Combining the personalised cancer vaccine with adoptive T cell therapy (ACT) can benefit patients with late-stage, drug-resistant ovarian cancer, a new study has said.
According to the study published in Nature Cancer journal, combining the personalised cancer vaccine with ACT yielded control of the disease within three months in 12 of 17 patients and the treatment was also found to be safe and relatively well tolerated.
Researchers analysed responses to the combination therapy of 18 patients with advanced ovarian cancer who had previously participated in a clinical trial evaluating a therapeutic regimen that incorporated the personalised cancer vaccine developed by the institute itself.
During the study, patients were given an infusion of their own vaccine-primed, circulating immune cells (specifically, T cells), followed by multiple periodic doses of their personalised vaccines.
“This treatment could not eliminate tumours, but it did provide considerable benefit to many of the patients, who had all undergone extensive treatment prior to enrolling in the trial and were in the late stages of the disease,” said Lana Kandalaft, one of the researchers.
Ovarian cancer, like many other malignancies, has so far proved largely resistant to immunotherapies, most of which harness killer T cells, which destroy sick and infected cells. Ovarian cancer cells do, however, express neoantigens, which are randomly mutated proteins that can activate anti-tumor T cell responses, the study mentioned.
“We were very happy that we could demonstrate how the combination therapy improved anti-tumor immune responses, and that those changes correlated to patient benefit,” said Sara Bobisse, senior author of the study.
“Most notably, we could show that T cells targeting the neoantigens were reinvigorated by the combination therapy and correlated with positive responses to the therapy,” she added.
According to George Coukos, one of the authors of the study, this study illustrates how rational approaches to the design of immunotherapies can help overcome the barriers to immune responses that are erected by a variety of cancers, not least ovarian cancer.
