Clinical Trials

Date: 2018-04-03

Type of information: Recruitment of the first patient

phase: 3

Announcement: recruitment of the first patient

Company: Retrophin (USA - CA)

Product: sparsentan (RE-021)

Action mechanism:

endothelin receptor antagonist/angiotensin receptor blocker. Sparsentan has two separate mechanisms of action, acting as both an Endothelin Receptor Antagonist (ERA) and Angiotensin Receptor Blocker (ARB). Studies in similar nephropathies have shown ERAs and ARBs to both be effective in reducing proteinuria.
Ligand Pharmaceuticals licensed worldwide rights of sparsentan (RE-021) (formerly known as DARA) to Retrophin in 2012, at the time of Retrophin’s formation.

Disease: focal segmental glomerulosclerosis (FSGS)

Therapeutic area: Rare diseases - Kidney diseases - Renal diseases

Country: USA

Trial details:

The pivotal DUPLEX Study is a global, randomized, multicenter, double-blind, parallel-arm, active-controlled Phase 3 clinical trial evaluating the safety and efficacy of sparsentan for the treatment of FSGS. Approximately 300 patients, aged 8 to 75 years, are expected to be randomized to receive either sparsentan (initial dose of 400 mg daily for two weeks, titrating up to a target dose of 800 mg daily) or an active control - irbesartan (initial dose of 150 mg daily for two weeks, titrating up to a target dose of 300 mg daily).(NCT03493685)

Latest news:

• On April 3, 2018, Retrophin announced that the first patient has been enrolled in the DUPLEX Study, a global, pivotal Phase 3 clinical trial evaluating the long-term nephroprotective potential of sparsentan for the treatment of focal segmental glomerulosclerosis (FSGS).
In concurrence with FDA feedback, the DUPLEX Study protocol provides for an unblinded analysis of at least 190 patients (approximately 95 per treatment group) to be performed after 36 weeks of treatment to evaluate the interim efficacy endpoint – the proportion of patients achieving a modified partial remission of proteinuria (urine protein-to-creatinine ratio (Up/C) ?1.5 g/g and a >40 percent reduction in Up/C from baseline) at Week 36. Retrophin expects that successful achievement of this endpoint will serve as the basis for Subpart H accelerated approval of sparsentan in the United States and Conditional Marketing Authorization (CMA) consideration in Europe. The primary endpoint of the study is the change in slope of estimated glomerular filtration rate (eGFR) after 108 weeks of treatment. Secondary endpoints include the percent change in eGFR from Week 6 to Week 108, as well as the percent change from baseline in Up/C at Week 36 assessed at the final analysis. Top-line data from the 36-week interim efficacy endpoint analysis are expected in the second half of 2020.