Biopharmaceutical firm Retrophin has reported that the Phase III clinical trial of fosmetpantotenate failed to meet endpoints in pantothenate kinase-associated neurodegeneration (PKAN) patients.
PKAN is a rare, genetic neurological disease that causes progressive, debilitating symptoms such as movement disorders and visual impairment.
It develops due to the PANK2 gene mutation, which impacts the production of coenzyme A (CoA) needed for various biochemical reactions in the body.
Fosmetpantotenate is an investigational small molecule developed as replacement therapy to cross the blood-brain barrier and be converted to phosphopantothenate (PPA) in order to restore CoA levels.
The Phase III FORT trial evaluated the safety and efficacy of fosmetpantotenate in 84 patients administered with a three-times-daily dose of fosmetpantotenate or placebo for 24 weeks.
Change in the PKAN-ADL scale from baseline to 24 weeks of therapy was measured as the primary endpoint of the international, double-blind, randomised, placebo-controlled trial.
The secondary outcome was the change in the Unified Parkinson’s Disease Rating Scale (UPDRS) Part III score.
Results showed that fosmetpantotenate did not meet the primary and secondary endpoints, with no differences observed between the treatment groups.
The investigational candidate was generally safe and well-tolerated.
Retrophin CEO Eric Dube said: “We are very disappointed in the top-line results from the FORT Study, particularly because we have seen the devastating impact of PKAN on patients and their families, and a significant unmet need remains with no approved treatment option.
“We will work closely with the investigators to further analyse the results of the study and share them with the PKAN community to contribute to the growing knowledge of this rare disorder.”
The company will plan the next steps for the Phase III trial, including its ongoing open-label extension study.
Retrophin will also continue to work on its Phase III programmes of sparsentan in focal segmental glomerulosclerosis (FSGS) and IgA nephropathy, while also advancing its commercial products.