In 1991 and 1992, Gilead licensed the rights to a family of nucleotide analogue compounds from two research institutions in the Czech Republic and Belgium. These compounds became the foundation for our research and development program, and soon led to the development of Gilead's first products for HIV and hepatitis B (HBV).
Nucleotides are the building blocks of DNA and RNA. By chemically modifying nucleotides' complex structural elements, Gilead has been able to design nucleotide analogues that, unlike naturally present nucleotides, inhibit viral replication. Our pioneering research led to the development of Vistide® for cytomegalovirus retinitis in patients with AIDS (1996), Viread® for HIV (2001) and Hepsera® for HBV (2002).
Gilead is also continuing research into a closely related family of compounds called nucleoside analogues. Another of our HIV products, Emtriva®, was developed using nucleoside analogue technology. Gilead researchers have since designed and developed innovative fixed-dose combinations of nucleotide and nucleoside analogues in order to simplify HIV therapy, including Truvada® (2004) and Atripla™ (2006).
HIV/AIDS
In HIV/AIDS our current research efforts are focused in two main areas:
New Drug Classes
We are focused on expanding our successful HIV/AIDS franchise through the addition of novel drugs that target different mechanisms within the HIV replication cycle. Today, Gilead's most advanced pipeline candidate for HIV is an integrase inhibitor called elvitegravir (GS 9137). Integrase inhibitors are a potential new class of antiretroviral product that target a different stage in the HIV replication cycle than other available classes of drugs, and may, when combined with other medications, effectively prevent viral replication in patients currently resistant to other treatments. Integrase inhibitors block the integrase enzyme that HIV uses to integrate its genetic material with the DNA of human cells, thereby preventing HIV from replicating itself. In early 2007, Gilead announced the successful completion of a Phase II clinical trial of elvitegravir.
Existing Classes
At Gilead, we feel it is important to continue to generate long-term clinical data for our marketed products that demonstrate our products' safety, efficacy and resistance profiles. We believe that by providing long-term data, physicians and their patients will be able to make more informed treatment decisions.
Gilead continues to pioneer leading research in a key area of HIV: resistant virus. It has become increasingly important to fully understand the potential patterns of cross-resistance between the classes of commercially available HIV drugs and those in development. And our researchers continue to review and work to develop drugs that have a decreased propensity to select viral resistant strains.
Hepatitis
HBV
Today, Gilead's HBV R&D program is focused on Viread®. Data generated from our HIV trials for Viread indicate that it has the potential to suppress HBV in patients co-infected with HIV and HBV. In June 2006, Gilead completed enrollment of two Phase III clinical trials (Studies 102 and 103) to evaluate Viread for the treatment of HBV.
HCV
Gilead is currently focused on the development of non-nucleoside HCV polymerase inhibitors - compounds that block an enzyme essential for HCV replication. We are currently evaluating GS 9190 in HCV-infected individuals. We are also partnering with Achillion Pharmaceuticals to develop additional candidates to combat HCV. |
