Sofosbuvir
Brand names: Sovaldi
Boxed warning
WARNING: RISK OF HEPATITIS B VIRUS REACTIVATION IN PATIENTS COINFECTED WITH HCV AND HBV Test all patients for evidence of current or prior hepatitis B virus (HBV) infection before initiating treatment with SOVALDI. HBV reactivation has been reported in HCV/HBV coinfected patients who were undergoing or had completed treatment with HCV direct acting antivirals and were not receiving HBV antiviral therapy. Some cases have resulted in fulminant hepatitis, hepatic failure, and death. Monitor HCV/HBV coinfected patients for hepatitis flare or HBV reactivation during HCV treatment and post-treatment follow-up. Initiate appropriate patient management for HBV infection as clinically indicated [see Warnings and Precautions (5.1) ] . WARNING: RISK OF HEPATITIS B VIRUS REACTIVATION IN PATIENTS COINFECTED WITH HCV AND HBV See full prescribing information for complete boxed warning. Hepatitis B virus (HBV) reactivation has been reported, in some cases resulting in fulminant hepatitis, hepatic failure, and death. ( 5.1 )
Warnings
5 WARNINGS AND PRECAUTIONS Risk of Hepatitis B Virus Reactivation: Test all patients for evidence of current or prior HBV infection before initiation of HCV treatment. Monitor HCV/HBV coinfected patients for HBV reactivation and hepatitis flare during HCV treatment and post-treatment follow-up. Initiate appropriate patient management for HBV infection as clinically indicated. ( 5.1 ) Bradycardia with amiodarone coadministration: Serious symptomatic bradycardia may occur in patients taking amiodarone with a sofosbuvir-containing regimen, particularly in patients also receiving beta blockers, or those with underlying cardiac comorbidities and/or advanced liver disease. Coadministration of amiodarone with SOVALDI is not recommended. In patients without alternative, viable treatment options, cardiac monitoring is recommended. ( 5.2 , 6.2 , 7.1 ) 5.1 Risk of Hepatitis B Virus Reactivation in Patients Coinfected with HCV and HBV Hepatitis B virus (HBV) reactivation has been reported in HCV/HBV coinfected patients who were undergoing or had completed treatment with HCV direct acting antivirals, and who were not receiving HBV antiviral therapy. Some cases have resulted in fulminant hepatitis, hepatic failure, and death. Cases have been reported in patients who are HBsAg positive and also in patients with serologic evidence of resolved HBV infection (i.e., HBsAg negative and anti-HBc positive). HBV reactivation has also been reported in patients receiving certain immunosuppressant or chemotherapeutic agents; the risk of HBV reactivation associated with treatment with HCV direct-acting antivirals may be increased in these patients. HBV reactivation is characterized as an abrupt increase in HBV replication manifesting as a rapid increase in serum HBV DNA level. In patients with resolved HBV infection, reappearance of HBsAg can occur. Reactivation of HBV replication may be accompanied by hepatitis, i.e., increases in aminotransferase levels and, in severe cases, increases in bilirubin levels, liver failure, and death can occur. Test all patients for evidence of current or prior HBV infection by measuring HBsAg and anti-HBc before initiating HCV treatment with SOVALDI. In patients with serologic evidence of HBV infection, monitor for clinical and laboratory signs of hepatitis flare or HBV reactivation during HCV treatment with SOVALDI and during post-treatment follow-up. Initiate appropriate patient management for HBV infection as clinically indicated. 5.2 Serious Symptomatic Bradycardia When Coadministered with Amiodarone Postmarketing cases of symptomatic bradycardia and cases requiring pacemaker intervention have been reported when amiodarone is coadministered with a sofosbuvir-containing regimen. A fatal cardiac arrest was reported in a patient taking amiodarone who was coadministered a sofosbuvir-containing regimen (HARVONI [ledipasvir/sofosbuvir]). Bradycardia has generally occurred within hours to days, but cases have been observed up to 2 weeks after initiating HCV treatment. Patients also taking beta blockers, or those with underlying cardiac comorbidities and/or advanced liver disease may be at increased risk for symptomatic bradycardia with coadministration of