Sofosbuvir: uses, dosing, side effects & brands

The following serious adverse reactions are described below and elsewhere in the labeling: Serious Symptomatic Bradycardia When Coadministered with Amiodarone [see Warnings and Precautions (5.2) ] . The most common adverse events (incidence greater than or equal to 20%, all grades) observed with SOVALDI in combination with ribavirin were fatigue and headache. The most common adverse events observed with SOVALDI in combination with peginterferon alfa and ribavirin were fatigue, headache, nausea, insomnia and anemia. ( 6.1 ). The most common adverse events observed with SOVALDI in combination with ribavirin oral solution in pediatric patients was decreased appetite. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Gilead Sciences, Inc. at 1-800-GILEAD-5 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. When SOVALDI is administered with ribavirin or peginterferon alfa/ribavirin, refer to the respective prescribing information for a description of adverse reactions associated with their use. Adverse Reactions in Adult Subjects The safety assessment of SOVALDI was based on pooled Phase…

When SOVALDI is used in combination with ribavirin or peginterferon alfa/ribavirin, the contraindications applicable to those agents are applicable to combination therapies. Refer to the prescribing information of peginterferon alfa and ribavirin for a list of their contraindications. When used in combination with peginterferon alfa/ribavirin or ribavirin alone, all contraindications to peginterferon alfa and/or ribavirin also apply to SOVALDI combination therapy. ( 4 )

Coadministration of amiodarone with a sofosbuvir-containing regimen may result in serious symptomatic bradycardia. ( 5.2 , 6.2 , 7.1 ) Drugs that are intestinal P-gp inducers (e.g., rifampin, St. John's wort) may alter the concentrations of sofosbuvir. ( 5.3 , 7 , 12.3 ) Consult the full prescribing information prior to use for potential drug-drug interactions. ( 5.2 , 5.3 , 7 , 12.3 ) 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. ( 7.1 ) 7.1 Potentially Significant Drug Interactions Sofosbuvir is a substrate of drug transporter P-gp and breast cancer resistance protein (BCRP) while the predominant circulating metabolite GS-331007 is not. Drugs that are P-gp inducers in the intestine (e.g., rifampin or St. John's wort) may decrease sofosbuvir plasma concentration, leading to reduced therapeutic effect of SOVALDI, and thus concomitant use with SOVALDI is not recommended [see Warnings and Precautions (5.3) ] . 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. Information on potential drug interactions with SOVALDI is summarized in Table 7. The table is not all-inclusive [see Warnings and Precautions (5.2 , 5.3) and Clinical Pharmacology (12.3) ]. Table 7 Potentially Significant Drug Interactions: Alteration in Dosage 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. Clinical Comment Antiarrhythmics: amiodarone Effect on amiodarone and sofosbuvir concentrations unknown Coadministration of amiodarone with a sofosbuvir-containing regimen may result in serious symptomatic bradycardia. The mechanism of this effect is unknown. Coadministration of amiodarone with SOVALDI is not recommended; if coadministration is required, cardiac monitoring is recommended [see Warnings and Precautions (5.2) , Adverse Reactions (6.2) ]. Anticonvulsants: Carbamazepine phenytoin phenobarbital oxcarbazepine ↓ sofosbuvir ↓ GS-331007 Coadministration of SOVALDI with carbamazepine, phenytoin, phenobarbital or oxcarbazepine is expected to decrease the concentration of sofosbuvir, leading to reduced therapeutic effect of SOVALDI. Coadministration is not recommended. Antimycobacterials: Rifabutin rifampin rifapentine ↓ sofosbuvir ↓ GS-331007 Coadministration of SOVALDI with rifabutin or rifapentine is expected to decrease the concentration of sofosbuvir, leading to reduced therapeutic effect of SOVALDI. Coadministration is not recommended. Coadministration of SOVALDI with rifampin, an intestinal P-gp inducer, is not recommended [see Warnings and Precautions (5.3) ]. Herbal Supplements: St. John's wort (Hypericum perforatum) ↓ sofosbuvir ↓ GS-331007 Coadministration of SOVALDI with St. John's wort, an intestinal P-gp inducer, is not recommended [see Warnings and Precautions (5.3) ]. HIV Protease Inhibitors: tipranavir/ritonavir ↓ sofosbuvir ↓ GS-331007 Coadministration of SOVALDI with tipranavir/ritonavir is expected to decrease the concentration of sofosbuvir, leading to reduced therapeutic effect of SOVALDI. Coadministration is not recommended. 7.2 Drugs without Clinically Significant Interactions with SOVALDI Based on drug interaction studies conducted with SOVALDI, no clinically significant drug interactions have been either observed or are expected when SOVALDI is combined with the following drugs [see Clinical Pharmacology (12.3) ]: cyclosporine, darunavir/ritonavir, efavirenz, emtricitabine, methadone, oral contraceptives, raltegravir, rilpivirine, tacrolimus, or tenofovir disoproxil fumarate.