Advances In Fight Against HIV As Vaccine Heads Into Clinical Trials


By Jonny Lupsha, News Editor

Human trials will begin soon for an HIV vaccine made by Moderna. The treatment is an mRNA vaccine, which means that it teaches the body to trigger an immune response to certain proteins. It is the biggest breakthrough in HIV drugs to date.

The HIV virus is a retrovirus since its genetic material is RNA instead of DNA, which means scientists are now focusing on developing an mRNA vaccine for it. Photo by Rapeepat Pornsipak / Shutterstock

Moderna and several universities, including the University of Texas at San Antonio and George Washington University, have submitted a clinical trial request for a vaccine to treat human immunodeficiency virus (HIV). Officially called mRNA-1644, the treatment will work the same as Moderna and Pfizer’s COVID-19 vaccinations.

The injection instructs the body on how to build a protein specific to the virus, which it does for 24 to 48 hours before recognizing the protein as a foreign object and triggering an immune response. The next time the protein enters the body, in this case in the human immunodeficiency virus, the immune system quickly recognizes it and neutralizes it. Phase 1 trials are only intended to determine whether the vaccine will trigger the immune response. If successful, subsequent trials will test its effectiveness.

In his video series An introduction to infectious diseases, Dr Barry Fox, a clinical professor of infectious diseases at the University of Wisconsin School of Medicine and Public Health, explained the history of anti-HIV drugs.


While an HIV vaccine would be a major step in the fight against HIV and AIDS, it is not the first drug treatment for HIV in general. Treatment for HIV started surprisingly before most people even knew what HIV was.

“The first drug breakthrough came when Jerome Horwitz, a scientist studying cancer, developed Zidovudine, also known as AZT,” said Dr Fox. “In 1964 it was originally designed for use as a cancer medicine, but it was unsuccessful. Twenty-five years later, other scientists surprisingly discovered that he had antiretroviral activity, and he became the first [antiretroviral therapy] Medication.

“It was the first treatment to give hope to HIV-positive patients.

HIV is a retrovirus, which means that its genetic material is RNA instead of DNA.

Dr Fox said he participated as a physician in the first nationally sponsored drug trials for AZT in the 1980s, where it was compared to a placebo. Patients set their watches in the middle of the night to take their medication every four hours.

“Although AZT was shown to be effective, it only made a small dent in a patient’s viral load in the blood,” he said. “It reduced the viral load by a logarithm, say, from one million to 100,000 virus particles. In addition, when used alone, resistance has developed rapidly.

AZT had significant side effects, especially nausea, Dr Fox said. However, due to the crisis presented by the HIV / AIDS pandemic, AZT was approved in 20 months instead of the usual eight to 10 years.

HIV viruses replicate between one and 10 billion per day, which means a high probability of mutation. For this reason aggressive pharmaceutical development is a necessity. Moderna’s HIV vaccine could one day play a major role in this endeavor.

Edited by Angela Shoemaker, The Great Courses Daily


Comments are closed.