MaaT Pharma

Regulatory Filings • Apr 11, 2023

MaaT Pharma to Present Clinical Data for MaaT013 and MaaT033 at 49th EBMT Annual Meeting

• Data, which were previously presented at the American Society of Hematology (ASH) Annual Meeting in December 2022, includes results of 81 patients with gastrointestinal acute Graft-versus-Host Disease (GI-aGvHD) treated with MaaT013 as part of a compassionate use program in France, and results of the Phase 1b CIMON trial with the Company's Microbiome Ecosystem TherapyTM (MET) oral capsule MaaT033 in acute myeloid leukemia (AML) patients.
• The Company was selected for two oral presentations at the conference; presentations will highlight MaaT013 and MaaT033's potential to improve survival outcome for patients with hematological malignancies.

Lyon, France, April 11th , 2023 – 6:00 pm CET - MaaT Pharma (EURONEXT: MAAT – the "Company"), a French clinical-stage biotech and a pioneer in the development of Microbiome Ecosystem TherapiesTM (MET) dedicated to improving survival outcomes for patients with cancer, announced that promising clinical data for its drug candidates, MaaT013 and MaaT033 will be reported in two oral presentations by Pr. Florent Malard, Professor of Hematology at the Saint-Antoine Hospital and Sorbonne University during the 49th Annual Meeting of the European Society for Blood and Marrow Transplantation (EBMT 2023) to be held as an hybrid event in Paris, France, from April 23 - 26, 2023. The EBMT Annual Meeting is a leading event in Europe that focuses on cutting-edge scientific content related to transplantation and cellular therapy. The oral presentations will include data that were previously presented at the American Society of Hematology conference in December 2022.

Key clinical findings with MaaT013 as compassionate use in France (Early Access Program or "EAP") in 81 patients

• Clinical results showed a GI-Overall Response Rate (ORR) of 56% including 30 complete responses (37%), 11 very good partial responses (14%) and 4 partial responses (5%) in GIaGvHD patients 28 days after treatment initiation; 12-month overall survival was 59% in patients responding to MaaT013 treatment.
• A 65% ORR was observed in 31 patients treated with MaaT013 as 3rd -line therapy after failure to 2nd -line ruxolitinib treatment; 12-month overall survival in this group responding to

MaaT013 treatment was 74%; similar patient population is being treated in MaaT Pharma's ongoing pivotal Phase 3 ARES clinical trial in Europe.

Oral Presentation details for MaaT013:

Title: Pooled Fecal Allogenic Microbiotherapy for Refractory Gastrointestinal Acute Graftversus Host Disease: Results from the Early Access Program in France Abstract number: OS05-08 Session Name: Oral Session 5 | GVHD (Clinical) Date/Time: Wednesday, April 26, 2023 11:33 am - 11:42 am CET Location: Amphithéâtre Bleu

Key clinical findings with MaaT033 in Phase 1b study CIMON

• MaaT033 was shown to be safe and tolerable in 21 patients; 4 severe adverse events were reported in 4 patients, only one was considered as possibly related to the treatment by the investigator.
• Treatment with MaaT033 induced increased microbiota richness as well as strong and persistent engraftment in cohorts 3 and 4 of the dose escalation study, which consisted of taking 3 capsules of the drug candidate per day.
• Engraftment following MaaT033 treatment correlated with increased anti-inflammatory marker levels and reduced inflammatory marker levels in patients.
• MaaT Pharma is preparing a randomized, double-blind, placebo-controlled pivotal Phase 2b clinical trial for MaaT033; trial start is expected in Q2 2023 as previously announced.

Oral Presentation details for MaaT033:

Title: Restoration of Gut Microbiota Diversity with Oral Pooled Fecal Microbiotherapy in Acute Myeloid Leukemia Patients after Intensive Chemotherapy: the Phase 1b CIMON trial Abstract number: OS06-08 Session Name: Oral Session 6 | Acute Leukemia (II) Date/Time: Wednesday, April 26, 2023 10:39 am - 10:48 am CET Location: Maillot

Participants are also invited to meet with MaaT Pharma's clinical team at booth #48. All EBMT sessions that take place onsite will be live-streamed through the congress platform and will be available on-demand after they are aired live.

Link to register: https://eu.eventscloud.com/ebmt23

About MaaT Pharma

MaaT Pharma, a clinical stage biotechnology company, has established a complete approach to restoring patient-microbiome symbiosis in oncology. Committed to treating cancer and graft-versushost disease (GvHD), a serious complication of allogeneic stem cell transplantation, MaaT Pharma has launched, in March 2022 in Europe, a Phase 3 clinical trial for patients with acute GvHD, following the achievement of its proof of concept in a Phase 2 trial. Its powerful discovery and analysis platform, gutPrint®, supports the development and expansion of its pipeline by determining novel disease targets, evaluating drug candidates, and identifying biomarkers for microbiome-related conditions. The company's Microbiome Ecosystem Therapies are produced through a standardized cGMP manufacturing and quality control process to safely deliver the full diversity of the microbiome, in liquid and oral formulations. MaaT Pharma benefits from the commitment of world-leading scientists and established relationships with regulators to support the integration of the use of microbiome therapies in clinical practice.

MaaT Pharma is the first company developing microbiome-based therapies listed on Euronext Paris (ticker: MAAT).

Forward-looking statements

This press release contains forward-looking statements. All statements other than statements of historical fact included in this press release regarding future events are subject to (i) change without notice and (ii) factors beyond the Company's control. These statements may include, but are not limited to, statements preceded by, followed by or including words such as "target", "believe", "expect", "aim", "intend", "may", "forecast", "estimate", "plan", "project", "will", "may have", "likely", "should", "expect" and other words and terms of similar meaning or the negative thereof. Forward-looking statements are subject to inherent risks and uncertainties beyond the Company's control that could cause the Company's actual results or performance to differ materially from those expressed or implied by such forward-looking statements.

MaaT Pharma – Investor Relations

Hervé AFFAGARD Co-founder and CEO Siân CROUZET COO / CFO +33 4 28 29 14 00 invest@maat-pharma.com MaaT Pharma – Media Relations Pauline RICHAUD Senior PR & Corporate Communications Manager +33 6 14 06 45 92 prichaud@maat-pharma.com

Trophic Communications Corporate and Medical Communications Stephanie MAY or Charlotte SPITZ +49 171 351 2733 maat@trophic.eu