What is Racivir?
- Racivir is an anti-HIV medication. It is in a category of HIV medicines called nucleoside reverse transcriptase inhibitors (NRTIs). Racivir prevents HIV from entering the nucleus of healthy T-cells. This prevents the cells from producing new virus and decreases the amount of virus in the body.
- Racivir is being developed by Pharmasset. It has not yet been reviewed by the U.S. Food and Drug Administration.
What is already known about Racivir?
- The necessary dose of Racivir has not yet been determined. Racivir will most likely only need to be taken once a day.
- Racivir's chemical structure is similar to that of Epivir® (3TC) and Emtriva® (emtricitabine). It is not clear if Racivir will be effective against HIV that is already resistant to Epivir or Emtriva.
- Racivir is also active against the hepatitis B virus (HBV), the virus responsible for hepatitis B. It has not been extensively studied or approved for the treatment of HBV.
- Like other nucleoside reverse transcriptase inhibitors (NRTIs), Racivir might interact with other medications, including those used to treat HIV. It is important that your personal physician and/or the research nurse or study investigator be aware of all drugs you are taking, including those you buy without a prescription.
What has been learned from clinical trials?
- A Phase I single-dose study in healthy volunteers demonstrated that Racivir was safe and well-tolerated at all doses studied.
- In a Phase Ia/IIb study, 18 HIV-positive people who had not taken other anti-HIV drugs in the past took one of three doses of Racivir (200mg, 400mg, or 600mg) once a day in combination with Sustiva® (efavirenz) and Zerit® (d4T). Treatment was continued for 14 days and then stopped. After 14 days of treatment, viral loads dropped by approximately 2 logs in all patients. On day 35 (20 days after stopping treatment), all patients had viral loads that were still 1 log below their pre-treatment levels.
- A Phase II study (RCV-201) of Racivir is currently being conducted. It is being conducted in the United States, Argentina, Mexico, and Panama, and will include 60 patients. It will evaluate the safety and effectiveness of substituting Racivir for Epivir® (3TC) in treatment-experienced HIV-infected individuals (including patients with the M184V mutation that causes resistance to Epivir).
What is known about side effects?
- Very little is known about the possible side effects of Racivir.
Who should not take Racivir?
- It is not known whether Racivir will harm an unborn baby. It is very important to treat HIV/AIDS during pregnancy to reduce the risk of infecting your baby. Talk to your doctor about your treatment options.
- It is not known whether Racivir passes into breast milk and what effect it may have on a nursing baby. To prevent transmission of the virus to uninfected babies, it is recommended that HIV-positive mothers not breast-feed.
Where can I learn more about clinical trials of Racivir?
- If you would like to find out if you are eligible for any clinical trials that include Racivir, there is an interactive web site run by ACRIA, the AIDS Community Research Initiative of America.
- Another useful service for finding clinical trials is AIDSinfo.nih.gov, a site run by the U.S. National Institutes of Health. They have "health information specialists" you can talk to at their toll-free number at 1-800-HIV-0440 (1-800-448-0440).