Immunotherapy may become a viable option for patients with cancer infected with HIV.
Researchers at Georgetown Lombardi Comprehensive Cancer Center recently examined whether immune checkpoint inhibitor (ICI) therapy is safe and effective in patients with advanced cancer who also live with HIV.
Among non-AIDS-defining illnesses, cancer is the leading cause of death in patients with HIV, with many of those affected at an increased risk during their lifetime. ICI therapy offers a new way to treat cancer, yet clinical trials have often excluded those with HIV due to concerns that it may have negative effects, such as virus reactivation.
The study, published in JAMA Oncology, focused on 73 patients with HIV found through medical literature whose cancer had been treated with ICI therapy. Many of the patients studied were found through reports and case series from oncologists who chose to treat their patients with cancer and HIV infection with the new cancer drugs.
The researchers found that patients with HIV did not experience increased adverse effects and HIV remained undetectable in 26 of the 28 (93%) with viral load before treatment.
“We hope our finding[s] will lead to increased study of checkpoint inhibitors in patients with HIV and cancer,” lead study investigator Chul Kim, MD, MPH, said in a press release. He explained that the checkpoint inhibitors may not only treat the cancer, but may also restore an “immune response against HIV in patients whose immune system is exhausted by its long fight with HIV.”
According to the American Cancer Society, immune checkpoint inhibitor therapy acts as an “off switch” for the proteins that cancer cells use to avoid being attacked by the body’s natural immune response. Antiretroviral drugs target and block different stages of the virus' life cycle, preventing it from replicating.
Kim and his co-author, Michael Cook, MD, also found that checkpoint inhibitors offered objective response rates in treating non-small cell lung cancer and melanoma that were similar to non-infected patients. The treatment also showed a benefit in those with Kaposi sarcoma, a cancer linked to HIV infection that has very little treatment options. The objective response in this patient population was 67%, according to the press release.
“And we found something that is really intriguing,” Kim added. “In 6 patients who had a detectable load of HIV in the blood before treatment, 5 had a decrease in their viral load after treatment. It could be that checkpoint inhibitors are helping to suppress HIV, though this finding needs to be verified in future studies.”
To further investigate these findings, Georgetown will soon launch a clinical trial to test ICI therapy as a first-line therapy in patients with lung cancer who have HIV or viral hepatitis.