The National Institutes of Health (NIH) has awarded Texas Biomedical Research Institute (Texas Biomed) and research fellows at Food & Drug Administration (FDA), the University of California, Los Angeles (UCLA) and the University of Pennsylvania (UPENN), a $5 million grant for a four-year research study on combined approach based on antiviral drugs and investigational AIDS (acquired immune deficiency syndrome) vaccines for children and infants infected with HIV.
The World Health Organization (WHO) estimated there were nearly 37 million people with AIDS in the world in 2014, of which 2.6 million were children. WHO believes 220,000 children became infected just in 2014.
Dr. Ruth Ruprecht, Scientist & Director of the Texas Biomed AIDS Research Program and lead investigator of the project, commented in a press release: “Our goal is to determine whether these candidate vaccines, partnered with antiviral drugs, will not only completely suppress HIV replication in babies infected with HIV at birth, but will also induce such strong antiviral cellular immune defenses that the virus will not reemerge after all treatment is stopped, (…) We will test our concepts in infant and neonatal rhesus monkeys. These primate models will allow us to assess whether the virus can be cleared from tissue reservoirs and whether long-lasting protective immunity has been generated by the combined treatment.”
There is still no cure or vaccine against HIV, although there are highly active anti-retroviral therapies (HAART) available. HAART is effective at inhibiting and suppressing virus replication, but as soon as a patient stops treatment, the virus returns.
Dr. Ruprecht explained the plan for the study, “We will provide HAART to infant monkeys to suppress the virus so the animals will no longer be viremic (show virus in the blood). Once the virus is shown to be suppressed, we will give them a combination rubella vaccine that has pieces of the SHIV (simian human immunodeficiency virus) inserted into the vaccine. This vaccine vector is so potent it induces a very strong immune response. Once HAART is stopped, our hope is that the vaccine-induced immune cells take over.”
Investigators expect that, due to the vaccination, the immune system will recognize viral proteins exhibited on HIV-infected cells, so that the immune T-cells in the body can kill the infected cells. “We are planning to induce strong killer cell activity,” noted Dr. Ruprecht. “These cells will patrol the body and take out AIDS virus-infected cells that become activated once HAART has been stopped. We hope over time this patrolling and cell killing will shrink the virus reservoir and there will be fewer cells left in the body able to activate the virus.”
Besides Dr. Ruprecht, Ira Berkower, MD, PhD, affiliated with the FDA, is also coordinating the study. Dr. Berkower participated in the inaugural testing of the rubella vector-based vaccine together with Yvonne J. Bryson, MD, Chief of Pediatric Infectious Diseases at UCLA and Sarah J. Ratcliffe, PhD, Associate Professor of Biostatistics at UPENN, who will provide biostatistical input to the study. The team expects that this combined therapy will lead to an effective cure, where the virus and its negative effects will be eliminated, without the patient needing continued HAART treatment. Additionally, researchers hope this therapy will provide immunity against future HIV exposure. “We are excited to launch this study and develop an attack plan against HIV that could both cure and provide a solid defense against further infection,” concluded Dr. Ruprecht.