Study Examines Safety of Microbiome Transplants Prior to Immunotherapy

Fecal microbiome transplants (FMTs) from healthy donors in conjunction with anti-PD-1 immunotherapy is safe among patients with advanced melanoma, researchers from Western University in Ontario and elsewhere report. FMTs have been suggested as a way to boost cancer patients' response to immunotherapy treatment. In this Phase I study assessing safety, the researchers treated 20 patients with unresectable or metastatic cutaneous melanoma with FMT before then treating them with either nivolumab or pembrolizumab. As they report in Nature Medicine, the researchers found the approach to be safe, with no patients experiencing grade 3 adverse events from FMT alone, though five patients did have grade 3 immune-related adverse events. In addition to the safety data, the researchers report that the objective response rate was 65 percent and the complete response rate was 20 percent. "The connection between the microbiome, the immune system, and cancer treatment is a growing field in science," senior author Saman Maleki from Lawson Health Research Institute and Western University says in a statement. "This study aimed to harness microbes to improve outcomes for patients with melanoma."