MaaT, eyeing 2026 launch for microbiome therapy, posts 18-month data in aGvHD

A year after a long-running clinical hold was lifted on MaaT Pharma’s pooled fecal therapy, the microbiome biotech has touted 18-month data as proof it’s on track to launch the drug in acute graft-versus-host disease (aGvHD) in two years’ time.

The 18-month data are taken from 140 patients with either steroid-refractory or steroid-dependent gastrointestinal aGvHD who received the therapy, dubbed MaaT013, as part of the French biotech’s Pharma Early Access Program. Among these heavily pretreated patients, the data showed a “clear overall survival advantage,” with a 54% rate of overall survival at six months, 47% at 12 months and 42% at 18 months.

Overall survival was “significantly higher” in patients who responded to MaaT013 compared to non-responders at 18 months—at 58% versus 24%, respectively—the company noted.

The biotech also drilled down into a subset of 49 patients whose disease had proven resistant to treatment by both steroids and Incyte’s Jakafi. Among these patients—who more closely match those in an ongoing phase 3 trial of MaaT013—the gastrointestinal overall response rate was higher, at 63%, than the 52% across the whole group. Overall survival at 18 months remained at 42% among this subset.

“The confirmation of an improvement in 18-month survival, compared to the data already presented, by the company, at 12 months, reinforces our confidence in the ongoing development, notably the results of the current phase 3 trial,” MaaT’s CEO Hervé Affagard said in a statement.

“Beyond the significant impact for patients, this advancement distinguishes our treatment in a context where current options offer only limited benefits and lead to severe complications,” Affagard added. “Anticipating a positive phase 3 outcome and a potential commercial launch in 2026, we aim to capture a substantial share of the market for third-line patients, thereby marking a turning point in the management of this condition.”

MaaT has seen combining stool samples from multiple donors as a way to improve the diversity and standardization of MaaT013. But the practice proved to be a sticking point in the U.S., where the FDA imposed a 20-month hold on moving the drug into a phase 3 for aGvHD that was only lifted in April 2023.

As well as the phase 3 study of MaaT013 in aGvHD, the biotech is also testing the therapy for metastatic melanoma in a phase 2 study in combination with immune checkpoint inhibitors.

The company’s other clinical-stage asset is MaaT033, another so-called “microbiome ecosystem therapy” that is in a phase 1 trial for amyotrophic lateral sclerosis and a phase 2 study for improving survival among blood cancer patients who have received a bone marrow transplant.