantoprazole (20 mg daily) was found to increase the AUC of the metabolite 7-hydroxymethotrexate by 70%.(7) In a clinical trial, 28 adults with rheumatoid arthritis on low dose (7.5-15 mg weekly) methotrexate were assigned to receive lansoprazole (30 mg daily) and naproxen (500 mg twice daily) on Days 1-7 of therapy. The half life of the metabolite 7-hydroxymethotrexate was prolonged with concurrent administration, but no other statistically significant differences were found in regards to the plasma concentration profiles of methotrexate or 7-hydroxymethotrexate.(8)	METHOTREXATE, METHOTREXATE SODIUM
Lomitapide (Less Than or Equal To 30 mg)/Weak CYP3A4 Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Weak inhibitors of CYP3A4 may inhibit the metabolism of lomitapide.(1) Lomitapide is very susceptible to CYP3A4 inhibition. For example, in an interaction study with a strong CYP3A4 inhibitor (ketoconazole) lomitapide exposure was increased 27-fold.(2) Thus even weak CYP3A4 inhibitors may affect lomitapide exposure (AUC, area-under-curve). CLINICAL EFFECTS: Concurrent use of a weak inhibitor of CYP3A4 may result in 2-fold increases in lomitapide levels and toxicity from lomitapide.(1) PREDISPOSING FACTORS: This interaction may be more severe in patients with hepatic impairment or with end-stage renal disease.(1) PATIENT MANAGEMENT: The maximum lomitapide dose should be 30 mg daily for patients taking concomitant weak CYP3A4 inhibitors. Due to lomitapide's long half-life, it may take 1 to 2 weeks to see the full effect of this interaction. When initiating a weak CYP3A4 inhibitor in patients taking lomitapide 10 mg daily or more, decrease the dose of lomitapide by 50%. In patients taking lomitapide 5 mg daily, continue current dose. DISCUSSION: Lomitapide is very susceptible to CYP3A4 inhibition. For example, in an interaction study with a strong CYP3A4 inhibitor (ketoconazole) lomitapide exposure was increased 27-fold.(2) Based upon interactions with stronger inhibitors, weak inhibitors of CYP3A4 are predicted to increase lomitapide area-under-curve(AUC) 2-fold.(1) Weak CYP3A4 inhibitors linked to this interaction include alprazolam, amiodarone, amlodipine, asciminib, atorvastatin, azithromycin, Baikal skullcap, belumosudil, bicalutamide, blueberry juice, brodalumab, cannabidiol, capivasertib, cilostazol, cimetidine, ciprofloxacin, chlorzoxazone, clotrimazole, cranberry juice, cyclosporine, daridorexant, delavirdine, diosmin, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, larotrectinib, lacidipine, lapatinib, lazertinib, leflunomide, levamlodipine, linagliptin, lurasidone, maribavir, mavorixafor, olaparib, osilodrostat, palbociclib, pazopanib, peppermint oil, piperine, propiverine, propofol, ranitidine, ranolazine, remdesivir, resveratrol, roxithromycin, rucaparib, selpercatinib, sitaxsentan, skullcap, teriflunomide, ticagrelor, tolvaptan, trofinetide, viloxazine, vonoprazan, and zileuton.(1-3)	JUXTAPID
Ledipasvir; Velpatasvir/Proton Pump Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: The aqueous solubility of ledipasvir and velpatasvir is pH dependent. Higher gastric pH leads to lower solubility which may reduce ledipasvir and velpatasvir absorption.(1-3) CLINICAL EFFECTS: Coadministration of proton pump inhibitors (PPIs) may reduce the bioavailability of ledipasvir and velpatasvir, leading to decreased systemic levels and effectiveness.(1-3) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Omeprazole 20 mg daily, or comparable doses of other PPIs, may be administered simultaneously with ledipasvir-sofosbuvir under fasting conditions.(1) Coadministration of proton pump inhibitors is not recommended with sofosbuvir-velpatasvir. When concomitant proton pump inhibitor use is necessary in patients receiving sofosbuvir-velpatasvir, velpatasvir-sofosbuvir should be administered with food and taken 4 hours before omeprazole 20 mg. Use with other proton pump inhibitors has not been studied.(2) Omeprazole 20 mg daily may be administered with sofosbuvir-velpatasvir-voxilaprevir. Use with other proton pump inhibitors has not been studied.(3) When clinically appropriate, consider use of H2 blockers or antacids.(1-3) DISCUSSION: In an interaction study, omeprazole 20 mg given once daily simultaneously with ledipasvir-sofosbuvir, decreased ledipasvir exposure (AUC) by 4%. When omeprazole 20 mg once daily was given 2 hours prior to ledipasvir-sofosbuvir dose, ledipasvir exposure (AUC) decreased approximately 50%.(1) In an interaction study, omeprazole 20 mg given once daily simultaneously with sofosbuvir-velpatasvir decreased velpatasvir exposure (AUC) by 37%. When omeprazole 20 mg once daily was given 12 hours prior to sofosbuvir-velpatasvir dose, velpatasvir exposure (AUC) decreased 57%. When omeprazole 20 mg once daily was given 2 hours prior to sofosbuvir-velpatasvir dose, velpatasvir AUC decreased 48%. When omeprazole 20 mg once daily was given 4 hours after sofosbuvir-velpatasvir dose, velpatasvir AUC decreased 33%. When omeprazole 40 mg once daily was given 4 hours after sofosbuvir-velpatasvir dose, velpatasvir AUC decreased 56%.(2) In an interaction study, when omeprazole 20 mg once daily was given 2 hours prior to the sofosbuvir-velpatasvir-voxilaprevir dose, sofosbuvir AUC, velpatasvir AUC, and voxilaprevir AUC decreased 27%, 54%, and 20%, respectively. When omeprazole 20 mg once daily was given 4 hours after the sofosbuvir-velpatasvir-voxilaprevir dose, sofosbuvir AUC, velpatasvir AUC, and voxilaprevir AUC decreased 18%, 51%, and 5%, respectively %.(3) Proton pump inhibitors linked to this monograph are: dexlansoprazole, esomeprazole, lansoprazole, omeprazole, pantoprazole and rabeprazole.	EPCLUSA, HARVONI, LEDIPASVIR-SOFOSBUVIR, SOFOSBUVIR-VELPATASVIR, VOSEVI
Capecitabine/Proton Pump Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: The aqueous solubility of capecitabine is pH dependent. Higher gastric pH leads to lower solubility and altered tablet dissolution which may reduce capecitabine absorption.(1,2) CLINICAL EFFECTS: Coadministration of proton pump inhibitors (PPIs) may reduce the bioavailability of capecitabine, leading to decreased systemic levels and effectiveness.(1,2) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Coadministration of proton pump inhibitors with capecitabine may decrease bioavailability. When clinically appropriate, consider using H2 blockers or antacids. DISCUSSION: A retrospective study in early stage colorectal cancer patients treated with adjuvant monotherapy capecitabine examined recurrence-free survival (RFS) and overall survival (OS) in 1335 patients with and without concurrent proton pump inhibitor (PPI) therapy. The PPI group was defined as a prescription for a PPI filled at any point in time during capecitabine treatment. Patients in the capecitabine with concurrent PPI group had a statistically significant decrease in 5-year RFS (74% v 83%; hazard ratio (HR) 1.89; 95% confidence interval (CI) 1.07-3.35; p=0.03) compared to capecitabine without PPI therapy. OS was not significantly different between groups (81% PPI v 78% non-PPI; HR 1.13; 95% CI 0.6-2.14; p=0.7). After adjusting for male gender, stage III colorectal cancer, advance age >68, poorer ECOG PS, there was a trend toward decreased RFS in PPI patients (HR 1.65; 95% CI 0.93-2.94; p=0.09).(1) An ad hoc analysis of the TRIO-013/LOCiC trial examined coadministration of PPI therapy, defined as 20% or more overlap between a PPI prescription and trial treatment duration with capecitabine and/or lapatinib, on progression-free survival (PFS) and overall survival (OS). The secondary analysis examined 545 patients in which 42% were on concurrent PPI therapy. Patients in the non-PPI group had an improved median PFS (5.7 v 4.2 months; HR 1.55; 95% CI 1.29-1.81; p<0.001) and median OS (11.3 v 9.2 months; HR 1.34; 95% CI 1.06-1.62; p=0.04) compared with PPI users. A multivariate analysis reviewed effects of PPIs on both PFS and OS with capecitabine alone and found effects of PPI use on both PFS and OS was still significant (HR 1.68; p<0.001 and HR 1.41; p=0.001, respectively).(2) In a study in 12 subjects, concomitant administration of capecitabine with aluminum-magnesium hydroxide containing antacid 20 mL increased area-under-curve (AUC) and concentration maximum (Cmax) by 16% and 35%, respectively.(3) Proton pump inhibitors linked to this monograph include: dexlansoprazole, esomeprazole, lansoprazole, omeprazole, pantoprazole, rabeprazole.	CAPECITABINE, XELODA
Eliglustat/Weak CYP3A4 Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Weak inhibitors of CYP3A4 may inhibit the metabolism of eliglustat. If the patient is also taking an inhibitor of CYP2D6, eliglustat metabolism can be further inhibited.(1) CLINICAL EFFECTS: Concurrent use of an agent that is a weak inhibitor of CYP3A4 may result in elevated levels of and clinical effects of eliglustat, including prolongation of the PR, QTc, and/or QRS intervals, which may result in life-threatening cardiac arrhythmias.(1) PREDISPOSING FACTORS: If the patient is also taking an inhibitor of CYP2D6, is a poor metabolizer of CYP2D6, and/or has hepatic impairment, eliglustat metabolism can be further inhibited.(1) The risk of QT prolongation or torsades de pointes may be increased in patients with cardiovascular disease (e.g. heart failure, myocardial infarction, history of torsades de pointes, congenital long QT syndrome), hypokalemia, hypomagnesemia, hypocalcemia, bradycardia, female gender, or advanced age.(2) Concurrent use of more than one drug known to cause QT prolongation or higher systemic concentrations of either QT prolonging drug are additional risk factors for torsades de pointes. Factors which may increase systemic drug concentrations include rapid infusion of an intravenous dose or impaired metabolism or elimination of the drug (e.g. coadministration with an agent which inhibits its metabolism or elimination, genetic impairment in drug metabolism or elimination, and/or renal/hepatic dysfunction).(2) PATIENT MANAGEMENT: The concurrent use of eliglustat with weak inhibitors of CYP3A4 in poor metabolizers of CYP2D6 should be avoided.(1) The dosage of eliglustat with weak inhibitors of CYP3A4 in extensive metabolizers of CYP2D6 with mild (Child-Pugh Class A) hepatic impairment should be limited to 84 mg daily.