MaaT Pharma announced that the DSMB unanimously recommended that the open-label, single arm pivotal Phase 3 clinical trial evaluating MaaT013 in acute Graft-versus-Host Disease (aGvHD), named ARES, continues without modification. The Overall Response Rate (ORR) was superior to pre-defined protocol assumptions. Therefore, the DSMB concluded that the benefit/risk ratio with ?high efficacy and low toxicity?

was favorable in this patient population. The DSMB is responsible for assessing the benefit/risk ratio with a particular focus on safety that is continuously reviewed throughout the course of the study. As per protocol, the DSMB met to review a specific safety and efficacy data analysis at Day 28, after inclusion of 30 patients.

The recruitment of patients in the ARES trial has continued while the DSMB reviewed the data. The conclusions of the DSMB review are as follow: Safety validation: No safety concerns were identified to date, based on the data from 30 patients reviewed. MaaT013 was well-tolerated, and the adverse event profile was consistent with the previously observed safety profile of MaaT013 (170+ patients treated to date within Phase 2 study and in the ongoing Early Access Program) and with patients with aGvHD, in general.

In addition, infections were specifically monitored and the DSMB concluded that no increased infectious risk was observed, and no fatal events were attributed to MaaT013. Efficacy assessment: The efficacy profile of MaaT013 was seen by the independent group of experts to be higher than expected in the protocol assumptions, signaling potential benefits for treatment-refractory aGvHD patients. The results from this prospective pivotal clinical trial confirm and strengthen previous results in a comparable patient population in the Early Access Program of MaaT013.

Positive benefit/risk ratio: The DSMB's comprehensive evaluation concluded that the benefit/risk ratio in the Phase 3 trial was favorable with ?high efficacy and low toxicity?. Next milestones for the ARES Phase 3 trial include: Mid-2024, primary endpoint evaluation: Gastrointestinal Overall Response Rate (GI-ORR) at day 28 Mid-2025, secondary endpoint evaluation: One-year Overall Survival As a reminder, ARES is a pivotal Phase 3 multicenter, international, open-label, single-arm study assessing the safety and efficacy of MaaT013 in 75 patients with Grade II-IV GI-aGvHD who are refractory to steroids and are resistant or are intolerant to ruxolitinib.