Further trials on prime-boost AIDS vaccine being tested in Pune and Chennai have been suspended after Phase I trial results showed that the vaccine candidate is too unstable to be scaled up.
"The vaccine is safe and elicits a modest immune response against HIV, the virus that causes AIDS, but simulated large-scale manufacturing studies of the gene insert (TBC-M4) made the vaccine unstable, which means it cannot be mass produced,” Rajat Goyal, country director, International AIDS Vaccine Initiative (IAVI), told Hindustan Times.
IAVI is the research partner for the vaccine trials that took place at the National AIDS Research Institute (NARI), Pune, and National Institute for Research in Tuberculosis, Chennai.
Phase I trials are conducted on healthy people between the ages of 18 and 50 years to establish safety for human use The findings will be presented on September 14 at the AIDS Vaccine 2011 conference in Bangkok.
Group A received ADVAX, a DNA-based vaccine, as prime and Modified Vaccinia Ankara (MVA) as boost. Group B received the MVA as a prime and boost. No added advantage of DNA priming was found.
Overall, the effectiveness lasted at the end of one year from the date of the last injection in both the groups.
"The fact that the prime boost vaccine works in the Indian population makes us hopeful that it can be used for other vaccine candidates,” said Goyal.