BridgeBio Submits NDA for BBP-418 in LGMD2I/R9, Potentially the First Approved Therapy for Any Form of Limb-Girdle Muscular Dystrophy

BridgeBio Pharma announced the submission of a new drug application (NDA) to the FDA for oral BBP-418 for the treatment of limb-girdle muscular dystrophy type 2I/R9 (LGMD2I/R9), an autosomal recessive neuromuscular disease with no currently approved disease-modifying therapies.¹

The comprehensive NDA package includes interim data from the phase 3 FORTIFY clinical trial (NCT05775848), which met all prespecified primary and secondary end points at 12 months and demonstrated statistically significant improvements in both ambulatory and pulmonary function. BridgeBio anticipates that if approved, a US launch could occur in late 2026 or early 2027. The company also noted that it is currently engaging European regulators to identify an expedited approval pathway there.

BBP-418 has previously received orphan drug, fast track, and rare pediatric disease designations from the FDA, as well as orphan drug designation from the European Medicines Agency (EMA). With the fast track designation and the absence of any approved therapy in the indication, the NDA for BBP-418 may be eligible for Priority Review in the United States. Furthermore, if BBP-418 is approved, BridgeBio may qualify for a Priority Review Voucher as a result of the rare pediatric disease designation.

“This NDA submission brings us one step closer to delivering the first approved therapy to individuals and families affected by LGMD2I/R9, a severe, progressive neuromuscular disease,” Christine Siu, MBA, BS, the chief executive officer of BridgeBio Neuromuscular, said in a statement.¹ “This achievement not only reflects the strength of the data, but also our dedicated focus on addressing the urgency of a community that has long been waiting for meaningful treatment options. We are committed to working closely with the FDA to make this potential disease-modifying therapy available as quickly as possible.”

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Late last year, BridgeBio announced positive topline results from FORTIFY, which is a randomized, double-blind, placebo-controlled study.² In the primary interim analysis end point, findings at 3 months showed a highly statistically significant 1.8-fold increase from baseline (~ 17% of control; P <.0001) of glycosylated α-dystroglycan (αDG) in the BBP-418–treated group, compared with approximately no change in the placebo group. Additional data demonstrated that elevations in glycosylated αDG in the BBP-418 treatment group were highly statistically significant and remained durable through 12 months (P <.0001).

Marked and highly statistically significant gains in glycosylated αDG were observed regardless of whether patients carried the L276I homozygous genotype or another FKRP genotype. Additionally, mean serum creatine kinase—a biomarker of muscle fiber injury—fell by 82% from baseline among BBP-418–treated participants (P <.0001). The company also reported that BBP-418 was well tolerated, with no new or unexpected safety findings observed. BridgeBio noted at the time that as a result of these findings it would soon begin engaging with the FDA regarding a potential NDA submission.

"I’m very excited to see that treatment with BBP-418 was associated with clinically meaningful improvements in motor and pulmonary function, along with robust restoration of αDG glycosylation,” Katherine Mathews, MD, professor of pediatrics and neurology at the University of Iowa’s Roy J. and Lucille A. Carver College of Medicine, said in an October 2025 statement.¹ “This is such an important result for individuals living with LGMD2I/R9, which is a progressive muscular dystrophy. The resulting weakness often leads loss of ambulation, need for respiratory support, and need for heart failure medications. To date, there has been no specific treatment. These results bring enormous hope that BBP-418 might change the disease course.”

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REFERENCES
1. BridgeBio Pharma. BridgeBio submits New Drug Application to FDA for BBP-418 for individuals living with LGMD2I/R9. News release. BridgeBio Pharma, Inc. March 30, 2026. Accessed March 30, 2026. https://investor.bridgebio.com/news/news-details/2026/BridgeBio-Submits-NDA-to-FDA-for-BBP-418-for-Individuals-Living-with-LGMD2IR9/default.aspx
2. BridgeBio Reports Positive Phase 3 Results for Small Molecule BBP-418 in LGMD2I/R9 FORTIFY Study. News release. October 27, 2025. Accessed November 12, 2025. https://investor.bridgebio.com/news/news-details/2025/BridgeBio-Reports-Positive-Phase-3-Results-for-Small-Molecule-BBP-418-in-LGMD2IR9-FORTIFY-Study/default.aspx