Larimar Therapeutics, Inc. announced dosing of the first patient in an open label extension (OLE) study evaluating 25 mg daily subcutaneous injections of nomlabofusp in participants with Friedreich's ataxia (FA). Nomlabofusp (CTI-1601) is a novel protein replacement therapy designed to address the root cause of Friedreich's ataxIA (FA) by delivering frataxin to mitochondria. Importantly, the OLE study will inform on the long-term safety profile and tissue frataxin levels and provide a first look at real-life experience with self-administration by patients or administration by a caregiver.

Participants who completed treatment in the recent Phase 2 dose exploration trial, or who previously completed a prior Phase 1 clinical trial of nomlabofusp are potentially eligible to screen for the OLE. Clinical measures collected during the trial will be compared to data from a synthetic control arm derived from participants in the Friedreich's Ataxia Clinical Outcome Measures Study (FACOMS) database. To escalate the dose in the OLE study, data from the 50 mg cohort of the Phase 2 dose exploration study, as well as available data from the 25 mg dose in the OLE study., will be submitted for FDA review due to the continued partial clinical hold.

Initial data from the OLE study is expected in fourth quarter 2024. Nomlabofusp is a recombinant fusion protein intended to deliver human frataxin to the mitochondria of patients with Friedreich's atAXia who are unable to produce enough of this essential protein. Nomlabofusp has been granted Rare Pediatric Disease designation, Fast Track designation and Orphan Drug designation by the U.S. Food and Drug Administration (FDA), Orphan Drug Designation by the European Commission, and a PRIME designation by the European Medicines Agency.