An immunotherapy cocktail could aid relapsed mesothelioma patients without surgical options, according to a recent study.
A team of Italian researchers reported that a combination of two immunotherapy drugs improved long-term survival for patients whose mesothelioma had returned and was now inoperable.
The team — which included researchers from the University Hospital of Sienna and one from the SDN Institute in Naples — published their findings April 9 in The Lancet: Respiratory Medicine.
The open-label trial was a follow-up to earlier research published in 2018. Both Phase II studies relied on combining tremelimumab, an antibody-based drug still in clinical trials, with durvalumab, an antibody-based cancer drug that goes by the brand name Imfinzi.
Both drugs are immune checkpoint inhibitors, meaning they suppress proteins that are fooled into thinking cancer cells are healthy tissue, thereby allowing the body’s natural defenses to attack the cancer.
The follow-up study focused on 17 of the original 40 trial participants whose mesothelioma had returned and could not be surgically excised. Participants received a cocktail of the two checkpoint inhibitor drugs on a monthly basis for four months, with continued treatment of just durvalumab for an additional nine months.
The researchers found that 41 percent of the participants achieved “immune-related stable disease,” meaning the patients’ drug-empowered immune systems were holding the mesothelioma at bay. Nearly a quarter of patients — 23.5 percent — survived two years following the treatment, the team reported. More than half of them — 52.9 percent — lived at least a year.
An analysis conducted after the study was over found that the mesothelioma patients whose tumors had mutated as a result of the treatment had a slightly higher overall survival rate than those whose tumor cells showed less mutation. However, the team noted that the difference was not statistically significant.
No Severe Reactions
No immune-related objective responses were seen in the 17 patients that underwent retreatment, and no severe or life-threatening adverse events were reported during the study.
Given these results, the research team concluded that “tremelimumab combined with durvalumab was associated with long-term survival in patients,” and that retreatment with the immunotherapy cocktail is safe and produces “clinically meaningful outcomes.”