The Company's researchers have developed a proprietary, high-throughput assay system for discovery of small molecule inhibitors of HIV fusion. Compared to peptide and protein-based inhibitors, orally bioavailable small molecule fusion inhibitors would offer considerable advantages for the treatment of HIV infection, including viral strains resistant to currently approved drugs.  Several novel families of small-molecule HIV fusion inhibitors have been identified using Panacos' screening technology.  These compounds are currently undergoing chemical optimization to develop a clinical candidate, with a goal of IND filing in 2006  Panacos believes it has a leading position in the development of small molecule HIV fusion inhibitors.

Mechanism of Action

The initial steps in HIV replication are mediated by the virus's gp120 and gp41 surface proteins.  The gp120 molecule is involved in cell targeting and binds to CD4 and chemokine receptors.  The membrane fusion event begins when the hydrophobic tip of gp41 penetrates the human cell membrane.  A conformational change in gp41 then pulls the HIV and human cell membranes together to initiate fusion.

Our scientists have identified several classes of potential small molecule HIV fusion inhibitors that block HIV fusion events.

Lead Compound

On March 4, 2007, the Company announced that it had nominated a lead candidate in its fusion inhibitor program.  Panacos plans to move this compound, PA-161, forward into pre-clinical safety testing prior to potential evaluation in human clinical studies.

Publications

Listed below are scientific publications and presentations at scientific meetings.