(1) If concurrent therapy is warranted, consider obtaining serum calcium, magnesium, and potassium levels and monitoring ECG at baseline and at regular intervals. Correct any electrolyte abnormalities. Instruct patients to report any irregular heartbeat, dizziness, or fainting. DISCUSSION: Ketoconazole (400 mg daily), a strong inhibitor of CYP3A4, increased eliglustat (84 mg BID) maximum concentration (Cmax) and area-under-curve (AUC) by 4-fold and 4.4-fold, respectively, in extensive metabolizers. Physiologically-based pharmacokinetic (PKPB) models suggested ketoconazole would increase eliglustat Cmax and AUC by 4.4-fold and 5.4-fold, respectively, in intermediate metabolizers. PKPB models suggested ketoconazole may increase the Cmax and AUC of eliglustat (84 mg daily) by 4.3-fold and 6.2-fold, respectively, in poor metabolizers.(1) PKPB models suggested fluconazole, a moderate inhibitor of CYP3A4, would increase eliglustat Cmax and AUC by 2.8-fold and 3.2-fold, respectively, in extensive metabolizers and by 2.5-fold and 2.9-fold, respectively in intermediate metabolizers. PKPB models suggest that concurrent eliglustat (84 mg BID), paroxetine (a strong inhibitor of CYP2D6), and ketoconazole would increase eliglustat Cmax and AUC by 16.7-fold and 24.2-fold, respectively, in extensive metabolizers. In intermediate metabolizers, eliglustat Cmax and AUC would be expected to increase 7.5-fold and 9.8-fold, respectively.(1) PKPB models suggest that concurrent eliglustat (84 mg BID), terbinafine (a moderate inhibitor of CYP2D6), and ketoconazole would increase eliglustat Cmax and AUC by 10.2-fold and 13.6-fold, respectively, in extensive metabolizers. In intermediate metabolizers, eliglustat Cmax and AUC would be expected to increase 4.2-fold and 5-fold, respectively.(1) Weak inhibitors of CYP3A4 include: alprazolam, amlodipine, asciminib, azithromycin, Baikal skullcap, belumosudil, berberine, bicalutamide, blueberry, brodalumab, cannabidiol, chlorzoxazone, cilostazol, cimetidine, ciprofloxacin, clotrimazole, cranberry, cyclosporine, daclatasvir, daridorexant, delavirdine, dihydroberberine, diosmin, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lapatinib, larotrectinib, lazertinib, leflunomide, levamlodipine, linagliptin, lomitapide, lurasidone, olaparib, osilodrostat, palbociclib, pazopanib, peppermint oil, piperine, propiverine, propofol, ranolazine, remdesivir, resveratrol, roxithromycin, rucaparib, selpercatinib, simeprevir, sitaxsentan, skullcap, suvorexant, teriflunomide, ticagrelor, tolvaptan, trofinetide, and vonoprazan.(3,4)	CERDELGA
Secretin/H2 Antagonists; Proton Pump Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: H2 antagonists and proton pump inhibitors (PPIs) may result in an incorrect secretin stimulation test result.(1) CLINICAL EFFECTS: Concurrent use of H2 antagonists and proton pump inhibitors (PPIs) may impact the accuracy of the secretin stimulation test.(1) PREDISPOSING FACTORS: Patients with alcoholic or other liver disease may be hyperresponsive to stimulation with a secretin stimulation test, masking the presence of coexisting pancreatic disease. Consider additional testing and clinical assessment for diagnosis.(1) PATIENT MANAGEMENT: The US manufacturer of human secretin states concurrent use of H2 antagonists and proton pump inhibitors (PPIs) at the time of stimulation testing may cause the patient to be hyperresponsive to secretin stimulation and suggest false gastrinoma results. The manufacturer recommends discontinuing H2 antagonists at least 2 days prior to testing. The US manufacturer of vonoprazan recommends stopping vonoprazan at least 4 weeks prior to testing.(2-3) Consult prescribing information for PPIs before administering prior to a secretin stimulation test.(1) DISCUSSION: Concurrent use of H2 antagonists and proton pump inhibitors (PPIs) may impact the accuracy of the secretin stimulation test.(1)	CHIRHOSTIM
Selpercatinib/Proton Pump Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: The solubility of selpercatinib is pH dependent. Increase in gastric pH from proton pump inhibitors (PPIs) may decrease the solubility and absorption of selpercatinib.(1) CLINICAL EFFECTS: Use of proton pump inhibitors may result in decreased levels and effectiveness of selpercatinib.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Avoid the use of proton pump inhibitors (PPIs), H2 antagonists, and locally acting antacids in patients receiving treatment with selpercatinib. If coadministration with PPIs cannot be avoided, take selpercatinib with food.(1) If the PPI is replaced with a H2 antagonist, take selpercatinib 2 hours before or 10 hours after the H2 antagonist.(1) If the PPI is replaced with an antacid, take selpercatinib 2 hours before or 2 hours after the antacid.(1) DISCUSSION: In a study, omeprazole decreased the area-under-curve (AUC) and maximum concentration (Cmax) of selpercatinib (administered fasting) by 69% and 88%, respectively. When selpercatinib was administered with food, omeprazole did not significantly affect selpercatinib levels.(1)	RETEVMO
Selected Cephalosporins/Long Acting Antacids; H2s;PPIs SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Absorption of oral cefpodoxime or cefuroxime may be reduced in patients receiving concomitant treatment with acid reducing agents.(1-5) CLINICAL EFFECTS: Antibiotic efficacy against organisms with a high minimum inhibitory concentration (MIC) to cefpodoxime or cefuroxime could be decreased. PREDISPOSING FACTORS: Taking cefpodoxime or cefuroxime on an empty stomach magnifies this effect. PATIENT MANAGEMENT: If possible, avoid the use of H2 antagonists and proton pump inhibitors(PPIs) in patients taking cefpodoxime or cefuroxime. If concurrent therapy is needed with antacids, H2 antagonists, or PPIs, administer cefpodoxime or cefuroxime after eating to maximize oral absorption. Some vitamin preparations may contain sufficient quantities of calcium and/or magnesium salts with antacid properties to interact as well. DISCUSSION: In a study of ten subjects, administration of cefpodoxime after single dose famotidine 40 mg decreased both maximum concentration (Cmax) and area-under-curve (AUC) by approximately 40 percent compared with administration of cefpodoxime on an empty stomach.(3) In a study of 17 subjects, administration of cefpodoxime after single dose ranitidine 150 mg decreased Cmax and AUC by approximately 40 percent compared with administration of cefpodoxime on an empty stomach.(4) In a study performed prior to the introduction of PPIs, administration of ranitidine 300 mg and sodium bicarbonate followed by cefuroxime taken on a empty stomach lowered both Cmax and AUC of cefuroxime by approximately 40 per cent compared with administration of cefuroxime alone on an empty stomach. Postprandial administration of cefuroxime in subjects taking ranitidine was similar to that of subjects taking cefuroxime on an empty stomach.(5)	CEFPODOXIME PROXETIL, CEFUROXIME
Methylphenidate XR-ODT/H2 Antagonists;Proton Pump Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: The solubility of methylphenidate extended release orally disintegrating tablets (XR-ODT) is pH-dependent. At elevated pH, methylphenidate may be released from the tablets more quickly, resulting in increased absorption.(1) CLINICAL EFFECTS: Coadministration of H2 antagonists or proton pump inhibitors (PPIs) may result in an altered pharmacokinetic profile of methylphenidate XR-ODT, which may change the effectiveness and/or adverse effects of methylphenidate XR-ODT.(1,2) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Coadministration of methylphenidate XR-ODT with H2 antagonists or PPIs is not recommended.(1,2) DISCUSSION: In in vitro studies, when media pH was increased from 1.2 to 6.8, percentage release of methylphenidate from the XR-ODT tablet was increased by 67% at 0.5 hours, and by 93% at 2.5 hours. The increased dissolution of methylphenidate at higher pH may result in increased drug absorption and change the concentration-time profile of methylphenidate, which is correlated with pharmacological effect.(1)	COTEMPLA XR-ODT
Levoketoconazole/H2 Antagonists; Proton Pump Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: The aqueous solubility of levoketoconazole is pH dependent. Higher gastric pH leads to lower solubility. H2-receptor antagonists (H2RAs) and proton pump inhibitors (PPIs) increase gastric pH and may decrease the absorption of levoketoconazole.(1) CLINICAL EFFECTS: Coadministration of H2RAs or PPIs may reduce the bioavailability of levoketoconazole, leading to decreased systemic levels and effectiveness.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Coadministration of levoketoconazole with PPIs and H2RAs should be avoided.(1) DISCUSSION: Levoketoconazole is very slightly soluble in water but soluble below pH 2. H2RAs and PPIs raise gastric pH and may impair dissolution and absorption of levoketoconazole.(1)	RECORLEV
Vonoprazan/Strong or Moderate CYP3A4 Inducers SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Vonoprazan is a substrate of CYP3A4. Strong or moderate inducers of CYP3A4 may increase the metabolism of vonoprazan.(1) CLINICAL EFFECTS: The concurrent administration of strong or moderate CYP3A4 inducers may result in decreased levels and effectiveness of vonoprazan.(1) PREDISPOSING FACTORS: Induction effects may be more likely with regular use of the inducer for longer than 1-2 weeks. PATIENT MANAGEMENT: The manufacturer of vonoprazan states that concurrent use with strong or moderate CYP3A4 inducers should be avoided.(1) DISCUSSION: Strong CYP3A4 inducers like rifampin are predicted to decrease the area-under-curve (AUC) of vonoprazan by 80%, and moderate CYP3A4 inducers like efavirenz are predicted to decrease vonoprazan AUC by 50%.(1) Strong inducers of CYP3A4 include: apalutamide, barbiturates, carbamazepine, encorafenib, enzalutamide, fosphenytoin, ivosidenib, lumacaftor, mitotane, phenobarbital, phenytoin, primidone, rifampin, rifapentine, and St. John's wort. Moderate inducers of CYP3A4 include: belzutifan, bosentan, cenobamate, dabrafenib, dipyrone, efavirenz, elagolix, etravirine, lesinurad, lorlatinib, mavacamten, mitapivat, modafinil, nafcillin, pacritinib, repotrectinib, rifabutin, sotorasib, telotristat ethyl, thioridazine, and tovorafenib.(2-3)	ASA-BUTALB-CAFFEINE-CODEINE, ASCOMP WITH CODEINE, AUGTYRO, BOSENTAN, BRAFTOVI, BUTALB-ACETAMINOPH-CAFF-CODEIN, BUTALBITAL, BUTALBITAL-ACETAMINOPHEN, BUTALBITAL-ACETAMINOPHEN-CAFFE, BUTALBITAL-ASPIRIN-CAFFEINE, CAMZYOS, CARBAMAZEPINE, CARBAMAZEPINE ER, CARBATROL, CEREBYX, DILANTIN, DILANTIN-125, DONNATAL, DUZALLO, EFAVIRENZ, EFAVIRENZ-EMTRIC-TENOFOV DISOP, EFAVIRENZ-LAMIVU-TENOFOV DISOP, EPITOL, EQUETRO, ERLEADA, ETRAVIRINE, FIORICET, FIORICET WITH CODEINE, FOSPHENYTOIN SODIUM, INTELENCE, LORBRENA, LYSODREN, MITOTANE, MODAFINIL, MYSOLINE, NAFCILLIN, NAFCILLIN SODIUM, OJEMDA, ORIAHNN, ORILISSA, ORKAMBI, PENTOBARBITAL SODIUM, PHENOBARBITAL, PHENOBARBITAL SODIUM, PHENOBARBITAL-BELLADONNA, PHENOBARBITAL-HYOSC-ATROP-SCOP, PHENOHYTRO, PHENYTEK, PHENYTOIN, PHENYTOIN SODIUM, PHENYTOIN SODIUM EXTENDED, PRIFTIN, PRIMIDONE, PROVIGIL, PYRUKYND, RIFABUTIN, RIFADIN, RIFAMPIN, SEZABY, SYMFI, SYMFI LO, TAFINLAR, TALICIA, TEGRETOL, TEGRETOL XR, TENCON, THIORIDAZINE HCL, THIORIDAZINE HYDROCHLORIDE, TIBSOVO, TRACLEER, VONJO, WELIREG, XCOPRI, XERMELO, XTANDI
