Vertex Advances Oral Therapy to Phase III for Kidney Disease, Aims for Fast-Track Approval

Vertex Pharmaceuticals has recently initiated the Phase III segment of the AMPLITUDE clinical trial, focusing on the potential of inaxaplin, an experimental oral medication, for treating APOL-1 mediated kidney disease (AKMD). The study aims to compare the impact of a daily 45-mg dose of inaxaplin to a placebo on kidney function and proteinuria in affected patients, who will also continue to receive standard care.
The AMPLITUDE trial includes a pre-planned interim analysis at 48 weeks, which will measure the estimated glomerular filtration rate (eGFR) to assess kidney function. Positive results could lead Vertex to pursue accelerated approval for inaxaplin. The company's Chief Medical Officer, Carmen Bozic, has highlighted inaxaplin's innovative nature, noting its potential to address the root cause of AKMD and the importance of expanding the trial to include younger demographics.
The Phase III advancement follows the successful completion of the Phase IIa proof-of-concept phase, with results indicating a significant reduction in proteinuria after 13 weeks of inaxaplin treatment. The drug was found to be generally well-tolerated, with common side effects including headache, back pain, and nausea. Vertex has stated that these Phase II findings provide the first clinical evidence that an oral small molecule targeting APOL1 could effectively reduce proteinuria in AKMD patients.
AKMD is a chronic kidney disease that affects approximately 100,000 patients in the U.S. and Europe, resulting from genetic variations in the APOL1 gene. These mutations can lead to kidney cell damage, protein in the urine, impaired kidney function, and potentially fatal outcomes. Inaxaplin works by inhibiting APOL1, and it has already received the FDA's Breakthrough Therapy designation, which facilitates a faster review process for the drug.