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Priothera Receives FDA clearance of Investigational New Drug (IND) to start Phase 2b/3 study with mocravimod in Acute Myeloid Leukemia (AML) Patients Undergoing Allogeneic Hematopoietic Stem Cell Transplant (HSCT)

Global Phase 2b/3 trial (MO-TRANS) assessing the efficacy and safety of mocravimod, a novel S1P receptor modulator, as an adjunctive and maintenance therapy in AML patients undergoing allogeneic HSCT, planned to start in H2 2022

Dublin, Ireland – 31st May 2022 – Priothera, a late-clinical stage biotechnology company pioneering the development of its S1P receptor modulator compound, mocravimod, today announces that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation (FTD) for mocravimod in combination with allogeneic Hematopoietic Stem Cell Transplant (HSCT) for post remission therapy of Acute Myeloid Leukemia (AML) patients. FDA’s Fast Track designation is designed to facilitate the development and expedite the review of new drugs that are intended to treat serious or life-threatening diseases and that demonstrate the potential to address unmet medical needs.

Priothera is working to initiate the MO-TRANS global Phase 2b/3 study in Europe, US and Japan, to assess the efficacy and safety of mocravimod as an adjunctive and maintenance therapy in adult AML patients undergoing allogeneic HSCT. The MO-TRANS study is expected to start in the second half of 2022 and preliminary data from this study are expected by the end of 2024.

Karen Von Graevenitz, Head of Regulatory Affair at Priothera, commented ““The Fast Track designation grant for mocravimod in combination with allogeneic HSCT is an important milestoneand underlines the significant unmet need in AML patients undergoing HSCT, a serious disease where currently no available therapy exists. The designation means mocravimod will be eligible for expedited review and we will work closely with the US FDA to advance the global Phase 2/3 trial which is due to start in the second half of 2022.”

Florent Gros, Co-Founder and CEO of Priothera, added: “Following being granted orphan drug designations for mocravimod in the US and Europe, we are pleased to have been granted Fast Track designation for this highly promising compound. This important regulatory milestone moves us a step closer to bringing mocravimod to patients with AML and other hematologic malignancies.”

About Mocravimod

Mocravimod (also known as KRP203), is a synthetic, sphingosine 1-phosphate receptor (S1PR) modulator. This novel investigational drug has been assessed in Phase 1 and Phase 2 trials for safety and tolerability, as well as for efficacy in several autoimmune indications. Promising data from a Phase 1b/2a clinical study in patients with hematological malignancies led Priothera to further develop mocravimod for the treatment of blood cancers.

Mocravimod will be investigated as an adjunctive and maintenance treatment in a Phase 2b/3 study as a potential treatment for patients with Acute Myeloid Leukemia (AML) receiving allogeneic hematopoietic stem cell transplantation (HSCT). Allogeneic HSCT is the only potentially curative approach for AML patients, but current treatments have unacceptably high mortality and morbidity rates.

Priothera leverages S1PR modulator’s unique mode of action to maintain anti-leukemia activity – graft-versus leukemia (GVL) while reducing tissue damage resulting from graft-versus-host disease (GVHD), a consequence of allogeneic HSCT. This novel treatment approach – mocravimod being the only S1PR modulator treating blood cancers – tackles a high unmet medical need and intends to add quality life to patients.

About Priothera

Priothera is leading the way in developing orally applied sphingosine–1–phosphate (S1P) receptor modulators for the treatment of hematological malignancies. S1P receptor modulators are known to largely reduce egress of T cells from lymphatic tissues. Not being an immunosuppressant, mocravimod maintains the graft-versus-leukemia (GVL) benefits in patients receiving HSCT while inhibiting graft-versus-host-disease (GVHD).

Priothera was founded in 2020 by an experienced team of drug development experts and is headquartered in Dublin, Ireland, and with a subsidiary in Saint-Louis, France. The Company is backed by international founding investors Fountain Healthcare Partners (Dublin, Ireland), funds managed by Tekla Capital Management, LLC (Boston, Massachusetts), HealthCap (Stockholm, Sweden) and EarlyBird Venture Capital (Berlin, Germany).

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Florent Gros, CEO

MEDiSTRAVA Consulting
Sylvie Berrebi, Sandi Greenwood, Frazer Hall
T: +44 (0) 203 928 6900

Source: Priothera