A functional cure for HIV is the goal of Addimmune, a new spinoff company of Rockville-based biotech American Gene Technologies (AGT).
“Think about how that’s a dream come true for nearly 40 million people in the world and 1.2 million people in the United States,” says Jeff Galvin, AGT’s CEO and the expected future CEO of Addimmune, in reference to statistics from, respectively, the World Health Organization and the Centers for Disease Control and Prevention. The National Institutes of Health defines a functional cure in this case as “the long-term control of HIV replication without treatment.”
AGT has spent the last 15 years developing gene and cell therapies and running programs for immuno-oncology and a cure for phenylketonuria, an inherited metabolic disorder. Addimmune was launched in June after AGT’s successful—if small—Phase 1 clinical trial of its single-infusion HIV gene therapy, AGT103-T. Creating Addimmune as a spinoff allows the company to accelerate research and focus resources on future clinical trials, Galvin says.
There are thousands of people in Addimmune’s backyard hoping for a cure. In Montgomery County, more than 3,600 people were living with HIV at the end of 2021, according to the Maryland Department of Health.
Melvin Cauthen, the administrator for HIV/STI services at Montgomery County’s Department of Health and Human Services, says funding from a federal initiative, Ending the HIV Epidemic, has helped the county address the health issue. The county is working on making its clinics and services visible and accessible to those in need of care.
Cauthen says that when it comes to the research and development of treatments and cures for HIV, county officials keep an eye on the latest news but ultimately look to the CDC for guidance.
“Right now, we’re focused on making sure that [people living with HIV] are healthy while the folks who are working in the labs are coming up with hopefully what will be a cure,” Cauthen says.
Results from AGT’s Phase 1 trial were published in November 2022 in Frontiers in Medicine, a peer-reviewed scientific journal for medical advancement. Thirteen participants with HIV were enrolled in the trial.
Published results from the Phase 1 trial show no serious adverse events were observed among participants and 100% of participants demonstrated an active immune response to HIV, even after they stopped taking HIV treatment (antiretroviral therapy).
According to Addimmune, its gene and cell therapy modifies the genes of HIV-infected CD4 T cells to prevent HIV infection, reduce depletion of the CD4 cells and prevent infected cells from releasing new HIV virus particles. Per the National Institutes of Health, CD4 T cells coordinate the body’s immune response but HIV destroys CD4 cells, thus weakening the immune system.
Galvin explains that scientists use a lentivirus—an RNA virus commonly used in gene therapy—to modify the CD4 cell by stripping a receptor off the cell’s surface that HIV uses as a door handle to get inside.
According to Galvin, there is a long path ahead as its work moves through the regulatory process to prove to the Food and Drug Administration that the therapy is safe and effective.
This year, AGT submitted the final report of the Phase 1 trial to the FDA and is now concentrating on the next steps toward a Phase 2 clinical trial, which is expected to begin in late 2024 to early 2025, according to a spokesperson for Addimmune. The Phase 2 trial will seek to further evaluate the potential effects of AGT103-T on immune response in a larger patient population.
Since the regulatory process can take years, a spokesperson for Addimmune was hesitant to put a deadline on when a cure might be available, but says in a statement, “Our team of dedicated scientists and researchers is diligently working on this critical challenge.”
This story appears in the November/December issue of Bethesda Magazine.