Sofosbuvir, velpatasvir, and voxilaprevir

7 DRUG INTERACTIONS P-gp inducers and/or moderate to strong CYP inducers (e.g., St. John's wort, carbamazepine): May decrease concentrations of sofosbuvir, velpatasvir, and/or voxilaprevir. Use of VOSEVI with P-gp inducers and/or moderate to strong CYP inducers is not recommended. ( 5.4 , 7 ) Consult the full prescribing information prior to use for potential drug interactions. ( 4 , 5.3 , 5.4 , 7 ) Clearance of HCV infection with direct acting antivirals may lead to changes in hepatic function, which may impact safe and effective use of concomitant medications.

Frequent monitoring of relevant laboratory parameters (INR or blood glucose) and dose adjustments of certain concomitant medications may be necessary. ( 7.3 )

7.1 Potential for Other Drugs to Affect VOSEVI Sofosbuvir, velpatasvir, and voxilaprevir are substrates of drug transporters P-gp and BCRP while GS-331007 (predominant circulating metabolite of sofosbuvir) is not. Voxilaprevir is also a substrate of OATP1B1 and OATP1B3. In vitro, slow metabolic turnover of velpatasvir by CYP2B6, CYP2C8, and CYP3A4 and of voxilaprevir by CYP1A2, CYP2C8, and primarily CYP3A4 was observed. Drugs that are inducers of P-gp and/or moderate to strong inducers of CYP2B6, CYP2C8, or CYP3A4 (e.g., St.

John's wort, carbamazepine) may significantly decrease plasma concentrations of sofosbuvir, velpatasvir, and/or voxilaprevir leading to reduced therapeutic effect of VOSEVI. The use of these agents with VOSEVI is not recommended [see Warnings and Precautions (5.4) and Clinical Pharmacology (12.3) ]. VOSEVI may be coadministered with P-gp, BCRP, and CYP inhibitors. The use of OATP inhibitors which may substantially increase exposure of voxilaprevir (e.g., cyclosporine) with VOSEVI is not recommended [see Clinical Pharmacology (12.3) ].

7.2 Potential for VOSEVI to Affect Other Drugs Velpatasvir and voxilaprevir are inhibitors of drug transporters P-gp, BCRP, OATP1B1, and OATP1B3. Velpatasvir is also an inhibitor of OATP2B1. Coadministration of VOSEVI with drugs that are substrates of these transporters may alter the exposure of such drugs. Coadministration of VOSEVI with BCRP substrates (e.g., methotrexate, mitoxantrone, imatinib, irinotecan, lapatinib, rosuvastatin, sulfasalazine, topotecan) is not recommended [see Clinical Pharmacology (12.3) ].

7.3 Established and Potentially Significant Drug Interactions Clearance of HCV infection with direct acting antivirals may lead to changes in hepatic function, which may impact the safe and effective use of concomitant medications. For example, altered blood glucose control resulting in serious symptomatic hypoglycemia has been reported in diabetic patients in postmarketing case reports and published epidemiological studies. Management of hypoglycemia in these cases required either discontinuation or dose modification of concomitant medications used for diabetes treatment.

Frequent monitoring of relevant laboratory parameters (e.g., International Normalized Ratio [INR] in patients taking warfarin, blood glucose levels in diabetic patients) or drug concentrations of concomitant medications such as cytochrome P450 substrates with a narrow therapeutic index (e.g., certain immunosuppressants) is recommended to ensure safe and effective use. Dose adjustments of concomitant medications may be necessary. Table 3 provides a listing of established or potentially clinically significant drug interactions.

The drug interactions described are based on studies conducted with either VOSEVI, the components of VOSEVI (sofosbuvir, velpatasvir, and/or voxilaprevir), or are predicted drug interactions that may occur with VOSEVI [see Contraindications (4) , Warnings and Precautions (5.3 , 5.4) , and Clinical Pharmacology (12.3) ]. Table 3 Potentially Significant Drug Interactions: Alteration in Dose or Regimen May Be Recommended Based on Drug Interaction Studies or Predicted Interaction This table is not all inclusive. Concomitant Drug Class: Drug Name Effect on Concentration ↓ = decrease, ↑ = increase.