Atazanavir; Nelfinavir/Vonoprazan SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Proton pump inhibitors increase gastric pH. Vonoprazan is a gastric proton pump inhibitor. As gastric pH increases, the solubility of atazanavir and nelfinavir decreases.(1-4) CLINICAL EFFECTS: Concurrent use of atazanavir(2,3) or nelfinavir(4) and a proton pump inhibitor may result in decreased levels and effectiveness of atazanavir or nelfinavir. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The manufacturer of vonoprazan states concurrent use with atazanavir or nelfinavir should be avoided.(1) DISCUSSION: Vonoprazan decreases gastric acidity by suppressing gastric acid secretion and is characterized as a type of gastric proton-pump inhibitor.(1) In a pharmacodynamic study, a single 20 mg dose of vonoprazan, elevated the intragastric pH compared to placebo and was sustained for over 24-hours after dosing. The inhibitory effect of vonoprazan on acid secretion increased with repeated daily dosing and antisecretory effect reached steady state by Day 4 with a mean 24-hour intragastric pH of 6.0 following 20 mg once daily dose.(1) In a study of 16 subjects, atazanavir (400 mg daily) area-under-curve (AUC), maximum concentration (Cmax) and minimum concentration (Cmin) decreased 94%, 96% and 95% respectively, when given with omeprazole (40 mg daily). Omeprazole AUC and Cmax increased 145% and 124% respectively.(2) In a study of 15 subjects, atazanavir AUC, Cmax and Cmin decreased 76%, 72% and 78% respectively, when given with omeprazole (40 mg daily) and ritonavir (100 mg daily).(2) In a study in 13 subjects, administration of omeprazole (20 mg daily) 12 hours before atazanavir/ritonavir (300/100 mg daily) decreased atazanavir Cmax, AUC, and Cmin by 39%, 42%, and 46%, respectively; however, the atazanavir AUC and Cmin were 10% and 2.4-fold higher than average levels seen with atazanavir 400 mg alone.(2) In a study in 14 subjects, administration of omeprazole (20 mg daily) 1 hour before atazanavir/ritonavir (400/100 mg daily) decreased atazanavir Cmax, AUC, and Cmin by 31%, 30%, and 31%, respectively; however, the atazanavir AUC and Cmin were 32% and 3.3-fold higher than average levels seen with atazanavir 400 mg alone.(2)	ATAZANAVIR SULFATE, EVOTAZ, REYATAZ, VIRACEPT
Pexidartinib/Vonoprazan SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Multiple mechanisms are involved in this interaction. With concurrent use of pexidartinib and vonoprazan: 1. The solubility of pexidartinib is pH dependent. Changes in gastric pH from proton pump inhibitors (PPIs) may decrease the absorption of pexidartinib.(1) Vonoprazan is a PPI.(2) 2. Pexidartinib is a moderate CYP3A4 inducer. If pexidartinib is absorbed, it may increase the CYP3A4-mediated metabolism of vonoprazan.(1,2) The triple pak formulation of vonoprazan-clarithromycin-amoxicillin is also affected by the mechanisms above when used with pexidartinib. In addition, if pexidartinib is absorbed, CYP3A4 induction by pexidartinib may increase the metabolism of clarithromycin, and clarithromycin, a strong CYP3A4 inhibitor, may decrease the metabolism of pexidartinib.(1,2) CLINICAL EFFECTS: Use of proton pump inhibitors may result in decreased levels and effectiveness of pexidartinib.(1) If pexidartinib is absorbed, it may decrease the levels and effectiveness of vonoprazan and clarithromycin. In addition, concurrent use of a strong CYP3A4 inhibitor may increase the levels and toxicities of pexidartinib, such as hepatotoxicity.(1,2) Symptoms can include nausea, vomiting, jaundice, dark urine, abdominal pain, and unexplained fatigue. The net effect of vonoprazan-clarithromycin on pexidartinib levels is unknown. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Avoid the use of vonoprazan, vonoprazan-amoxicillin and vonoprazan-clarithromycin-amoxicillin in patients receiving treatment with pexidartinib.(1,2) Consider the use of short-acting antacids. If antacids are used, separate the administration times by at least 2 hours for pexidartinib.(1) If H2 antagonist therapy is required, pexidartinib must be given 10 hours after the H2 blocker and at least 2 hours before the next dose of the H2 blocker.(1) DISCUSSION: Coadministration of esomeprazole decreased pexidartinib maximum concentration (Cmax) and area-under-the-curve (AUC) by 55% and 50%.(1) Vonoprazan and clarithromycin are CYP3A4 substrates. Strong CYP3A4 inducers like rifampin are predicted to decrease the AUC of vonoprazan by 80%, and moderate CYP3A4 inducers like efavirenz are predicted to decrease vonoprazan AUC by 50%.(1) Pexidartinib is a moderate CYP3A4 inducer.(2-3) Coadministration of itraconazole (strong CYP3A4 inhibitor) increased pexidartinib Cmax and AUC by 48% and 70%.(1)	TURALIO
Sotorasib/Vonoprazan SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: The aqueous solubility of sotorasib is pH dependent. Higher gastric pH leads to lower solubility which may reduce sotorasib absorption. Vonoprazan is a proton pump inhibitor (PPI).(1) If sotorasib is absorbed, it may increase the CYP3A4 metabolism of vonoprazan and clarithromycin.(2) CLINICAL EFFECTS: Coadministration of proton pump inhibitors (PPIs) or H2 antagonists may reduce the bioavailability of sotorasib, leading to decreased systemic levels and effectiveness.(1) Also, the concurrent administration of strong or moderate CYP3A4 inducers, such as sotorasib, may result in decreased levels and effectiveness of vonoprazan and clarithromycin.(2) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Coadministration of sotorasib with proton pump inhibitors, H2 antagonists, and antacids should be avoided. If coadministration with an acid-reducing agent is unavoidable, take sotorasib 4 hours before or 10 hours after a locally acting antacid.(1) The UK manufacturer of sotorasib states if co-administration with an acid-reducing agent (such as a PPI or an H2 antagonist) is required, sotorasib should be taken with an acidic beverage (such as cola). Alternatively, sotorasib should be taken 4 hours before or 10 hours after administration of a local antacid.(3) The manufacturer of vonoprazan states that concurrent use with strong or moderate CYP3A4 inducers should be avoided.(2) DISCUSSION: The solubility of sotorasib in the aqueous media decreases over the range pH 1.2 to 6.8 from 1.3 mg/mL to 0.03 mg/mL. In an interaction study, coadministration of repeat doses of omeprazole with a single dose of sotorasib decreased sotorasib maximum concentration (Cmax) by 65% and area-under-curve (AUC) by 57% under fed conditions, and decreased sotorasib Cmax by 57% and AUC by 42% under fasted conditions. Under fasted conditions, co-administration of repeat doses of omeprazole with a single dose of sotorasib and 240ml of an acidic beverage (non-diet cola) decreased sotorasib Cmax by 32% and AUC by 23%. The UK manufacturer of sotorasib states the clinical relevance of the decreased sotorasib exposure when co-administered with omeprazole and cola is unclear and sotorasib efficacy might be reduced.(3) Coadministration of a single dose of famotidine given 10 hours prior to and 2 hours after a single dose of sotorasib under fed conditions decreased sotorasib Cmax by 35% and AUC by 38%.(1) Vonoprazan and clarithromycin are CYP3A4 substrates. Strong CYP3A4 inducers like rifampin are predicted to decrease the AUC of vonoprazan by 80%, and moderate CYP3A4 inducers like efavirenz are predicted to decrease vonoprazan AUC by 50%.(2)	LUMAKRAS
Selected Kinase Inhibitors/Vonoprazan SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: The solubility of bosutinib,(1) dacomitinib,(2) dasatinib,(3) erlotinib,(4) gefitinib,(5) neratinib,(6) nilotinib,(7) and pazopanib(8) is pH dependent. Changes in gastric pH from vonoprazan(9) may decrease the absorption of bosutinib,(1) dacomitinib,(2) dasatinib,(3) erlotinib,(4) gefitinib,(5) neratinib,(6) nilotinib,(7) and pazopanib.(8) CLINICAL EFFECTS: Use of vonoprazan may result in decreased levels and effectiveness of bosutinib,(1) dacomitinib,(2) dasatinib,(3) erlotinib,(4) gefitinib,(5) neratinib,(6) nilotinib,(7) and pazopanib.(8) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Avoid the use of vonoprazan(9) in patients receiving treatment with bosutinib,(1) dacomitinib,(2) dasatinib,(3) erlotinib,(4) gefitinib,(5) neratinib,(6) nilotinib,(7) and pazopanib.(8) Consider the use of short-acting antacids in these patients.(1-8) If antacids are used, separate the administration times by several hours(1-8) but at least 2 hours for bosutinib,(1) dasatinib,(3) and nilotinib,(7) 6 hours for gefitinib,(5) and 3 hours for neratinib.(6) If H2 antagonist therapy is required with dacomitinib, dacomitinib must be given once daily 10 hours after the H2 blocker and 6 hours before the next dose of the H2 blocker.(2) If H2 antagonist therapy is required with gefitinib, administer gefitinib 6 hours before or after H2-antagonists or antacids.(5) If H2 antagonist therapy is required with erlotinib, neratinib, or nilotinib, the kinase inhibitor must be given 10 hours after the H2 blocker and at least 2 hours before the next dose of the H2 blocker.(4,6,7) The manufacturer of Phyrago states that it can be administered with gastric acid reducing agents. Administration times should be separated with antacids.(14) DISCUSSION: Vonoprazan decreases gastric acidity by suppressing gastric acid secretion and is characterized as a type of gastric proton-pump inhibitor.(9) In a pharmacodynamic study, a single 20 mg dose of vonoprazan, elevated the intragastric pH compared to placebo and was sustained for over 24-hours after dosing. The inhibitory effect of vonoprazan on acid secretion increased with repeated daily dosing and antisecretory effect reached steady state by Day 4 with a mean 24-hour intragastric pH of 6.0 following 20 mg once daily dose.(9) In a study, concurrent rabeprazole decreased the Cmax and AUC of dacomitinib by 51% and 39%, respectively.(2) In a study in 24 healthy subjects, administration of a single dose of dasatinib (50 mg) 10 hours after famotidine decreased dasatinib area-under-curve (AUC) and maximum concentration (Cmax) by 61% and 63%, respectively.