Ribitol Decreased Muscle Breakdown and Improved Function in Limb-Girdle Muscular Dystrophy

In a phase 2 study, individuals treated with ribitol (BBP-418; BridgeBio Pharma, Palo Alto, CA) for limb girdle muscular dystrophy type 2i (LGMD2i) for 12 months had a mean 75% reduction in creatine kinase (CK) levels—a marker of muscle degeneration. A mean 0.95-point improvement from baseline on the North Star Assessment for Dysferlinopathy (NSAD) (0.95) occurred. The 10-meter walk test (10MWT) mean velocity improved by 0.09 m/second as well.

“LGMD2i dramatically impacts individuals living with the disease, fundamentally robbing people of their independence. As the disease progresses, individuals with LGMD2i lose the ability to function unaided, eventually (requiring a wheelchair for mobility) and requiring ventilation assistance, the timing of which is dependent on the severity of their disease. Our phase 2 data show our investigational therapy continues to be well-tolerated and may have the potential to improve or slow clinical decline associated with the disease,” said Douglas Sproule, MD, MSc, chief medical officer of ML Bio Solutions, a BridgeBio affiliate that is focused on developing ribitol for LGMD2i.

The phase 2 trial enrolled 14 participants who had both ambulatory and nonambulatory LGMD2i. No treatment-related serios adverse events or dose limiting toxicities. These results were presented at the 27th International Hybrid Annual Congress of the World Muscle Society (WMS) on October 11-15, 2022.

“The continued positive data from this study are encouraging. In addition to being well-tolerated, the consistent improvements observed in both important biomarkers of muscle function as well as in clinical endpoints form a compelling proof of concept for BBP-418 in patients with LGMD2i,” said Amy Harper, MD, professor in the department of neurology at Virginia Commonwealth University (VCU) and primary investigator of the phase 2 clinical trial in LGMD2i. “These patients represent a serious unmet need, and it is exciting to see this treatment progress towards a phase 3 study that may allow it to serve that need.”