Lupin Limited (Lupin) and Exeltis Healthcare S.L (Exeltis) announced that the Spanish Ministry of Health (MSCBC) has approved the reimbursement of Lupin's NaMuscla® (mexiletine) for the symptomatic treatment of myotonia in adults with non-dystrophic myotonic (NDM) disorders on the National Health and Pharmacy Service. NaMuscla® is the first and only licensed product for this indication in Europe and will be commercialized by Lupin's partner Exeltis in Spain. NDM disorders are a group of rare, inherited neuromuscular disorders with an estimated prevalence of 1 case per 100,000 inhabitants in Spain, and is characterized by the inability to relax muscles following voluntary contraction (myotonia).

NaMuscla® reduces myotonia symptoms in people with NDM, resulting in a significant improvement in quality of life and other functional and clinical outcomes for patients. NaMuscla®, which has been designated orphan drug status, received EU marketing authorization in December 2018. To date, people in Spain living with NDM have had limited access to a licensed treatment for myotonia that can reduce the daily burden of this disabling, lifelong condition.

Limited access leads to inconsistent medication supply, administrative challenges, and associated financial burdens. This, alongside limited clinical experience among healthcare professionals due to the rare nature of the disease, may result in significant harm to patients. Lupin's pediatric trial (NCT04624750), part of the pediatric investigation plan for NaMuscla® in children with myotonic disorders, is ongoing and successfully concluded patient enrolment in a first patient cohort group who were offered and rolled over into a 2-year follow-up study (NCT04622553).

A post-authorization study to address long-term safety and treatment effects of NaMuscla® on patient-reported outcomes in adults with NDM (NCT04616807) has concluded patient enrollment and will provide 3 years prospective data on NaMuscla® in a real-life setting.