Hybridon's GEM 91 Moves Into Phase II

Hybridon's flagship antisense compound, GEM 91, is moving into a PhaseII clinical trial in advanced-stage HIV-positive patients, reported the company at the IBC Oligonucleotide and Gene Therapy-based Antisense Therapeutics meeting in San Diego, where it also presented interim data from its ongoing Phase Ib/II study with the compound.

Data demonstrated a statistically significant decrease in cellular viremia in treated patients compared to untreated patients, which returned to baseline following therapy. In addition, it was noted that the plasma concentration of viral RNA increased during treatment, and reverted after therapy.

This response may occur because GEM 91, given systemically, concentrates in macrophages which are known to harbor the virus after combination therapy, says the company. According to Robert Coombs of the University of Washington in Seattle, "seeing a drop in cell-associated virus with GEM 91 treatment is an encouraging finding."