Clinical Effect/Recommendation Acid Reducing Agents: ↓ velpatasvir Velpatasvir solubility decreases as pH increases. Drugs that increase gastric pH are expected to decrease concentration of velpatasvir. Antacids (e.g., aluminum and magnesium hydroxide) Separate antacid and VOSEVI administration by 4 hours. H 2 -receptor antagonists (e.g., famotidine) These interactions have been studied in healthy adults. H 2 -receptor antagonists may be administered simultaneously with or staggered from VOSEVI at a dose that does not exceed doses comparable with famotidine 40 mg twice daily. Proton-pump inhibitors (e.g., omeprazole) Omeprazole 20 mg can be administered with VOSEVI.

Use with other proton pump-inhibitors has not been studied. Antiarrhythmics: amiodarone Effect on amiodarone, sofosbuvir, velpatasvir, and voxilaprevir concentrations unknown Coadministration of amiodarone with VOSEVI may result in serious symptomatic bradycardia. The mechanism of this effect is unknown. Coadministration of amiodarone with VOSEVI is not recommended; if coadministration is required, cardiac monitoring is recommended [see Warnings and Precautions (5.3) ]. digoxin ↑ digoxin Therapeutic concentration monitoring of digoxin is recommended when coadministered with VOSEVI.

Refer to digoxin prescribing information for monitoring and dose modification recommendations for concentration increases with unclear magnitude. Anticoagulants: dabigatran etexilate ↑ dabigatran Clinical monitoring of dabigatran is recommended when coadministered with VOSEVI. Refer to dabigatran etexilate prescribing information for dose modification recommendations in the setting of moderate renal impairment. Anticonvulsants: carbamazepine phenytoin phenobarbital ↓ sofosbuvir ↓ velpatasvir ↓ voxilaprevir Coadministration is not recommended.

Antimycobacterials: rifampin ↓ sofosbuvir ↓ velpatasvir ↑ voxilaprevir (single dose) ↓ voxilaprevir (multiple dose) Coadministration with rifampin is contraindicated [see Contraindications (4) ]. rifabutin rifapentine ↓ sofosbuvir ↓ velpatasvir ↓ voxilaprevir Coadministration is not recommended. Antiretrovirals: atazanavir lopinavir ↑ voxilaprevir Coadministration of VOSEVI with atazanavir- or lopinavir-containing regimens is not recommended. tipranavir/ritonavir ↓ sofosbuvir ↓ velpatasvir Coadministration is not recommended. The effect on voxilaprevir is unknown. efavirenz ↓ velpatasvir ↓ voxilaprevir Coadministration of VOSEVI with efavirenz-containing regimens is not recommended.

tenofovir disoproxil fumarate (tenofovir DF) ↑ tenofovir Monitor for tenofovir-associated adverse reactions in patients receiving VOSEVI concomitantly with a regimen containing tenofovir DF. Refer to the prescribing information of the tenofovir DF-containing product for recommendations on renal monitoring. Herbal Supplements: St. John's wort ↓ sofosbuvir ↓ velpatasvir ↓ voxilaprevir Coadministration is not recommended. HMG-CoA Reductase Inhibitors: pravastatin ↑ pravastatin Coadministration of VOSEVI with pravastatin has been shown to increase the concentration of pravastatin, which is associated with increased risk of myopathy, including rhabdomyolysis.

