Chimerix Inc has licensed rights from Gilead Sciences Inc to develop oral derivatives of Gilead's proprietary antiviral compound cidofovir, intended for the prevention or treatment of smallpox infections. Chimerix's initial focus will be to continue the development of its oral smallpox drug, CMX-001, which is a chemically modified derivative of cidofovir, derived by incorporating Chimerix proprietary chemistry to enhance intracellular uptake and oral delivery.

The license permits Chimerix to sell CMX-001 to governments anywhere in the world. The license also includes the rights to develop and sell oral derivatives of cidofovir for treatment of infections caused by related viruses such as vaccinia virus (the virus used for smallpox vaccinations) and monkeypox virus (a smallpox-related virus found in animals, which can be passed on to humans). Chimerix will pay Gilead royalties based on a percentage of net sales to governments. Specific terms of the agreement were not disclosed.

Cidofovir is an antiviral medication currently approved for the treatment of cytomegalovirus (CMV) retinitis in AIDS patients. Marketed under the brand name Vistide, Gilead's drug was cleared for marketing by the U.S. Food and Drug Administration in 1996 and by European regulators in 1997. Cidofovir is administered by intravenous infusion. Using proprietary technology, Chimerix is able to modify cidofovir (the parent compound), to yield a potent, orally available drug that has the potential to treat smallpox infections, or complications of smallpox vaccination.

Chimerix was recently awarded a $36.1M grant from U.S. National Institute of Allergy and Infectious Diseases (NIAID) of the National Institutes of Health (NIH), under the Bioterrorism Act of 2002, to support development for its drug, CMX-001, as a treatment for smallpox. The Bioterrorism Act of 2002 authorizes government spending for the National Pharmaceutical Stockpile.

"Chimerix's lead drug candidate is a chemically modified version of cidofovir that has the potential to be the first effective and non-toxic oral therapy for smallpox infections. This is significant, as over 40 million Americans who are pregnant, have eczema or whose immune systems are compromised in any way are not candidates for vaccination," said George Painter, CEO of Chimerix. "Pending further positive studies, we also hope to demonstrate that CMX-001 will be both a preventive drug and a potential treatment for people who develop complications from vaccinia, the virus used in the smallpox vaccine."