|What is cenicriviroc?
- Cenicriviroc is an experimental entry inhibitor being developed by Tobira Therapeutics.
- Cenicriviroc primarily works by binding to a receptor on the membrane of CD4 cells called CCR5. Once it does this, HIV cannot successfully bind with the surface of CD4 cells, thus preventing the virus from infecting healthy cells. It also binds with another receptor called CCR2. By blocking this receptor, which has been linked to inflammation in the body, cenicriviroc may also reduce the risk of certain non-AIDS health conditions that are becoming increasingly common among people living with HIV, including cardiovascular disease, neurologic problems, metabolic complications and some cancers.
- Cenicriviroc will need to be used in combination with other HIV drugs.
What is already known about cenicriviroc?
- Two cenicriviroc are currently being explored in a mid-stage clinical trial: 100 mg and 200 mg, taken by mouth once a day. It is likely that cenicriviroc can be taken either with or without food.
- In a Phase IIa trial involving 54 people living with HIV who had been on antiretroviral therapy in the past—though none had been treated with another CCR5-blocking drug (e.g., Selzentry)—a 10-day course of cenicriviroc, in the absence of other medications, decreased viral loads by up to 1.8 log copies. Five doses of the drug were tested in the study (25mg, 50mg, 75mg, 100mg and 150mg) and were compared to a placebo. The 75mg dose appeared to be associated with the most robust reduction in viral load in the study. The 150mg dose, however, lead to the greatest decreases in MCP-1, a protein targeted by CCR2 that is known to jumpstart the immune system inflammation process.However, the study was not designed to determine whether cenicriviroc's CCR2-blocking activity and reductions in MCP-1 helped prevent any health problems.
- A 48-week Phase IIb clinicial trial of cenicriviroc was announced in June 2011. It involves people starting HIV treatment for the first time and is comparing cenicriviroc to Sustiva (efavirenz). Both medications are combined with Truvada (tenofovir plus emtricitabine). In addition to the drug's effects on viral load and CD4 cell counts, the study researchers will look for changes in markers of inflammation, cardiovascular disease measurements and other health outcomes.
- Cenicriviroc is metabolized (broken down) in the body differently than many other HIV medications. In turn, cenicriviroc may not interact negatively with various medications used to treat HIV and other medical problems. Much more information from drug interaction studies are needed, however.
What is known about side effects?
- The side effects of cenicriviroc have not yet been fully determined.
Who should not take cenicriviroc?
- It is not known whether cenicriviroc 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 cenicriviroc 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 cenicriviroc?
- If you would like to find out if you are eligible for any clinical trials that include cenicriviroc, visit ClinicalTrials.gov, a site run by the U.S. National Institutes of Health. The site has information about all HIV-related clinical studies in the United States. For more info, you can call their toll-free number at 1-800-HIV-0440 (1-800-448-0440) or email firstname.lastname@example.org.