Pravastatin may be administered with VOSEVI at a dose that does not exceed pravastatin 40 mg. rosuvastatin ↑ rosuvastatin Coadministration of VOSEVI with rosuvastatin may significantly increase the concentration of rosuvastatin which is associated with increased risk of myopathy, including rhabdomyolysis. Coadministration of VOSEVI with rosuvastatin is not recommended. pitavastatin ↑ pitavastatin Coadministration with VOSEVI may increase the concentration of pitavastatin and is not recommended, due to an increased risk of myopathy, including rhabdomyolysis.

atorvastatin fluvastatin lovastatin simvastatin ↑ atorvastatin ↑ fluvastatin ↑ lovastatin ↑ simvastatin Coadministration with VOSEVI may increase the concentrations of atorvastatin, fluvastatin, lovastatin, and simvastatin. Increased statin concentrations may increase the risk of myopathy, including rhabdomyolysis. Use the lowest approved statin dose. If higher doses are needed, use the lowest necessary statin dose based on a risk/benefit assessment. Immunosuppressants: cyclosporine ↑ voxilaprevir Coadministration of voxilaprevir with cyclosporine has been shown to substantially increase the plasma concentration of voxilaprevir, the safety of which has not been established.

Coadministration of VOSEVI with cyclosporine is not recommended.

7.4 Drugs without Clinically Significant Interactions with VOSEVI Based on drug interaction studies conducted with the components of VOSEVI (sofosbuvir, velpatasvir, and/or voxilaprevir) or VOSEVI, no clinically significant drug interactions have been observed with the following drugs [see Clinical Pharmacology (12.3) ]: VOSEVI: cobicistat, darunavir, elvitegravir, emtricitabine, ethinyl estradiol/norgestimate, gemfibrozil, rilpivirine, ritonavir, tenofovir alafenamide,…

8.1 Pregnancy Risk Summary No adequate human data are available to establish whether or not VOSEVI poses a risk to pregnancy outcomes. In animal reproduction studies, no evidence of adverse developmental outcomes was observed with the components of VOSEVI (sofosbuvir, velpatasvir, or voxilaprevir) at exposures greater than those in humans at the recommended human dose (RHD) [see Data ] .

During organogenesis in the mouse, rat, and rabbit, systemic exposures (AUC) of velpatasvir were approximately 23 (mice), 4 (rats), and 0.5 (rabbits) times the exposure in humans at the RHD, while exposures of voxilaprevir were approximately 141 (rats) and 4 (rabbits) times the exposure in humans at the RHD. Exposures of the predominant circulating metabolite of sofosbuvir (GS-331007) were approximately 6 (rats) and 16 (rabbits) times the exposure in humans at the RHD.

In rat pre/postnatal development studies, maternal systemic exposures (AUC) for each component of VOSEVI were approximately 7 (sofosbuvir metabolite GS-331007), 3 (velpatasvir), and 238 (voxilaprevir) times the exposure in humans at the RHD. The background risk of major birth defects and miscarriage for the indicated population is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2–4% and 15–20%, respectively.

Data Sofosbuvir: Sofosbuvir was administered orally to pregnant rats (up to 500 mg/kg/day) and rabbits (up to 300 mg/kg/day) on gestation days 6 to 18 and 6 to 19, respectively, and also to rats (oral doses up to 500 mg/kg/day) from gestation day 6 to lactation/post-partum day 20. No significant effects on embryo-fetal (rats and rabbits) or pre/postnatal (rats) development were observed at the highest doses tested. The systemic exposures (AUC) of the predominant circulating metabolite of sofosbuvir (GS-331007) during gestation were approximately 6 (rats) and 16 (rabbits) times the exposure in humans at the RHD.

Velpatasvir: Velpatasvir was administered orally to pregnant mice (up to 1000 mg/kg/day), rats (up to 200 mg/kg/day) and rabbits (up to 300 mg/kg/day) from gestation days 6 to 15, 6 to 17, and 7 to 20, respectively, and also to rats (oral doses up to 200 mg/kg) on gestation day 6 to lactation/post-partum day 20. No significant effects on embryo-fetal (mice, rats, and rabbits) or pre/postnatal (rats) development were observed at the highest doses tested. The systemic exposures (AUC) of velpatasvir during gestation were approximately 23 (mice), 4 (rats), and 0.5 (rabbits) times the exposure in…