amiodarone. Bradycardia generally resolved after discontinuation of HCV treatment. The mechanism for this effect is unknown. Coadministration of amiodarone with SOVALDI is not recommended. For patients taking amiodarone who have no other alternative, viable treatment options and who will be coadministered SOVALDI: Counsel patients about the risk of serious symptomatic bradycardia Cardiac monitoring in an in-patient setting for the first 48 hours of coadministration is recommended, after which outpatient or self-monitoring of the heart rate should occur on a daily basis through at least the first 2 weeks of treatment. Patients who are taking SOVALDI who need to start amiodarone therapy due to no other alternative, viable treatment options should undergo similar cardiac monitoring as outlined above. Due to amiodarone's long half-life, patients discontinuing amiodarone just prior to starting SOVALDI should also undergo similar cardiac monitoring as outlined above. Patients who develop signs or symptoms of bradycardia should seek medical evaluation immediately. Symptoms may include near-fainting or fainting, dizziness or lightheadedness, malaise, weakness, excessive tiredness, shortness of breath, chest pains, confusion or memory problems [see Adverse Reactions (6.2) , Drug Interactions (7.1) ] . 5.3 Risk of Reduced Therapeutic Effect Due to Use with P-gp Inducers Drugs that are P-gp inducers in the intestine (e.g., rifampin, St. John's wort) may significantly decrease sofosbuvir plasma concentrations and may lead to a reduced therapeutic effect of SOVALDI. The use of rifampin and St. John's wort with SOVALDI is not recommended [see Drug Interactions (7.1) ] . 5.4 Risks Associated with Combination Treatment Because SOVALDI is used in combination with other antiviral drugs for treatment of HCV infection, consult the prescribing information for these drugs used in combination with SOVALDI. Warnings and Precautions related to these drugs also apply to their use in SOVALDI combination treatment.
Contraindications
4 CONTRAINDICATIONS 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 )
Overdose
10 OVERDOSAGE The highest documented dosage of sofosbuvir was a single dose of sofosbuvir 1200 mg (three times the recommended dosage) administered to 59 healthy subjects. In that trial, there were no untoward effects observed at this dosage level, and adverse events were similar in frequency and severity to those reported in the placebo and sofosbuvir 400 mg treatment groups. The effects of higher dosages are not known. No specific antidote is available for overdose with SOVALDI. If overdose occurs, the patient must be monitored for evidence of toxicity. Treatment of overdose with SOVALDI consists of general supportive measures including monitoring of vital signs as well as observation of the clinical status of the patient. A 4-hour hemodialysis session removed 18% of the administered dose.
Drug interactions
7 DRUG INTERACTIONS 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.
Uses
1 INDICATIONS AND USAGE SOVALDI is a hepatitis C virus (HCV) nucleotide analog NS5B polymerase inhibitor indicated for the treatment of: Adult patients with genotype 1, 2, 3 or 4 chronic HCV infection without cirrhosis or with compensated cirrhosis as a component of a combination antiviral treatment regimen. ( 1 ) Pediatric patients 3 years of age and older with genotype 2 or 3 chronic HCV infection without cirrhosis or with compensated cirrhosis in combination with ribavirin. ( 1 ) Adult Patients: SOVALDI is indicated for the treatment of adult patients with chronic hepatitis C virus (HCV) infection as a component of a combination antiviral treatment regimen [see Dosage and Administration (2.2) , and Clinical Studies (14) ]: genotype 1 or 4 infection without cirrhosis or with compensated cirrhosis for use in combination with pegylated interferon and ribavirin genotype 2 or 3 infection without cirrhosis or with compensated cirrhosis for use in combination with ribavirin. Pediatric Patients: SOVALDI is indicated for the treatment of chronic HCV genotype 2 or 3 infection in pediatric patients 3 years of age and older without cirrhosis or with compensated cirrhosis for use in combination with ribavirin [see Dosage and Administration (2.3) and Clinical Studies (14.5) ] .