Novel Cell Therapy Shows Promise for Pearson Syndrome in Phase 2 Trial’s Initial Enrollees

An ongoing phase 2 trial of the first-in-class cell therapy MNV-201 for Pearson syndrome shows favorable interim efficacy and safety data. Minovia Therapeutics Ltd., the Haifa, Israel-based biotechnology company developing MNV-201, announced the data in a press release.

Pearson syndrome is a rare but life-threatening mitochondrial disease in pediatric patients for which there are currently no FDA-approved therapies. It is caused by mitochondrial DNA deletions, which lead to failure to thrive in patients and produce serious clinical conditions such as sideroblastic anemia, metabolic crisis, organ dysfunction, and bone marrow failure.

MNV-201, the lead investigational compound under development at Minovia, is based on the company’s proprietary Mitochondrial Augmentation Technology (MAT). This mechanism of action of the cell therapy directly acts against the syndrome’s etiology by inserting healthy mitochondria into the patient’s stem cells. MNV-201 is also currently under clinical evaluation for use in myelodysplastic syndromes.

The current phase 2 trial of MNV-201 for Pearson syndrome plans to enroll six patients. The newly reported interim data come from the first three enrollees of the trial, along with two compassionate use patients with Kearns-Sayre syndrome (KSS). Researchers presented these early results at the 2025 annual meeting of the United Mitochondrial Disease Foundation, held in June in St. Louis, Missouri.

“These Phase 2 data show extremely encouraging results, even in such a small patient sample,” commented Minovia co-founder and chief executive officer, Natalie Yivgi-Ohana, PhD. “MAT’s unique mechanism of action provides a novel approach to addressing these devastating mitochondrial deletion syndromes.”

To measure the preliminary efficacy of MNV-201 in this trial, investigators determined a novel endpoint for use in the trial based on findings from a prior natural history study conducted at the Children’s Hospital of Philadelphia. At six months of follow-up of the trial, two of the three enrollees exhibited growth improvement as compared with pre-treatment and better quality of life scores.

Safety profile findings, thus far, from the trial have also been positive, and MNV-201 is meeting the trial’s primary endpoint. Patients have not had any treatment-related serious adverse events, and most adverse events that occurred dissipated within four days and were attributed to the pre-treatment apheresis procedure. Moreover, no anti-mitochondrial antibodies have been detected in the patients.

The two patients with KSS who received MNV-201 in the trial via compassionate use, too, demonstrated improved quality of life scores and a favorable safety profile on the cell therapy. Minovia considers these initial results to all be supportive of continuation of the trial, which the company projects will finish before the end of 2025.

“The clinical experience from our first-generation product helped identify a novel primary endpoint for this heterogenic group of patients and resulted in positive interactions with the FDA that could be leveraged towards MNV-201 development, enabling the current clinical trial,” Dr. Yivgi-Ohana remarked.

MNV-201 already has Fast Track Designation and Rare Pediatric Disease Designation from the FDA. At this time, Minovia is coordinating with the FDA on the design of a pivotal trial for the agent, with registrational studies to be launched in 2026.