Heidelberg's fosalvudine enters Ph II trial

German drug development firm Heidelberg Pharma GmbH has initiated a Phase II clinical study in treatment-naive HIV-infected patients with its enhanced prodrug fosalvudine.

The placebo-controlled, double-blind, study aims to investigate efficacy, tolerability and pharmacokinetics of the agent during a 14-day treatment period. Four dose levels will be tested in a total of 44 HIV patients, who will be enrolled in three subsequent randomization cycles, to see if fosalvudine is capable of reducing viral load. The results are anticipated some time next year.

Heidelberg's drug is a nucleotide reverse transcriptase inhibitor under development for the treatment of HIV-1 infection, with a focus on drug-resistant HIV-1. Fosalvudine generates the same active metabolite as the related compound alovudine, a reverse transcriptase inhibitor that is clinically effective against NRTI-resistant HIV-1 strains with thymidine-associated mutations, but limited by its narrow therapeutic window. Orally-administered, fosalvudine has the potential for a wider use due to reduced side effects at comparable effectiveness, Heidelberg noted.