Progress in Fight against HIV as Vaccine Heads to Clinical Trials

mrna vaccine developed by moderna is first of its kind for HIV

By Jonny Lupsha, Wondrium Staff Writer

Human trials will soon begin for an HIV vaccine made by Moderna. The treatment is an mRNA vaccine, meaning it teaches the body to trigger an immune response to certain proteins. It’s the largest drug breakthrough for HIV to date.

Scientist looking through microscope researching HIV vaccines
The HIV virus is a retrovirus since its genetic material is RNA instead of DNA, which means scientists are now focusing on developing a mRNA vaccine for it. Photo By Rapeepat Pornsipak / Shutterstock

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

The injection gives the body instructions 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 recognizes it quickly and neutralizes it. The Phase 1 trials only aim to determine if the vaccine will trigger the immune response. If successful, later trials will test its effectiveness.

In his video series An Introduction to Infectious Diseases, Dr. Barry Fox, Clinical Professor of Infectious Disease at the University of Wisconsin School of Medicine and Public Health, explained the history of HIV drugs.


While an HIV vaccine would be a major step in the fight against HIV and AIDS, it’s hardly the first drug treatment for HIV in general. Treating HIV got off to a surprising start—even before most people knew what HIV was.

The first drug breakthrough came when Jerome Horwitz, a scientist studying cancer, developed Zidovudine, also known as AZT,” Dr. Fox said. “In 1964, it was originally designed to be used as a cancer drug, but it was a failure. Twenty-five years later it was surprisingly found by other scientists to have anti-retroviral activity, and it became the first [antiretroviral therapy] medicine.

“This was the first treatment to give hope to HIV patients.”

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

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

“While AZT was found to be effective, it only made a small dent in a patient’s viral burden in the blood,” he said. “This reduced the viral load by one logarithm, for example, from one million down to 100,000 virus particles. Also, when used alone, resistance rapidly developed.”

AZT did have significant side effects—especially nausea, Dr. Fox said. However, due to the crisis that the HIV/AIDS pandemic presented, AZT was approved within 20 months instead of the usual eight to 10 years.

HIV viruses replicate in the range of one to 10 billion per day, meaning a high likelihood of mutation. Because of this, aggressive pharmaceutical development is a necessity. Moderna’s HIV vaccine may one day play a major role in this endeavor.

Edited by Angela Shoemaker, Wondrium Daily