EMA recommends new Rxing info on Victrelis and warnings for aliskiren

The European Medicines Agency has recommended updating the prescribing information for US drug giant Merck & Co’s (NYSE: MRK) chronic hepatitis C drug Victrelis (boceprevir) with information about drug interactions between this product and the ritonavir-boosted HIV protease inhibitors atazanavir, darunavir and lopinavir. The drug was approved by the EMA last year (The Pharma Letter July 20, 2011).

A drug interaction study in healthy volunteers carried out by Merck’s Merck Sharp and Dohme unit, the marketing authorization holder of Victrelis, found that blood levels of all three HIV medicines were markedly lower than expected when given with Victrelis. It also found that blood levels of Victrelis were markedly lower than expected when given with ritonavir-boosted darunavir or lopinavir, although this effect was not seen with ritonavir-boosted atazanavir.

The Agency's Committee for Medicinal Products for Human Use (CHMP) concluded that the lower blood levels seen in the drug interaction study could mean that the medicines are less effective when given together to patients who are co-infected with hepatitis C and HIV. However, the CHP acknowledged that data from ongoing clinical studies in co-infected patients are needed to assess the clinical impact of these drug-interaction findings on these patients.