(3) In a study in 14 healthy subjects, administration of a single dose of dasatinib (100 mg) 22 hours after omeprazole (40 mg at steady state) decreased dasatinib AUC and Cmax by 43% and 42%, respectively.(3) In a study in 24 healthy subjects, simultaneous administration of dasatinib (50 mg) with aluminum hydroxide/magnesium hydroxide (30 ml) decreased dasatinib AUC and Cmax by 55% and 58%, respectively. In the same subjects, administration of the antacid 2 hours before dasatinib decreased dasatinib Cmax by 26%, but had no effect on dasatinib AUC.(3) In a study, concurrent omeprazole decreased the AUC and Cmax of erlotinib by 46% and 61%, respectively.(4) In a study, administration of erlotinib two hours after a dose of ranitidine (300 mg), erlotinib AUC and Cmax decreased by 33% and 54%, respectively. Administration of erlotinib 10 hours after and two hours before ranitidine (150 mg twice daily), erlotinib AUC and Cmax decreased by 15% and 17%, respectively.(4) In a case report, a patient that was given erlotinib (150 mg daily,) with algeldrate/magnesium hydroxide (800/400 mg four times daily 4 hours before or 2 hours after erlotinib) did not see a significant reduction in serum trough concentrations of erlotinib. When the patient was switched to intravenous pantoprazole via continuous infusion (8 mg per hour), serum erlotinib levels decreased significantly below minimal trough concentrations for effective tyrosine kinase inhibition. When the patient was switched to oral pantoprazole (40 mg twice daily), serum trough levels of erlotinib returned to therapeutic levels.(10) In a study in healthy subjects, high dose ranitidine with sodium carbonate was administered to maintain gastric pH above 5.0 and gefitinib AUC decreased 47%.(5) In a study in 15 healthy subjects, lansoprazole (30 mg at steady state) decreased the Cmax and AUC of a single dose of neratinib (240 mg) by 71% and 65%, respectively.(6) In a study in 22 healthy subjects, pretreatment with esomeprazole (40 mg daily), decreased the Cmax and AUC of a single dose of nilotinib (400 mg) by 27% and 34%, respectively.(7,11) Increasing the dosage of nilotinib or separating the administration time of nilotinib and the proton pump inhibitor is not expected to eliminate the interaction.(7) There were no significant changes in nilotinib pharmacokinetics when famotidine was administered 10 hours before or 2 hours after nilotinib.(7) There were no significant changes in nilotinib pharmacokinetics when an antacid (aluminum hydroxide/magnesium hydroxide/simethicone) was administered 2 hours before or after nilotinib.(7) In a study in 13 patients, esomeprazole (40 mg daily for 5 days) decreased the Cmax and AUC of pazopanib (400 mg daily) by 42% and 40%, respectively, when compared to the administration of pazopanib alone.(12) In an open-label, crossover study in 17 evaluable patients, omeprazole (40 mg daily) had no significant effects on the pharmacokinetics, pharmacodynamics, or safety of bortezomib (1.3 mg/m2).(13) Phyrago is not sensitive to increased gastric pH due to its polymer formulation. No clinically significant pharmacokinetic changes were seen with concurrent administration of Phyrago with omeprazole (proton pump inhibitor) or famotidine (H2 receptor antagonist).(14)	BOSULIF, DANZITEN, DASATINIB, ERLOTINIB HCL, GEFITINIB, IRESSA, NERLYNX, NILOTINIB HCL, PAZOPANIB HCL, SPRYCEL, TARCEVA, TASIGNA, VIZIMPRO, VOTRIENT
Pemetrexed/Proton Pump Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Proton pump inhibitors may inhibit the active secretion of pemetrexed from the kidney via the organic anion transporter 3 (OAT3).(1,2,3) CLINICAL EFFECTS: The concurrent use of pemetrexed and proton pump inhibitors may result in increased levels and toxicities of pemetrexed, including severe neurotoxicity, stomatitis, and myelosuppression, including neutropenia. PREDISPOSING FACTORS: Risk factors for pemetrexed toxicity include high-dose oncology regimens, impaired renal function, and concurrent use of nephrotoxic medications. PATIENT MANAGEMENT: For patients receiving pemetrexed, consider discontinuation of proton pump inhibitors for the duration of pemetrexed therapy. If concurrent use cannot be avoided, monitor closely for elevated pemetrexed levels and toxicity. DISCUSSION: A prospective observational study of 156 patients receiving pemetrexed-based therapy found that severe hematological toxicity, namely neutropenia and anemia, occurred in 34/55 patients (61.8%) taking concurrent proton pump inhibitors (PPIs) and in 36/101 patients (35.6%) who did not consume PPIs. In Cox regression multivariable analysis, the hazard ratio for severe hematological toxicity with PPI use was 2.51 (95% CI = 1.47-4.26). Esomeprazole, pantoprazole, and lansoprazole were the most consumed PPIs in the study, but no correlation was investigated.(1) A retrospective review of 61 patients investigated medication-related causes of severe hematological toxicity in patients on pemetrexed/carboplatin chemotherapy. Twenty-three patients took PPIs: lansoprazole (n=16), esomeprazole (n=5), omeprazole (n=1), and rabeprazole (n=1). In a multiple logistic regression analysis, use of PPIs in patients receiving pemetrexed/carboplatin combination chemotherapy was associated severe hematotoxicity (odds ratio: 5.34, 95% CI: 1.06-26.94, P = 0.042).(2) In an in vitro analysis and retrospective study, lansoprazole, rabeprazole, pantoprazole, esomeprazole, omeprazole, and vonoprazan were shown to inhibit OAT3-mediated uptake of pemetrexed, with lansoprazole having the greatest inhibitory effect. In the multivariate analysis of 108 patients, concurrent use of lansoprazole (but not other PPIs) and pemetrexed/carboplatin was a significant risk factor for the development of hematological toxicity (odds ratio: 10.004, P = 0.005).(3) In a retrospective study of 74 patients who received pemetrexed, 24 patients (32%) were on concomitant PPIs. Pemetrexed toxicity was associated with cystatin clearance (p=0.0135), albumin level (p=0.0333), and proton pump inhibitors (p=0.035) on multivariate analysis. Most patients (n=14) took esomeprazole or omeprazole, with the remainder taking lansoprazole (n=5), pantoprazole (n=4) or an unspecified agent.(4)	ALIMTA, AXTLE, PEMETREXED, PEMETREXED DISODIUM, PEMFEXY, PEMRYDI RTU
Sparsentan/H2 Antagonists; Proton Pump Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: The aqueous solubility of sparsentan is pH dependent. Higher gastric pH leads to lower solubility. H2-receptor antagonists (H2RAs) and proton pump inhibitors (PPIs) increase gastric pH and may decrease the absorption of sparsentan.(1) CLINICAL EFFECTS: Coadministration of H2RAs or PPIs may reduce the bioavailability of sparsentan, leading to decreased systemic levels and effectiveness.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Coadministration of sparsentan with PPIs and H2RAs should be avoided.(1) DISCUSSION: Sparsentan is practically insoluble in water but has intrinsic solubility of 1.48 mg/mL and 0.055 mg/mL below pH 1.2 and 6.8, respectively. H2RAs and PPIs raise gastric pH and may impair dissolution and absorption of sparsentan.(1)	FILSPARI
Clopidogrel/Vonoprazan SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Clopidogrel is a prodrug and is converted to its active metabolite via a 2 step process. The first conversion step is mediated by CYP2C19, CYP1A2 and CYP2B6, while the second step is mediated by CYP3A4, CYP2B6 and CYP2C19.(1,2) CYP2C19 contributes to both steps and is thought to be the more important enzyme involved in formation of the pharmacologically active metabolite.(1) Vonoprazan may inhibit CYP2C19 mediated conversion to the active metabolite of clopidogrel.(7-10) CLINICAL EFFECTS: Concurrent use of vonoprazan may result in decreased clopidogrel effectiveness, resulting in increased risk of adverse cardiac events. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The US manufacturer of vonoprazan states concurrent use should be carefully monitored. Monitor patients closely for clopidogrel efficacy and consider alternative antiplatelet agents.(7,8) Evaluate patient risk for gastrointestinal (GI) bleeding. When PPIs are needed, use dexlansoprazole, lansoprazole, pantoprazole or rabeprazole as they have a lower interaction risk.(1,11) Consider the use of H2 blockers (such as famotidine, nizatidine, or ranitidine) in patients with a low bleeding risk and reserve the use of PPIs for patients at higher risk of GI bleeding. The US manufacturer of clopidogrel states that alternatives to clopidogrel should be considered in patients who are poor metabolizers of CYP2C19.(1) It would be prudent to assume that patients taking strong inhibitors of CYP2C19 are poor metabolizers of this isoenzyme. Moderate CYP2C19 inhibitors, such as omeprazole, and weak CYP2C19 inhibitors, such as cimetidine, may also affect this interaction. Consider alternatives to vonoprazan in patients stabilized on clopidogrel and alternatives to clopidogrel in patients stabilized on vonoprazan. If concurrent therapy is warranted, consider appropriate testing to assure adequate inhibition of platelet reactivity. DISCUSSION: In a study in 7 healthy subjects, concurrent use of vonoprazan resulted in an increase and decrease in the area under the plasma concentration-time curve (AUC) of proguanil and cycloguanil, respectively. The AUC ratio of cycloguanil/proguanil was reduced to 0.507-fold (95% CI 0.409-0.605) with concurrent vonoprazan.(9) In a study in 12 healthy subjects, the inhibition of platelet aggregation was decreased with daily and every other day use of vonoprazan with clopidogrel (21.8% and 25%, respectively) compared to clopidogrel alone (40.8%).(10)	CLOPIDOGREL, CLOPIDOGREL BISULFATE, PLAVIX
Nirogacestat/H2 Antagonists; Proton Pump Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: The aqueous solubility of nirogacestat is pH dependent. Higher gastric pH leads to lower solubility which may reduce nirogacestat absorption.(1) CLINICAL EFFECTS: Coadministration of proton pump inhibitors (PPIs) or H2 antagonists may reduce the bioavailability of nirogacestat, leading to decreased systemic levels and effectiveness.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Coadministration of nirogacestat with proton pump inhibitors, H2 antagonists, and antacids should be avoided. If coadministration with an acid-reducing agent is unavoidable, take nirogacestat 2 hours before or 2 hours after a locally acting antacid.(1) DISCUSSION: The solubility of nirogacestat is poor at a pH >= 6.(1) Concomitant use of proton pump inhibitors, H2 antagonists, or antacids are expected to reduce concentrations of nirogacestat.(1)	OGSIVEO

