A Phase III clinical trial of Gilead Science’s once-daily experimental integrase inhibitor elvitegravir is now open and enrolling patients, according to a press release issued yesterday by the company. The company also announced plans to study a novel boosting agent that can potentially be used as an alternative to Abbott Laboratories’ expensive and side effect-prone Norvir (ritonavir).
In order for HIV to successfully take over a CD4 cell’s machinery so that it can produce new viruses, HIV’s RNA must be converted into DNA by the reverse transcriptase enzyme (nucleoside reverse transcriptase inhibitors—NRTIs—can block this process). After the reverse transcription of RNA into DNA is complete, HIV’s DNA must then be incorporated into the CD4 cell’s DNA. This is known as integration. As their name implies, integrase inhibitors work by blocking this process.
Elvitegravir, also known as GS-9137 and JTK 303, is the second integrase inhibitor to be studied in large-scale clinical trials and to show promise for HIV-positive people with drug-resistant virus and limited treatment options. Gilead is hoping to show that elvitegravir, given once daily with a low dose of Norvir, is no less effective than Merck’s twice-daily integrase inhibitor Isentress (raltegravir), which was approved by the U.S. Food and Drug Administration in October 2007.
The current study will enroll 700 treatment-experienced HIV-positive patients at about 125 sites in the United States and Puerto Rico. Participants will receive either once-daily elvitegravir or twice-daily raltegravir and, based on the results of drug-resistance and tropism testing, a Norvir-boosted protease inhibitor with an NRTI, Intelence (etravirine), Selzentry (maraviroc) or Fuzeon (enfuvirtide).
A second Phase III study with a similar design will be initiated later this year in Europe, Canada and Australia.
Gilead also announced that it is developing its own compound, dubbed GS 9350, that may be used as an alternative to Norvir to boost the blood levels and effectiveness of other antiretrovirals. If GS 9350 proves to be a safe and effective alternative to ritonavir for boosting purposes, Gilead plans to coformulate the drug with its other HIV drugs, including elvitegravir, Viread (tenofovir), Emtriva (emtricitabine) and Truvada (tenofovir/emtricitabine).
More information about the U.S. elvitegravir Phase III study is available on the National Institutes of Health’s ClinicalTrials.gov website. Click here for study details.
NEW! Scroll down to comment on this story.
Please click OK to confirm your comment and confirm you accept our posting rules. Note your message will be reviewed by our staff before going live.
Beth Benne, RN, is HIV negative, but
the virus has impacted her life. She currently supervises a biannual HIV/AIDS awareness week as
the director of the student health center at Pierce College, a
community commuter school in Woodland Hills, California.
Woman of the Month is supported by exclusive advertising from Gilead.
Overheard in the Women's Forum
"I recently met a guy who is negative. I did tell him about my status and he decided to kiss me anyway (we didn't go further than that). But a day later, he called and said that he actually had a mouth ulcer that time when we kissed and he was very worried. Asked if he can get the virus from me that way. For that moment, I felt so insulted and yet I felt so bad. It was my first time having a contact with a "negative" guy."
