It sounds like a fantasy, but researchers are making headway in the development of an effective, safe and easily manufactured combination anti-heroin/HIV vaccine.
The National Institute on Drug Abuse (NIDA) at the National Institutes of Health (NIH) has chosen Gary R. Matyas, PhD, to receive the NIDA Avant-Garde Award for Medications Development – a $1 million per year grant over five years – to support his research to develop a vaccine that could treat heroin addiction while simultaneously preventing HIV infection among recipients. The award was announced Wednesday at the International AIDS Conference in Washington.
Working with investigators at the U.S. Military HIV Research Program (MHRP), the Walter Reed Army Institute of Research (WRAIR) and NIDA, Matyas will be continuing his research on the use of adjuvants – used to boost immune responses elicited by vaccines – to create this combo vaccine.
The challenges in developing heroin vaccines are primarily due to the fact that heroindoes not induce high antibody responses in the body, Matyas said. His research will build upon “previous preclinical research indicating that hapten-based anti-drug vaccines – in which a small molecule chemically similar to a drug of abuse (hapten) is bound to a protein carrier to induce an immune response – showed promise against a variety of abused drugs, including heroin,” according to a NIDA press release.
“Initial work has demonstrated we can make high antibody levels, much higher than other reports,” Matyas said. “NIDA’s award will allow us to further test those vaccines in animal studies to block heroin and to prevent overdose.”
The HIV vaccine used in the study will be derived from that used in the Thai RV144 trial conducted by U.S. Army investigators that demonstrated about a 30 percent protection level among vaccine recipients. Studies later on found that study participants who produced a certain antibody – which recognizes the V2 loop in HIV’s outer envelope – were 43 percent less likely to become infected with HIV. That vaccine trial work will give the investigators clues to what the immune response is involving protection from HIV.
“We hope to expand upon these findings with our potent adjuvants,” Matyas said, adding that the adjuvants are safe, stable, synthetic and generic. They will then test the antibodies in labs, and test the vaccines in animals, to see if they can block HIV infection.
“We strongly believe that the vaccine will have efficacy, and we will move the studies forward as fast as we can, but typically moving a drug or vaccine through all the clinical stages and approval processes is roughly 10 years or more,” Matyas said.
NIDA is funding more than 90 percent of world research related to substance abuse disorders, said Dr. Nora Volkow, the institute’s director. About $330 million goes toward HIV-related research, mostly due to the ties between injection drug use (IDU) and HIV infection
“A big challenge has been trying to prevent and treat substance abusers as it related to HIV,” she said. If a person is an injecting drug user and is HIV infected, that person is much less likely to receive antiretroviral therapy (ART). Part of this related to stigma, but it also relates to fear that they will be unable to sustain and adhere to HIV treatment, Volkow said.
“A vaccine would enable immunization of an individual that has a history of IDU with heroin against the heroin itself, such that the antibodies would interfere with the drug absorption in the brain.” The potential of this combination vaccine could me most acutely felt outside of sub-Saharan Africa – including the former Soviet Union and southeast Asia – where injection drug use is the major driver of new HIV infections.