Vertex Announces Inaxaplin (VX-147) Granted Breakthrough Therapy Designation by U.S. FDA and Priority Medicines (PRIME) Designation by the EMA

Vertex Pharmaceuticals Incorporated (Nasdaq: VRTX) today announced the U.S. Food and Drug Administration (FDA) has granted inaxaplin (VX-147) Breakthrough Therapy Designation for APOL1-mediated focal segmental glomerulosclerosis (FSGS) and the European Medicines Agency (EMA) has granted inaxaplin Priority Medicines (PRIME) designation for APOL1-mediated chronic kidney disease (AMKD). Inaxaplin is the first investigational therapy aimed at treating the underlying cause of AMKD.

The FDA's Breakthrough Therapy Designation is intended to expedite development and review of medicines that aim to address a serious condition with preliminary clinical evidence indicating that the drug may demonstrate substantial improvement over existing treatments on one or more clinically significant endpoints. The Breakthrough Therapy Designation was granted based on the Phase 2 clinical study of inaxaplin in patients with APOL1-mediated FSGS, a form of AMKD.

The EMA’s PRIME designation is a regulatory mechanism that provides early and proactive support to developers of promising medicines, to optimize the generation of robust data and enable accelerated assessment so these medicines can potentially reach patients faster. The goal of PRIME is to help patients benefit as early as possible from innovative new therapies that have the potential to significantly address an unmet medical need. PRIME designation was granted based on clinical proof-of-concept data from Vertex’s Phase 2 study of inaxaplin in APOL1-mediated FSGS. Inaxaplin is only the second nephrology product to be granted PRIME designation.

Vertex now holds three of the approximately 70 non-oncological PRIME designations granted to date, including its two PRIME designations for exagamglogene autotemcel (exa-cel), formerly known as CTX001, one for transfusion-dependent beta thalassemia and one for sickle cell disease. In the US, this is the ninth breakthrough therapy designation granted to Vertex across its portfolio programs.

About the Inaxaplin (VX-147) Pivotal Program
A randomized, double-blind, placebo-controlled Phase 2/3 adaptive study is ongoing and will first evaluate two doses of inaxaplin for 12 weeks to select a dose for Phase 3 and subsequently evaluate the efficacy and safety of the single, selected dose in the Phase 3 portion of the study.

Patients aged 18 to 60 years, with two APOL1 mutations, urine protein to creatinine ratio (UPCR) ≥0.7 g/g to <10 g/g, estimated glomerular filtration rate (eGFR) ≥25 to <75 mL/min/1.73m² and on stable doses of standard of care medications are eligible to enroll. Approximately 66 patients are planned to be enrolled in the Phase 2 dose-ranging portion of the study, and approximately 400 additional patients are planned to be enrolled in the Phase 3 portion of the study.