Researchers tested whether immunotherapy could be safely used in HIV-positive patients with cancer.
Treating cancer patients who are HIV-positive with immunotherapy agents is safe and feasible, according to a new study. CD4 lymphocyte count and HIV viral load should be monitored during treatment, but anti–programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors should not be ruled out because of HIV positivity.
“[Patients with HIV] are at higher risk for a number of cancers: AIDS-defining forms, the diagnosis of which results in the categorization of a person as suffering from AIDS, but also various other types that they are two to three times more likely to develop than in the general population, such as anal, skin, head and neck, and lung cancer,” said Aurélien Gobert, MD, of Groupe Hospitalier Pitié Salpêtrière in Paris, according to a press release. HIV-positive patients are generally excluded from clinical trials, given the assumption that they are at higher risk of developing complications, so immunotherapy’s efficacy and safety in this population was unknown.
The researchers evaluated immunotherapy in 20 HIV-positive patients; one had metastatic melanoma, while the other 19 had metastatic non–small-cell lung cancer. The results were presented at the European Society for Medical Oncology (ESMO) 2018 Congress, held October 19–23 in Munich.
At the time of diagnosis, the median lymphocyte count in the cohort was 338.5/mm3. The viral load was undetectable in 17 patients, and it was low in 2 cases and unknown in 1 patient. The patients were followed for a median of 11 months, and all patients were treated with nivolumab for a median of 6 infusions.
There were no toxic deaths reported, and no immune-related adverse events. One patient had a rising HIV viral load and decreasing CD4 lymphocyte count, indicating that the virus was reactivated. However, this occurred after an interruption to antiretroviral therapy.
Response to nivolumab was assessable in 17 of the patients. Among those patients, there were 4 partial responses (24%), 2 patients had stable disease (12%), and the remaining 11 patients had progressive disease (64%). Gobert stressed that the size of this cohort and the length of follow-up does not allow firm conclusions on efficacy.
“Our key insight then, is that the treatment appears to be well tolerated by HIV-positive cancer patients-so long as antiretroviral therapy is continued in parallel,” Gobert said.
John Haanen, PhD, of the Netherlands Cancer Institute, commented on the study, and he noted that in spite of its small size it is among the largest so far conducted on HIV patients treated with immunotherapy. “The results confirm those of other, smaller cohorts in showing that while on antiretroviral therapy, cancer patients living with HIV can safely receive anti–PD-1 treatment,” he said. “The efficacy data also suggest that the overall response rate of HIV-positive patients seems to be similar to that of other cancer patients. These promising results need to be confirmed in larger studies-ideally, in a prospective clinical trial.”