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Priothera announces first patients enrolled in pivotal MO-TRANS global Phase 2b/3 study with mocravimod as an adjunctive and maintenance therapy for patients with Acute Myeloid Leukemia (AML) undergoing allogeneic Hematopoietic Cell Transplant (HCT)

Mocravimod is the only S1PR modulator being developed to treat blood cancers and improve CAR-T therapy 

Phase 1b/2a data has shown mocravimod is safe and well tolerated

Dublin, Ireland – January 23, 2023 – Priothera, a late-clinical stage biotechnology company pioneering the development of its S1P receptor modulator compound mocravimod today announced that the first patients have been enrolled in the pivotal MO-TRANS global Phase 2b/3 study evaluating mocravimod in AML patients undergoing allogeneic hematopoietic cell transplant (HCT).

Mocravimod, a sphingosine 1 phosphate (S1P) receptor modulator which has been previously tested in multiple autoimmune indications, is being developed to enhance the curative potential of allogeneic HCT. Mocravimod has shown a clinically relevant benefit in an early clinical study in patients with hematologic malignancies undergoing allogeneic HCT.

Priothera is initiating the pivotal MO-TRANS global Phase 2b/3 study in Europe, Israel, the US and in additional Asian and Latin American countries, to assess the efficacy and safety of mocravimod as an adjunctive and maintenance therapy in AML patients undergoing allogeneic HCT. The double-blind, placebo-controlled study assesses relapse-free and overall survival of two dose levels of mocravimod in comparison to placebo. Topline data from this study are expected in 2025.

Marcos de Lima, M.D., is the Principal Investigator for the MO-TRANS global Phase 2b/3 trial. Dr. de Lima is professor of medicine at The Ohio State University College of Medicine and a hematologist-oncologist at The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute.

Prof de Lima saidWe are excited to be part of the important MO-TRANS global Phase 2b/3 study to investigate mocravimod, a potential new adjunctive and maintenance therapy for patients with Acute Myeloid Leukemia undergoing allogeneic Hematopoietic Cell Transplant. Maintenance therapy is fast becoming the new frontier in the treatment of AML and we are committed to bringing forth new innovative therapies to AML patients.”

Elisabeth Kueenburg, M.D., Chief Medical Officer at Priothera, commented: “This MO-TRANS global Phase 2b/3 study builds on pre-clinical and clinical proof of concept studies which demonstrated mocravimod’s ability to improve survival outcomes for patients with hematological malignancies requiring allogeneic HCT. The mode of action has been well-established in autoimmune indications, but never in hematology. Mocravimod has the potential to be a first-in-class therapy in maintaining the graft-versus-leukemia effect, while preventing graft-versus-host disease, one of the most serious complications of allogeneic HCT. We expect this trial to deliver important clinical data supporting the registration of mocravimod in this indication.

Florent Gros, Co-Founder and CEO of Priothera, said: “Having successfully enrolled the first AML patients undergoing allogeneic HCT in our MO-TRANS global study represents a significant milestone for Priothera as we believe mocravimod has the potential to address a significant unmet need. Furthermore, we anticipate a strong uptake in patient enrollment with a significant number of patients currently being identified. We look forward to seeing topline results in 2025.”  

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 and the improvement of CAR-T cell therapy.

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

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

About Priothera

Priothera is leading the way in developing orally applied sphingosine-1-phosphate (S1P) receptor modulators for the treatment of hematological malignancies and for the improvement of CAR-T cell therapies. S1P receptor modulators are known to largely reduce egress of T cells from lymphatic tissues. Unlike immunosuppressive drugs, mocravimod does not suppress the graft-versus-leukemia (GVL) benefits in patients receiving HCT 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), EarlyBird Venture Capital (Berlin, Germany), as well as non-dilutive financing in the form of loans from the European Investment Bank under its Venture Debt Instrument and Bpifrance (Grand Est Bpifrance) in the form of a R&D innovation loan.

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Florent Gros, CEO

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Source: Priothera