There are 10 moderate interactions. The clinician should assess the patient’s characteristics and take action as needed. Actions required for moderate interactions include, but are not limited to, discontinuing one or both agents, adjusting dosage, altering administration.

Drug Interaction	Drug Names
Itraconazole; Ketoconazole/Agents Affecting Gastric pH SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Antacids, buffers in didanosine products, H2 antagonists, and proton-pump inhibitors increase the stomach pH. Quinapril tablets may contain a high percentage of magnesium. Since some orally administered azole antifungal agents require an acidic medium for optimal absorption, agents may decrease the absorption of azole antifungal agents. CLINICAL EFFECTS: Simultaneous administration of an antacid, buffered didanosine, a H2 antagonist, or a proton-pump inhibitor may result in decreased therapeutic effects of the azole antifungal. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: If the concurrent administration of these two agents cannot be avoided, consider administering two capsules of glutamic acid hydrochloride 15 minutes before administering the antifungal and separate the administration times of the antifungal and the agent affecting gastric pH by at least two hours. DISCUSSION: Itraconazole, ketoconazole, and posaconazole require an acidic medium for predictable dissolution and absorption decreases as pH increases and proton pump inhibitors are expected to decrease their absorption.(1-4) In a study in 11 healthy subjects, omeprazole (40 mg daily) decreased the maximum concentration (Cmax) and area-under-curve (AUC) of itraconazole (200 mg single dose) by 66% and 64%, respectively.(5) In a study in 15 healthy subjects, omeprazole (40 mg daily) had no effect on the pharmacokinetics of itraconazole solution.(6) In a study in 9 healthy subjects, omeprazole (60 mg) decreased the AUC of ketoconazole (200 mg single dose) by 83.4% compared to control (ketoconazole alone). Administration of Coca-Cola (240 ml) with ketoconazole and omeprazole raised ketoconazole AUC to 65% of control values.(7) Omeprazole has been shown to have no significant effect on the absorption of fluconazole(8) or voriconazole.(9) Case reports and in-vivo studies have documented significant decreases in ketoconazole levels during concurrent therapy with H-2 antagonists, including cimetidine and ranitidine. Concurrent administration of itraconazole and famotidine resulted in a significant decrease in itraconazole levels, but no significant changes in famotidine levels. An interaction should be expected to occur between both ketoconazole or itraconazole and the other H-2 antagonists.(10-14) In randomized, open-labeled, cross-over study in 12 healthy subjects, simultaneous administration of an antacid decreased the area-under-curve (AUC) and maximum concentration (Cmax) of a single dose of itraconazole (200 mg) by 66% and 70%, respectively. Time to Cmax (Tmax) increased by 70%.(15) This interaction has also been reported in a case report.(16) In a study in 3 subjects, simultaneous administration of a combination aluminum hydroxide/magnesium hydroxide (30 ml) decreased the AUC of a single dose of ketoconazole (200 mg) by 41%.(172) In a case report, a patient receiving concurrent ketoconazole with aluminum hydroxide, cimetidine, and sodium bicarbonate did not respond to therapy until cimetidine was discontinued and the administration time of aluminum hydroxide and cimetidine was changed to 2 hours after ketoconazole. In a follow-up study in 2 subjects, concurrent cimetidine and sodium hydroxide lowered ketoconazole levels.(18) In a study in 14 subjects, simultaneous administration of aluminum hydroxide/magnesium hydroxide (20 ml, 1800 mg/1200 mg) had no significant effects on fluconazole pharmacokinetics.(3) In a randomized, open-label, cross-over study in 6 subjects, simultaneous administration of itraconazole with buffered didanosine tablets resulted in undetectable levels of itraconazole.(19) In a randomized cross-over study in 12 HIV-positive subjects, administration of buffered didanosine tablets 2 hours after ketoconazole had no effects on ketoconazole levels.(20) In a randomized, cross-over, open-label study in 24 healthy subjects, simultaneous administration of enteric-coated didanosine had no effect on ketoconazole pharmacokinetics.(21) One or more of the drug pairs linked to this monograph have been included in a list of interactions that could be considered for classification as "non-interruptive" in EHR systems. This DDI subset was vetted by an expert panel commissioned by the U.S. Office of the National Coordinator (ONC) for Health Information Technology.	ITRACONAZOLE, ITRACONAZOLE MICRONIZED, KETOCONAZOLE, SPORANOX, TOLSURA
Amphetamines/H2 Antagonists; Proton Pump Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: H2 antagonists and proton pump inhibitors (PPIs) may alter the timing of absorption of amphetamines. CLINICAL EFFECTS: Concurrent use of amphetamines and H2 antagonists or PPIs may result in an increased absorption rate and a change in timing of peak amphetamine levels. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The US manufacturer states that patients receiving concurrent amphetamines and H2 antagonists or PPIs should be monitored for changes in the timing and clinical effects of amphetamines.(1) Monitor patients receiving concurrent therapy for changes in amphetamine effectiveness and side effects. The Canadian manufacturer states that concurrent use of proton pump inhibitors and amphetamines should be avoided.(3) DISCUSSION: During concurrent use of a proton pump inhibitor, the median time to maximum concentration (Tmax) of Adderall XR decreased from 5 hours to 2.75 hours.(3) In a 4-way crossover study in healthy subjects, omeprazole had no effect on the total exposure a single dose of mixed amphetamine salts (20 mg); however median Tmax decreased from 5 hours to 2.75 hours. Approximately 50% of subjects had a decrease in Tmax of equal to or greater than 1 hour.(4)	ADDERALL, ADDERALL XR, ADZENYS XR-ODT, AMPHETAMINE SULFATE, DESOXYN, DEXEDRINE, DEXTROAMPHETAMINE SULFATE, DEXTROAMPHETAMINE SULFATE ER, DEXTROAMPHETAMINE-AMPHET ER, DEXTROAMPHETAMINE-AMPHETAMINE, DYANAVEL XR, EVEKEO, METHAMPHETAMINE HCL, MYDAYIS, PROCENTRA, ZENZEDI
Methotrexate(low strength inj, oral)/Proton Pump Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Proton pump inhibitors(PPIs) may inhibit the active secretion of methotrexate from the kidney via inhibition of the hydrogen-potassium ATPase(1) and may reduce uptake of methotrexate into breast cancer resistance protein via competitive inhibition.(2,3) CLINICAL EFFECTS: The concurrent use of methotrexate and proton pump inhibitors may result in elevated levels of methotrexate and increased methotrexate-related adverse effects and toxicities, leading to increased risk of severe neurotoxicity, stomatitis, and myelosuppression, including neutropenia.(1-7,9) PREDISPOSING FACTORS: High dose methotrexate therapy appears to increase the risk for and severity of this interaction.(4,9) PATIENT MANAGEMENT: Patients receiving concurrent use of methotrexate and proton pump inhibitors should be monitored closely for elevated methotrexate levels and methotrexate toxicity. The US manufacturer of omeprazole states that secretory ability returns gradually over three to five days following discontinuation.(4) This interaction has best described in patients receiving high dose methotrexate for cancer treatment. Therefore, it would seem prudent to discontinue proton pump inhibitors several days prior to high dose methotrexate therapy. The magnitude and frequency of this interaction in patients receiving less than or equal to 15 mg weekly is less clear. While a small study suggested lansoprazole was safe in rheumatoid arthritis patients taking 7.5 - 15 mg weekly(8), at least one case report of PPI associated methotrexate toxicity at a low dose (15 mg IM weekly) has been described.(7) DISCUSSION: In a clinical trial in 74 patients on high dose (1-5 G/m2) methotrexate therapy, data was examined to determine if proton pump inhibitor (omeprazole, pantoprazole, rabeprazole) use affects methotrexate elimination. Delayed elimination was found to be more frequent in those with co-administration of a proton pump inhibitor (31.7% vs. 13.8%), resulting in higher plasma methotrexate concentrations at 24, 48, and 74 hours. The effect was seen with lansoprazole, omeprazole, pantoprazole, and rabeprazole.(2) There are three case reports(1,5,6) of elevated methotrexate levels or delayed methotrexate elimination resulting from concurrent administration of high dose methotrexate and omeprazole, including one patient(6) that developed severe mucositis. In each case, omeprazole was discontinued and normal methotrexate kinetics were observed on subsequent cycles with no further adverse effects noted. In a case report of a 59 year-old male on low dose (15 mg weekly) methotrexate, administration of pantoprazole (20 mg daily) was found to increase the AUC of the metabolite 7-hydroxymethotrexate by 70%.(7) In a manufacturer sponsored clinical trial, 28 adults with rheumatoid arthritis on low dose (7.5-15 mg weekly) methotrexate were assigned to receive lansoprazole (30 mg daily) and naproxen (500 mg twice daily) on Days 1-7 of therapy. The half life of the metabolite 7-hydroxymethotrexate was prolonged with concurrent administration, but no other statistically significant differences were found in regards to the plasma concentration profiles of methotrexate or 7-hydroxymethotrexate.(8)	JYLAMVO, METHOTREXATE, OTREXUP, RASUVO, TREXALL, XATMEP
