Open-Label Extension Study of BBP-418 (Ribitol) for LGMD2I/R9

This is an open-label extension (rollover) study designed to evaluate the long-term safety and efficacy of BBP-418 (ribitol) in participants with limb-girdle muscular dystrophy type 2I/R9 (LGMD2I/R9) who have previously participated in Study MLB-01-005 (Fortify). Participants will receive BBP-418 administered orally at protocol-defined doses and schedules. The study will assess long-term safety through monitoring of adverse events, clinical laboratory evaluations, and other safety assessments. Efficacy will be evaluated using functional measures and other clinical endpoints relevant to LGMD2I/R9. Participants will be followed for up to 36 months, with a final safety follow-up assessment conducted approximately 30 days after the last dose of study drug.

Inclusion Criteria: * Completed Study MLB-01-005 on study drug through the final clinic visit (Month 36 or another qualifying end-of-study visit as determined by the Sponsor). * The participant (or parent/guardian) who signs the ICF understands the study procedures and agrees to participate in the study by giving informed consent (or assent, if \