Columbia's AIDS Drug Enters Ph II/III In UK

Columbia Laboratories of Miami, USA, has progressed its drug for the prevention of progression to AIDS in late-stage HIV-infected patients, SPC3, into Phase II/III clinical trials. The studies will be conducted at the Charing Cross AIDS Centre in London, UK.

SPC3 consists of an eight-chain peptide polymer, containing eight repeats of the consensus region of the V3 loop of HIV-1 gp120, a viral surface envelope glycoprotein. Columbia believes that the compound acts by blocking receptors on the surface of lymphocytes and preventing the fusion of HIV-1. The polymer also prevents HIV-1 from penetrating into macrophages and intestinal cells, according to Columbia. It is thought that neurological involvement in HIV infection arises as a result of infected macrophages carrying the virus past the blood brain barrier so, in theory, SPC3 can passively control the spread of the virus in both the lymphatic and central nervous systems.

SPC3 was originally discovered by a team of researchers from the Centre Nationale de Recherche Scientifique in Marseille, France, which licenses the product to Columbia. This team has also developed a combination molecule, CDR5, made up SPC3 and another synthetic polymer SPC5, which are combined to form a multibranched polymer. Jacques Fantini, a virologist and member of the French team, has noted that not only can CDR5 block the infection of the target cells by HIV-1 but also HIV-2, according to in vitro studies.