Promise in development of AIDS vaccine - Phase I clinical trial shows encouraging outcome
Saturday, August 16th, 2008The results of the trial of an MVA-based AIDS vaccine candidate (TBC-M4), which was conducted in Chennai, indicated that the vaccine candidate had acceptable levels of safety and was well tolerated.
The proportion of volunteers whose immune systems responded to the vaccine candidate suggests the candidate holds promise. The trial was done using two doses of the candidate vaccine. After three injections, 82 percent of the volunteers who received a low dose and 100 percent of those who received a high dose registered immune responses to the vaccine. The 100 percent response rate is greater than that seen with the majority of AIDS vaccine candidates tested in humans to date. However the strength and diversity of these immune responses were modest. It may be possible to boost the immune response, if this vaccine is used in combination with other candidate AIDS vaccines.
The Phase I clinical trial was initiated in January 2006 at the Tuberculosis Research Center (TRC), an Indian Council of Medical Research (ICMR) institute in Chennai, and was completed in February 2008. This trial was conducted under the aegis of a Memorandum of Understanding (MoU) between the Government of India—through the Indian Council of Medical Research (ICMR) and the National AIDS Control Organization (NACO)—and the not-for-profit International AIDS Vaccine Initiative (IAVI). YRG CARE, based in Chennai, collaborated with TRC to mobilize the community around the Phase I trial.
About the Phase I MVA-based (TBC-M4) AIDS vaccine trial
The trial was a double blind, dose-escalation, randomized, placebo-controlled trial, which was initiated after receiving all necessary regulatory and ethical clearances. The objectives of such a Phase I trial are to evaluate the safety of the vaccine candidate and to gather preliminary results of immune responses induced by the candidate. The total duration of the trial was approximately 24 months. The volunteers recruited for this trial were 32 healthy, HIV-uninfected men and women between 18 and 50 years of age, from all socio-economic strata. Three intra-muscular injections of TBC-M4 or placebo were administered to the volunteers.