Mycophenolate Mofetil/Proton Pump Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: The exact mechanism is unknown. One theory is that proton pump inhibitors may prevent mycophenolate mofetil from being converted to mycophenolic acid in the gastrointestinal tract.(1-5) CLINICAL EFFECTS: Concurrent use of proton pump inhibitors (PPIs) may result in decreased mycophenolic acid levels and effects, including increased risk of transplant rejection. PREDISPOSING FACTORS: Other factors which may affect systemic mycophenolate exposure include renal function, serum albumin, gender, race, the choice of calcineurin inhibitor (CNI), and use of other drugs which inhibit absorption or enterohepatic recirculation of mycophenolate. PATIENT MANAGEMENT: If concurrent treatment of mycophenolate mofetil and a PPI is needed, evaluate predisposing risk factors (e.g. renal function, gender, race, and presence of other interacting drugs) which may increase or decrease mycophenolate exposure. If a patient is at risk for low mycophenolic acid levels, options may include converting to delayed release mycophenolic acid (mycophenolate sodium) which is not susceptible to this interaction (4,8,9), or monitoring mycophenolic acid levels to assure therapeutic concentrations are attained. DISCUSSION: A study compared 21 heart transplant patients maintained on mycophenolate mofetil and pantoprazole (40 mg daily) to 12 patients maintained on mycophenolate without pantoprazole. There was no significant difference in mycophenolate dose between the groups. However, mycophenolic acid levels at 30 minutes, 1 hour, 2 hours, and 12 hours were significantly lower in patients who received pantoprazole (63%, 44%, 34%, 52%, respectively). Mycophenolic acid area-under-curve (AUC) and maximum concentration (Cmax) were also significantly lower in patients who received pantoprazole (30% and 78%, respectively). There was a trend for more acute rejection episodes and transplant vasculopathy in patients receiving pantoprazole.(1) A study compared 23 patients with autoimmune diseases maintained on mycophenolate mofetil and pantoprazole (40 mg daily) to 13 patients maintained on mycophenolate without pantoprazole. There was no significant difference in mycophenolate dose between the groups. The AUC and Cmax of mycophenolic acid decreased by 37% and 60%, respectively, in patients treated with pantoprazole. The activity of mycophenolic acid decreased by 42% in patients receiving pantoprazole.(2) In a study in 22 heart transplant patients receiving mycophenolate mofetil (1000 mg twice daily), mycophenolic acid levels at 30 and 60 minutes post-dose were 55% and 37% lower, respectively, when patients were receiving pantoprazole (40 mg daily). The AUC and Cmax of mycophenolic acid were both 41% when patients were receiving pantoprazole. The time to reach Cmax (Tmax) was 29% longer.(3) A study in 12 healthy subjects compared the effects of pantoprazole (40 mg twice daily) on single doses of mycophenolate mofetil (1000 mg) and enteric-coated mycophenolate sodium (720 mg). Pantoprazole decreased the Cmax and AUC of mycophenolic acid following mycophenolate mofetil administration by 57% and 27%, respectively. There were no effects on mycophenolate acid following mycophenolate sodium administration.(4) A study in renal transplant patients, patients receiving mycophenolate mofetil and tacrolimus without PPI therapy (n=22) were compared to patients receiving concurrent mycophenolate mofetil, tacrolimus, and lansoprazole (30 mg, n=22) and patients receiving concurrent mycophenolate mofetil, tacrolimus, and rabeprazole (10 mg, n=17). Mycophenolic acid Cmax, dose-adjusted Cmax, and AUC(0-6h) were significantly lower in patients receiving lansoprazole when compared to patients not receiving PPI therapy. There were no significant differences between patients receiving rabeprazole and those not receiving PPI therapy; however, rabeprazole acid lowering effects are lower than lansoprazole.(5) A cross-sectional, retrospective analysis of renal transplant patients on omeprazole, mycophenolate, and a calcineurin inhibitor found that in the first week post-transplant the mycophenolate active moiety levels were reduced to a point of clinical significance. However, after that first week, the effect seemed to be less clinically significant.(6) In a study of heart transplant patients, use of pantoprazole (20 mg to 80 mg daily) significantly reduced the AUC of mycophenolic acid produced from a mean daily dose of 2.2+/-0.8 mycophenolate mofetil (p=0.02). However, mycophenolic acid minimum concentration (Cmin) was not significantly different.(7) In a study in healthy subjects, the Cmax and AUC of mycophenolic acid were decreased when mycophenolate mofetil was administered with omeprazole (20 mg BID); however, there was no effect on the Cmax or AUC of mycophenolic acid when enteric-coated mycophenolate mofetil was administered with omeprazole.(8) In a study in heart or lung transplant patients, concurrent pantoprazole had no effect on the Cmax, Tmax, or AUC of mycophenolic acid following administration of enteric-coated mycophenolate sodium. Additionally no significant difference of inosine 5?-monophosphate dehydrogenase (IMPDH) activity was seen with EC-mycophenolate given alone or with pantoprazole.(9) In a subanalysis of the CLEAR Study, there were no significant effects of omeprazole or pantoprazole on mycophenolic acid levels in the study group randomized to received intensified dosing with mycophenolate mofetil (1.5 g BID for 5 days, then 1 g BID).(10)	CELLCEPT, MYCOPHENOLATE MOFETIL, MYHIBBIN
Tacrolimus/Moderate and Weak CYP3A4 Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Moderate and weak inhibitors of CYP3A4 may inhibit the metabolism of tacrolimus.(1) CLINICAL EFFECTS: Concurrent use of a CYP3A4 inhibitor may result in elevated levels of and toxicity from tacrolimus, including nephrotoxicity, neurotoxicity, and prolongation of the QTc interval and life-threatening cardiac arrhythmias, including torsades de pointes.(1) PREDISPOSING FACTORS: The risk of QT prolongation or torsade de pointes may be increased in patients with cardiovascular disease (e.g. heart failure, myocardial infarction, history of torsade de pointes, congenital long QT syndrome), hypokalemia, hypomagnesemia, hypocalcemia, bradycardia, female gender, or advanced age.(2) Concurrent use of more than one drug known to cause QT prolongation or higher systemic concentrations of either QT prolonging drug are additional risk factors for torsade de pointes. Factors which may increase systemic drug concentrations include rapid infusion of an intravenous dose or impaired metabolism or elimination of the drug (e.g. coadministration with an agent which inhibits its metabolism or elimination, and/or renal/hepatic dysfunction).(2) PATIENT MANAGEMENT: The US manufacturer of tacrolimus recommends monitoring tacrolimus whole blood trough concentrations and reducing tacrolimus dose if needed.(1) Consider obtaining serum calcium, magnesium, and potassium levels and monitoring ECG at baseline and at regular intervals. Correct any electrolyte abnormalities. Instruct patients to report any irregular heartbeat, dizziness, or fainting. DISCUSSION: In a study of 26 renal transplant recipients, conjugated estrogens 3.75 mg daily increased the tacrolimus dose-corrected concentration of tacrolimus by 85.6%. Discontinuation of the conjugated estrogens led to a decrease in tacrolimus concentration of 46.6%.(3) A case report describes a 65-year-old kidney transplant recipient who was stable on tacrolimus 9 mg per day with trough levels of 5 to 7.5 ng/mL. Ten days after starting on estradiol gel 0.5 mg per day, her tacrolimus level rose to 18.3 ng/mL and serum creatinine (Scr) rose from 1.1 mg/dL at baseline to 2 mg/dL. Tacrolimus dose was reduced by 60%, and trough levels and Scr normalized after two weeks.(4) A study of 16 healthy volunteers found that elbasvir 50 mg/grazoprevir 200 mg daily increased the area-under-curve (AUC) of tacrolimus by 43%, while the maximum concentration (Cmax) of tacrolimus was decreased by 40%.(5) An analysis of FAERS data from 2004-2017, found a significant assoc ation between transplant rejection and concurrent use of tacrolimus and clotrimazole (reporting odds ration 1.92, 95% CI). A retrospective study of 7 heart transplant patients on concurrent tacrolimus and clotrimazole troche showed a significant correlation between tacrolimus trough concentration and AUC after clotrimazole discontinuation. Tacrolimus clearance and bioavailability after clotrimazole discontinuation was 2.2-fold greater (0.27 vs. 0.59 L/h/kg) and the trough concentration decreased from 6.5 ng/mL at 1 day to 5.3 ng/mL at 2 days after clotrimazole discontinuation.(7) A retrospective study of 26 heart transplant patients found that discontinuation of concurrent clotrimazole with tacrolimus in the CYP3A5 expresser group had a 3.3-fold increase in apparent oral clearance and AUC of tacrolimus (0.27 vs. 0.89 L/h/kg) compared to the CYP3A5 non expresser group with a 2.2-fold mean increase (0.18 vs. 0.39 L/h/kg).(8) A study of 6 adult kidney transplant recipients found that clotrimazole (5-day course) increased the tacrolimus AUC 250% and the blood trough concentrations doubled (27.7 ng/ml versus 27.4 ng/ml). Tacrolimus clearance decreased 60% with coadministration of clotrimazole.(9) A case report describes a 23-year-old kidney transplant recipient who was stable on tacrolimus 5 mg twice daily, mycophenolate mofetil 30 mg daily, prednisone (30 mg daily tapered over time to 5 mg), and clotrimazole troche 10 mg four times daily. Discontinuation of clotrimazole resulted in a decrease in tacrolimus trough levels from 13.7 ng/ml to 5.4 ng/ml over a period of 6 days. Clotrimazole was restarted with tacrolimus 6 mg resulting in an increased tacrolimus level of 19.2 ng/ml.(10) A retrospective study in 95 heart transplant recipients on concurrent clotrimazole and tacrolimus found a median tacrolimus dose increase of 66.7% was required after clotrimazole discontinuation. Tacrolimus trough concentration was found to have decreased 42.5% after clotrimazole discontinuation.(11) A retrospective study in 65 pancreas transplant patients on concurrent tacrolimus, clotrimazole, cyclosporine, and prednisone found that clotrimazole discontinuation at 3 months after transplantation may cause significant tacrolimus trough level reductions.(12) Moderate CYP3A4 inhibitors linked to this monograph include: aprepitant, berotralstat, clofazimine, conivaptan, fluvoxamine, lenacapavir, letermovir, netupitant, nirogacestat, and tofisopam.(6) Weak CYP3A4 inhibitors linked to this monograph include: alprazolam, avacopan, baikal skullcap, berberine, bicalutamide, blueberry, brodalumab, chlorzoxazone, cimetidine, cranberry juice, daclatasvir, daridorexant, delavirdine, diosmin, estrogens, flibanserin, fosaprepitant, fostamatinib, ginkgo biloba, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lazertinib, linagliptin, lomitapide, lumateperone, lurasidone, peppermint oil, piperine, propiverine, ranitidine, remdesivir, resveratrol, rimegepant, simeprevir, sitaxsentan, skullcap, suvorexant, ticagrelor, tolvaptan, trofinetide, viloxazine, and vonoprazan-amoxicillin.(6)	ASTAGRAF XL, ENVARSUS XR, PROGRAF, TACROLIMUS, TACROLIMUS XL
