MaaT Pharma Faces CHMP Negative Trend Opinion on Xervyteg, Triggers Re-Examination Procedure

A "negative trend" opinion from EMA's CHMP on MaaT Pharma's Marketing Authorization Application for MaaT013 (Xervyteg®) signals a significant regulatory obstacle for microbiome-based therapies in Europe, with the formal vote expected at the June 2026 CHMP meeting and a re-examination procedure anticipated to follow.

The opinion emerged during the Oral Explanation phase, ahead of the committee's scheduled vote. Under EMA re-examination procedure, a sponsor may challenge a negative CHMP opinion by submitting new scientific arguments within a defined timeframe; the committee then convenes a re-examination group to assess the grounds. For regulatory affairs leads at companies pursuing novel biologic or microbiome product authorizations in the EU, the MaaT013 trajectory illustrates how pivotal trial data, even when presented at a presidential symposium, may not fully satisfy CHMP's benefit-risk threshold without supplementary argumentation.

MaaT Pharma presented final results from the ARES pivotal trial at the EBMT 2026 Annual Congress in March, alongside real-world data from the CHRONOS study (n=59), which recorded 29% 12-month overall survival and a 37% Day-28 GI-overall response rate in third-line steroid-refractory gastrointestinal aGvHD patients treated without microbiome-based therapy. Those CHRONOS figures were published in Bone Marrow Transplantation Journal in April 2026, and the company has cited them as evidence of unmet medical need in the indication.

Operationally, the company transitioned its Early Access Program to Clinigen in January 2026, reaching approximately 230 patients across 13 countries. Revenues of €0.8 million in Q1 2026 were derived entirely from that EAP. Cash and cash equivalents stood at €18.1 million as of March 31, 2026, with runway extended to November 2026 following drawdown of EIB Tranche B, a window the company has framed as sufficient to support the re-examination process.

For QA directors and regulatory leads monitoring EU microbiome therapy precedents, the re-examination outcome will carry weight beyond MaaT013: CHMP's final reasoning, once published, will inform how sponsors of other live biotherapeutic products structure their benefit-risk narratives and real-world evidence packages under the current EU marketing authorization framework.

The formal CHMP vote in June 2026 and MaaT Pharma's subsequent re-examination submission will set a measurable timeline for the first EU regulatory decision on a full-ecosystem microbiome therapy in the aGvHD setting.

Source: MaaT Pharma via corporate press release, May 26, 2026.