ASH 2023: microbiome-based therapy shows potential in graft-versus-host disease

Results from MaaT Pharma’s Early Access Program (EAP) for its microbiome-based therapy MaaT013, have demonstrated positive overall response and overall survival rates in European patients with graft-versus-host disease (GvHD).

The findings were presented at the 2023 American Society of Hematology (ASH) Annual Meeting.

MaaT013 is an off-the-shelf, pooled-donor, enema Microbiome Ecosystem Therapy^TM.

Summary of key results

According to MaaT Pharma, there were 111 patients with steroid-refractory (SR) or steroid-dependent (SD) gastrointestinal acute graft-versus-host disease (GI-aGvHD) who were given MaaT013.

Gastrointestinal overall response rate (GI-ORR) of 53 percent was observed at day 28. For the patients treated with the microbiome therapeutic, overall survival was 81 percent for responders and eight percent for non-responders, in population matching patients in the ongoing Phase III ARES clinical trial.

At six months, overall survival was 56 percent. At 12 months, this rate was 47 percent at 12 months with a median follow up of 355 days.

Overall survival was significantly higher in patients who responded to MaaT013 compared to non-responders (67 percent versus 24 percent at 12 months).

Additionally, a subgroup of 38 patients with similar treatment sequence to the Phase III ARES clinical trial, included patients previously treated with steroids and ruxolitinib. GI-ORR was observed 61 percent at day 28.

Overall response was found to be 54 percent. Complete response was observed in 51 percent of these patients. Overall survival in this group was 55 percent at six months and 52 percent at 12 months.

Harnessing the potential of microbiome therapeutics

“GvHD remains a significant challenge and source of mortality following allogeneic hematopoietic stem cell transplantation (HSCT),” stated Professor Mohamad Mohty, Professor of Hematology at Sorbonne University, and head of the Clinical Hematology and Cellular Therapy Department at Saint-Antoine Hospital, France. 

“The clear connection between treatment response and overall survival demonstrates microbiome therapies as a potentially life-saving approach, particularly in patients who have failed earlier treatment lines, corticosteroids and ruxolitinib,” added Professor Mohty.

An ongoing Phase III trial in Europe to confirm these results in ruxolitinib-refractory patients with overall response rate expected in the middle of 2024.