Panacos was engaged in the discovery, development and commercialization of small molecule drugs to treat or prevent serious infectious disease. Its lead antiviral product was PA-457, which at the time was the first in a new class of drugs to treat HIV infection. Pappas Ventures teamed up with Ampersand Ventures to take Panacos public via a reverse merger with V.I. Technologies in 2005.

The rights to Panacos’s HIV program were acquired by Myriad Pharmaceuticals in 2009.