Myrtelle's investigational gene therapy, rAAV-Olig001-ASPA (MYR-101), has demonstrated promising results in a phase 1/2 clinical trial for Canavan disease (CD), showcasing significant reductions in the key biomarker N-Acetylaspartate (NAA) and improvements in brain structure and function. The data, presented by Myrtelle, indicate a potential breakthrough in the treatment of this rare and devastating neurodegenerative disorder.
Significant NAA Reduction and Brain Volume Increase
Cerebral spinal fluid (CSF) analyses from seven patients treated with MYR-101 showed reductions of over 80% in NAA levels from baseline, with follow-up data extending up to 24 months post-treatment. These findings were accompanied by observed increases in brain white matter and myelin volume on MRI scans during the same period. According to Olga Flamini, PhD, co-chief medical officer at Myrtelle, "The combination of changes in NAA levels and myelin volume offers a valuable tool for assessing early therapeutic efficacy in CD."
Functional Improvements Observed
In addition to the biomarker and structural improvements, patients treated with rAAV-Olig001-ASPA also exhibited functional gains on validated functional scales. This is particularly significant given the progressive nature of Canavan disease, where deterioration is typically expected in untreated individuals. These functional improvements, coupled with the biomarker and structural changes, suggest a potential disease-modifying effect of the gene therapy.
Regulatory Support and Accelerated Development
The FDA has recognized the potential of rAAV-Olig001-ASPA by including it in the Support for Clinical Trials Advancing Rare Disease Therapeutics (START) Pilot Program. This program aims to facilitate efficient communication between Myrtelle and the FDA, potentially accelerating the development and regulatory milestones for the therapy. Nancy Barone Kribbs, PhD, senior vice president of global regulatory affairs at Myrtelle, stated that acceptance into the START pilot program "recognizes rAAV-Olig001-ASPA as a candidate for accelerated development as a potential treatment for CD."
In addition to the START program, rAAV-Olig001-ASPA has been granted regenerative medicine advanced therapy (RMAT) designation, orphan drug designation (ODD), rare pediatric disease designation, and fast track designation by the FDA. The European Medicines Agency has also granted the therapy ODD and advanced therapy medicinal product classification.
Competitive Landscape
Myrtelle's rAAV-Olig001-ASPA is not the only gene therapy in development for Canavan disease. BridgeBio Pharma is also evaluating BBP-812, an AAV9 gene therapy, in a phase 1/2 clinical trial. BBP-812 recently received RMAT designation from the FDA based on 12-month data showing decreases in NAA levels in the urine and central nervous system of treated patients. Kathleen Flynn, BA, chief executive officer of National Tay-Sachs & Allied Diseases Association, highlighted the urgent need for effective treatments, stating, "It is a terminal diagnosis with no approved treatment to date."