Lemborexant (Less Than or Equal To 5 mg)/Weak CYP3A4 Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Inhibitors of CYP3A4 may inhibit the metabolism of lemborexant.(1) CLINICAL EFFECTS: Concurrent use of an inhibitor of CYP3A4 may result in increased levels of and effects from lemborexant, including somnolence, fatigue, CNS depressant effects, daytime impairment, headache, and nightmare or abnormal dreams.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The maximum recommended dose of lemborexant with concurrent use of a weak CYP3A4 inhibitors should not exceed 5 mg per dose.(1) DISCUSSION: Lemborexant is a CYP3A4 substrate. In a PKPB model, concurrent use of lemborexant with itraconazole increased area-under-curve (AUC) and concentration maximum (Cmax) by 3.75-fold and 1.5-fold, respectively. Concurrent use of lemborexant with fluconazole increased AUC and Cmax by 4.25-fold and 1.75-fold, respectively.(1) Weak inhibitors of CYP3A4 include: alprazolam, amiodarone, amlodipine, asciminib, azithromycin, Baikal skullcap, belumosudil, berberine, bicalutamide, blueberry, brodalumab, cannabidiol, capivasertib, chlorzoxazone, cilostazol, cimetidine, ciprofloxacin, clotrimazole, cranberry, cyclosporine, daclatasvir, daridorexant, delavirdine, dihydroberberine, diosmin, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lapatinib, larotrectinib, lazertinib, leflunomide, levamlodipine, linagliptin, lomitapide, lurasidone, mavorixafor, olaparib, osilodrostat, palbociclib, pazopanib, peppermint oil, piperine, propiverine, propofol, ranitidine, ranolazine, remdesivir, resveratrol, roxithromycin, rucaparib, selpercatinib, simeprevir, sitaxsentan, skullcap, suvorexant, teriflunomide, ticagrelor, tolvaptan, trofinetide, viloxazine, and vonoprazan.(1,2)	DAYVIGO
Ubrogepant/Weak CYP3A4 Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Weak inhibitors of CYP3A4 may inhibit the metabolism of ubrogepant.(1) CLINICAL EFFECTS: Concurrent use of ubrogepant with weak CYP3A4 inhibitors may result in an increase in exposure of ubrogepant.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The manufacturer recommends a dosage adjustment of ubrogepant when used concomitantly with weak CYP3A4 inhibitors. Initial dose of ubrogepant should not exceed 50 mg when used concomitantly with weak inhibitors of CYP3A4. A second dose may be given within 24 hours but should not exceed 50 mg when used concurrently with weak CYP3A4 inhibitors.(1) DISCUSSION: Coadministration of ubrogepant with verapamil, a moderate CYP3A4 inhibitor, resulted in a 3.5-fold and 2.8-fold increase in area-under-curve (AUC) and concentration maximum (Cmax), respectively. No dedicated drug interaction study was conducted to assess concomitant use with weak CYP3A4 inhibitors. The conservative prediction of the maximal potential increase in ubrogepant exposure with weak CYP3A4 inhibitors is not expected to be more than 2-fold.(1) Weak inhibitors of CYP3A4 include: alprazolam, amiodarone, amlodipine, asciminib, azithromycin, Baikal skullcap, berberine, bicalutamide, blueberry, brodalumab, cannabidiol, capivasertib, chlorzoxazone, cilostazol, cimetidine, ciprofloxacin, clotrimazole, cranberry, cyclosporine, daclatasvir, delavirdine, dihydroberberine, diosmin, elagolix, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lapatinib, larotrectinib, lazertinib, leflunomide, levamlodipine, linagliptin, lomitapide, lurasidone, maribavir, mavorixafor, osilodrostat, palbociclib, pazopanib, peppermint oil, piperine, propiverine, propofol, ranitidine, ranolazine, remdesivir, resveratrol, roxithromycin, simeprevir, sitaxsentan, skullcap, suvorexant, teriflunomide, ticagrelor, tolvaptan, trofinetide, viloxazine, and vonoprazan.(2,3)	UBRELVY
Belumosudil/Proton Pump Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Belumosudil is best absorbed in an acidic environment. Proton pump inhibitors (PPIs) decrease gastric acidity and may decrease belumosudil absorption and systemic concentrations.(1) CLINICAL EFFECTS: Coadministration of PPIs with belumosudil decreases systemic concentrations of belumosudil, which may decrease the efficacy of belumosudil.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Increase the dosage of belumosudil to 200 mg twice daily when coadministered with PPIs.(1) DISCUSSION: Coadministration of rabeprazole decreased belumosudil maximum concentration (Cmax) by 87% and area-under-curve (AUC) by 80%, and omeprazole decreased belumosudil Cmax by 68% and AUC by 47% in healthy subjects.(1)	REZUROCK
Sirolimus Protein-Bound/Slt Moderate and Weak CYP3A4 Inhibit SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Moderate and weak CYP3A4 inhibitors may inhibit the metabolism of sirolimus by CYP3A4.(1) CLINICAL EFFECTS: Concurrent use of moderate or weak CYP3A4 inhibitors may result in elevated levels of and side effects from sirolimus.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The US manufacturer of sirolimus protein-bound injection (Fyarro) states a dose reduction to 56 mg/m2 is recommended when used concurrently with moderate or weak CYP3A4 inhibitors. Concurrent use with strong CYP3A4 inhibitors should be avoided.(1) DISCUSSION: In an open, randomized, cross-over trial in 18 healthy subjects, concurrent single doses of diltiazem (120 mg) and sirolimus (10 mg) increased sirolimus area-under-curve (AUC) and maximum concentration (Cmax) by 60% and by 43%, respectively. Sirolimus apparent oral clearance and volume of distribution decreased by 38% and 45%, respectively. There were no effects on diltiazem pharmacokinetics or pharmacodynamics.(2) In a study in 26 healthy subjects, concurrent sirolimus (2 mg daily) with verapamil (180 mg twice daily) increased sirolimus AUC and Cmax by 2.2-fold and 2.3-fold, respectively. The AUC and Cmax of the active S-enantiomer of verapamil each increased by 1.5-fold. Verapamil time to Cmax (Tmax) was increased by 1.2 hours.(2) Moderate and weak CYP3A4 inhibitors linked to this monograph include: alprazolam, amlodipine, aprepitant, avacopan, azithromycin, berberine, berotralstat, bicalutamide, blueberry, brodalumab, chlorzoxazone, cilostazol, cimetidine, ciprofloxacin, clofazimine, conivaptan, daclatasvir, daridorexant, delavirdine, diosmin, entrectinib, erythromycin, estrogen, flibanserin, fluvoxamine, fosaprepitant, fosnetupitant, fostamatinib, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lazertinib, lenacapavir, levamlodipine, linagliptin, lomitapide, lumateperone, lurasidone, mavorixafor, netupitant, omeprazole, osilodrostat, peppermint oil, piperine, propiverine, propofol, ranitidine, ranolazine, remdesivir, resveratrol, rimegepant, roxithromycin, scutellarin, simeprevir, sitaxsentan, suvorexant, ticagrelor, tofisopam, tolvaptan, trofinetide and vonoprazan.(3,4)	FYARRO
Palbociclib/Proton Pump Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: The mechanism of this interaction is not fully understood and may involve dysbiosis or gastric pH changes resulting from proton pump inhibitors (PPIs).(1,2) The aqueous solubility of palbociclib is pH-dependent. Higher gastric pH leads to lower solubility which may reduce palbociclib absorption.(1) CLINICAL EFFECTS: Coadministration of PPIs may reduce the bioavailability of palbociclib, leading to decreased systemic levels and effectiveness.(1) Although administration of palbociclib with food minimizes the decrease in absorption,(1) retrospective studies and a meta-analysis have found lower survival rates among patients on concurrent PPIs.(2-7) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The manufacturer of palbociclib capsules states that palbociclib should be taken with food, whereas palbociclib tablets may be taken with or without food. There are no constraints on concurrent use of proton pump inhibitors.(1) Given the decreased survival rates observed in patients who received PPIs with palbociclib, the authors of some studies on concurrent use of these agents have made various recommendations, including avoiding PPIs with palbociclib, using ribociclib instead of palbociclib, using low strengths of PPIs, or using H2-antagonists or antacids.(2-7) DISCUSSION: Palbociclib solubility decreases significantly above pH 4.(1) In a study with healthy volunteers, rabeprazole decreased the maximum concentration (Cmax) and area-under-curve (AUC) of single-dose palbociclib without food by 80% and 62%, respectively. In another study of healthy volunteers in a fed state, rabeprazole decreased Cmax and AUC of single-dose palbociclib by 41% and 13%, respectively.(1) A systematic review and meta-analysis examined studies of HER2-negative, hormone receptor-positive patients with metastatic breast cancer treated with palbociclib or ribociclib with or without concomitant PPIs that reported on survival outcomes. Eight studies consisting of 2,584 patients (830 on PPIs, 1754 not on PPIs) were included. Patients on concurrent PPIs had a significantly higher risk of all-cause mortality (HR, 2.03; 95% CI, 1.49 to 2.77) and disease progression (HR, 1.75; 95% CI, 1.26 to 2.43) compared to patients not on PPIs, though there was a high degree of heterogeneity in disease progression.(2) A retrospective cohort of patients with advanced or metastatic breast cancer treated with palbociclib capsules (344 patients on PPIs, 966 patients not on PPIs) revealed that patients on PPIs had shorter progression-free survival (PFS) (HR 1.76 (95% CI, 1.46-2.13) and lower overall survival (HR, 2.71 [95% CI, 2.07-3.53]).(3) A post-hoc analysis of the phase 2 PARSIFAL trial evaluated PFS in patients on palbociclib capsules. 326 patients were PPI-naive, 64 patients were early users of PPIs (started on PPIs since starting palbociclib), and 91 patients were long-term users of PPIs. PPI use was associated with a shorter PFS (HR in early PPI users 1.5; 95% CI 1.1-2.2; HR in long-term PPI users 1.4; 95% CI 1.1-1.9).(4) A retrospective study of 50 patients with metastatic breast cancer on palbociclib found that concurrent PPI use was associated with a shorter PFS.(5) In an observational study of patients with metastatic breast cancer on palbociclib capsules, PFS was compared between 65 patients on PPIs and 40 patients not on PPIs. On multivariate analysis, PPI usage was an independent predictor of shorter PFS (HR 5.60; 95% confidence interval: 1.98-15.85).(6) A retrospective observational cohort of metastatic breast cancer patients on palbociclib found that patients on concurrent PPIs had a shorter PFS than those not on PPIs (14.0 versus 37.9 months, p < 0.0001).(7) In contrast to these findings, other studies have not found a detrimental effect of PPIs on palbociclib efficacy. A retrospective observational study focused on 112 patients with endocrine-resistant metastatic breast cancer on palbociclib capsules (n=58) and tablets (n=20). There was no difference in PFS in patients on concurrent PPIs compared to those not on PPIs.(8) A study looking at 82 patients with metastatic breast cancer treat 1st line with palbociclib tablets(9) and a retrospective observational study on metastatic breast cancer patients on palbociclib capsules(10) also did not find a significantly different PFS between patients with and without concurrent PPIs.	IBRANCE

