FDA warns about serious reactions to Harvoni, Sovaldi

March 25, 2015

Both the Food and Drug Administration (FDA) and Harvoni and Sovaldi maker Gilead are warning Hepatitis C patients about serious bradycardia when the drugs are combined with certain other medications.

FDA and Harvoni and Sovaldi manufacturer Gilead are warning hepatitis C patients about serious bradycardia when the drugs are combined with certain other medications.

Serious slowing of the heart rate can occur when the antiarrhythmic drug amiodarone is taken together with either Harvoni (ledipasvir/sofosbuvir) or Sovaldi (sofosbuvir), taken in combination with another direct-acting antiviral (DAA) for the treatment of hepatitis C, according to the FDA. “Health care professionals should not prescribe either Harvoni or Sovaldi combined with another direct-acting antiviral drug with amiodarone,” FDA said in a MedWatch Safety Alert issued Monday.

Cases of symptomatic bradycardia, as well as one fatal cardiac arrest and cases requiring pacemaker insertion, have been reported in patients taking amiodarone and Harvoni, or amiodarone and Sovaldi in combination with another DAA, according to Gilead. Steven patients were also receiving a beta blocker.

The other patients recovered after discontinuing either the hepatitis C drugs or amiodarone, or both. “The cause of these events could not be determined. FDA will continue to monitor Harvoni and Sovaldi for risks of serious symptomatic bradycardia and further investigate the reason why the use of amiodarone with these hepatitis C drugs led to the heart-related events,” the agency stated.

Related:CVS Health commits to Gilead's hepatitis C drugs

This new information on Harvoni and Sovaldi underscores the need for payers to incorporate FDA adverse events data into formulary decisions and prior authorization guidelines, according to Kip Piper, senior advisor with Sellers Dorsey and consultant for AdverseEvents, a drug safety firm. 

“The new hepatitis C drugs offer tremendous clinical value, but it is vital that states and others are able to consider adverse events, not just net unit prices, in distinguishing between available therapies,” Piper said. “Otherwise, state Medicaid agencies and health plans in the Medicaid, Medicare, and commercial space will make decisions on unit price only – unaware of the medical costs from adverse events.” 

FDA is adding information about symptomatic bradycardia to the Harvoni and Sovaldi labels.

In cases where alternative treatment options are unavailable, FDA recommends heart monitoring in an inpatient hospital setting for the first 48 hours. Subsequently, monitoring in a doctor’s office or self-monitoring of the heart rate should be done every day through at least the first 2 weeks of treatment.

Related: Anthem strikes deal with Gilead Sciences making Harvoni the primary treatment for hep C

Due to the long half-life of amiodarone, patients discontinuing amiodarone just prior to starting Harvoni, or Sovaldi in combination with another DAA, should also undergo similar cardiac monitoring, FDA said.

Read next: Class action suit latest problem with Sovaldi