PTC Therapeutics Announces Completion of ST-920 Acquisition

What Happened
PTC Therapeutics, Inc. announced on September 21, 2026 that it completed the previously disclosed acquisition of ST‑920, a BLA‑stage one‑time AAV gene therapy candidate for Fabry disease, from Sangamo Therapeutics. The company issued a press release (furnished as Exhibit 99.1) and said a rolling biologics license application (BLA) submission to the FDA for accelerated approval is expected to be completed in the fourth quarter of 2026.

Key Details

• Acquisition completed: September 21, 2026; seller: Sangamo Therapeutics, Inc.
• Product: ST‑920 — one‑time AAV gene therapy candidate for Fabry disease (BLA‑stage).
• Regulatory timing: rolling BLA submission to FDA expected to be completed in Q4 2026.
• Basis for filing: 52‑week Phase 1/2 STAAR study showing meaningful favorable effect on renal function and a supportive safety/tolerability profile; company will also seek approvals outside the U.S.

Why It Matters
This acquisition adds a near‑term, BLA‑stage gene therapy to PTC’s pipeline, creating a clear regulatory milestone (BLA completion expected in Q4 2026) that investors can monitor. If the FDA accepts and ultimately approves ST‑920, it could represent a new product and revenue opportunity for PTC in the rare‑disease space; however, the filing and potential approval remain subject to regulatory review. The company’s planned pursuit of approvals outside the U.S. signals a global commercialization strategy for the candidate.