The following contraindication information is available for VOQUEZNA (vonoprazan fumarate):

Overview
Contraindicated
Severe
Moderate

Drug contraindication overview.

* Known hypersensitivity to vonoprazan or any component of the formulation. *Concomitant use with rilpivirine-containing products.

There are 1 contraindications. Absolute contraindication.

Contraindication List
Lactation

There are 5 severe contraindications. Adequate patient monitoring is recommended for safer drug use.

Severe List
Child-pugh class B hepatic impairment
Child-pugh class C hepatic impairment
Chronic kidney disease stage 4 (severe) GFR 15-29 ml/min
Chronic kidney disease stage 5 (failure) GFr<15 ml/min
Disease of liver

There are 4 moderate contraindications. Clinically significant contraindication, where the condition can be managed or treated before the drug may be given safely.

Moderate List
Hypomagnesemia
Kidney disease with likely reduction in glomerular filtration rate (GFr)
Osteoporosis
Vitamin b12 deficiency

The following adverse reaction information is available for VOQUEZNA (vonoprazan fumarate):

Overview
Severe
Less Severe

Adverse reaction overview.

The most common adverse reactions (>=2%) associated with vonoprazan when used for healing of erosive esophagitis include gastritis, diarrhea, abdominal distension, abdominal pain, and nausea. The most common adverse reactions (>=3%) associated with vonoprazan when used for maintenance of healed erosive esophagitis include gastritis, abdominal pain, dyspepsia, hypertension, and urinary tract infection. The most common adverse reactions (>=2%) associated with vonoprazan when used for the treatment of H. pylori infection include diarrhea, dysgeusia, vulvovaginal candidiasis, abdominal pain, headache, hypertension, and nasopharyngitis.

There are 9 severe adverse reactions.

More Frequent	Less Frequent
None.	None.

Rare/Very Rare
Anaphylaxis Erythema multiforme Hepatic failure Hepatocellular damage Interstitial nephritis Jaundice Stevens-johnson syndrome Toxic epidermal necrolysis Urticaria

There are 40 less severe adverse reactions.

More Frequent	Less Frequent
Abdominal distension Acute abdominal pain Diarrhea Dysgeusia Dyspepsia Gastritis Headache disorder Hypertension Nausea Pharyngitis Urinary tract infection Vulvovaginal candidiasis	None.

Rare/Very Rare
Abnormal hepatic function tests Acute eruptions of skin Anemia Benign fundic gland polyposis of stomach Clostridioides difficile infection Depression Diabetes mellitus Dizziness Eczema Eructation Flatulence Fracture General weakness Hypocalcemia Hypokalemia Hypomagnesemia Insomnia Lymphocytosis Peripheral edema Skin rash Syncope Tachycardia Thrombocytopenic disorder Upper respiratory infection Vertigo Vitamin b12 deficiency Vomiting Xerostomia

Rare/Very Rare

Abnormal hepatic function tests
Acute eruptions of skin
Anemia
Benign fundic gland polyposis of stomach
Clostridioides difficile infection
Depression
Diabetes mellitus
Dizziness
Eczema
Eructation
Flatulence
Fracture
General weakness
Hypocalcemia
Hypokalemia
Hypomagnesemia
Insomnia
Lymphocytosis
Peripheral edema
Skin rash
Syncope
Tachycardia
Thrombocytopenic disorder
Upper respiratory infection
Vertigo
Vitamin b12 deficiency
Vomiting
Xerostomia

The following precautions are available for VOQUEZNA (vonoprazan fumarate):

Pediatric
Pregnant
Lactation
Geriatric

Safety and effectiveness of vonoprazan in pediatric patients have not been established.

Contraindicated

None

Severe Precaution

None

Management or Monitoring Precaution

None

There are no adequate and well-controlled studies of vonoprazan in pregnant women to evaluate for drug-associated risks of major birth defects, miscarriage, or other adverse maternal or fetal outcomes. Report pregnancies to the Phathom Pharmaceuticals Adverse Event reporting line at 1-888-775-PHAT (7428).

There are no data regarding the presence of vonoprazan in human milk, the effects on the breastfed infant, or the effects on milk production. Vonoprazan and its metabolites are present in rat milk. Liver injury occurred in the offspring of pregnant and lactating rats administered oral vonoprazan at exposures approximately equal to and greater than the maximum recommended human dose.

When a drug is present in animal milk, it is likely that the drug will be present in human milk. Because of the potential risk of adverse liver effects shown in animal studies with vonoprazan, advise patients not to breastfeed during treatment with the drug.

There were 200 patients 65 years of age and older in the clinical trial of vonoprazan for erosive esophagitis and relief of heartburn; among patients who received vonoprazan, 18% were 65 years of age or older and 2% were 75 years of age or older. There were 218 patients 65 years of age and older in the clinical trial for the treatment of H. pylori infection; among patients who received vonoprazan, 22% were 65 years of age or older and 3% were 75 years of age or older.

No overall differences in safety or effectiveness were observed between these patients and younger adult patients, and other reported clinical experience has not identified differences in responses between geriatric and younger adult patients, but greater sensitivity of some older individuals cannot be ruled out. No clinically meaningful differences in the pharmacokinetics of vonoprazan are expected in patients 65 years of age and older compared to younger adult patients.

The following icd codes are available for VOQUEZNA (vonoprazan fumarate)'s list of indications:

Erosive esophagitis
K21.0	Gastro-esophageal reflux disease with esophagitis
K21.00	Gastro-esophageal reflux disease with esophagitis, without bleeding
K21.01	Gastro-esophageal reflux disease with esophagitis, with bleeding
K22.1	Ulcer of esophagus
K22.10	Ulcer of esophagus without bleeding
K22.11	Ulcer of esophagus with bleeding
Gastroesophageal reflux disease
K21	Gastro-esophageal reflux disease
K21.0	Gastro-esophageal reflux disease with esophagitis
K21.00	Gastro-esophageal reflux disease with esophagitis, without bleeding
K21.9	Gastro-esophageal reflux disease without esophagitis
H. pylori gastrointestinal tract infection
B96.81	Helicobacter pylori [h. pylori] as the cause of diseases classified elsewhere