On November 30, 2020, biopharmaceutical company Travere Therapeutics (“Travere”) announced that patient enrollment was complete for the Phase 3 DUPLEX clinical trial. Within the trial, researchers will evaluate the safety, efficacy, and tolerability of Sparsentan for patients with focal segmental glomerulosclerosis (FSGS). If this treatment is efficacious, it marks a less invasive treatment option; many patients with FSGS and end-stage kidney disease often require dialysis or a kidney transplant.
Within DUPLEX, researchers will analyze an investigational treatment called sparsentan, which combines:
endothelia type A receptor antagonism with angiotensin II receptor blockade.
Altogether, this dual action treatment is designed to reduce proteinuria and prevent disease progression. Sparsentan was developed for FSGS, as well as another rare kidney condition called IgA nephropathy. Thus far, sparsentan received both Orphan Drug and Orphan Medicinal Product designations.
The benefits of sparsentan were initially shown in the Phase 2 DUET clinical trial. During this trial, sparsentan was compared to Irbesartan. Ultimately, sparsentan reduced proteinuria at a much more significant rate than the other option. In addition to DUPLEX, Traverse will also hold a Phase 3 clinical trial (PROTECT) for IgA nephropathy. If both trials are successful, the data will go towards supporting a New Drug Application (NDA).
Within the fully enrolled DUPLEX trial, which enrolled 300 patients, researchers will compare sparsentan to Irbesartan. One of the efficacy endpoints is proteinuria remission. Data should be available within the first few months of 2021.
Focal Segmental Glomerulosclerosis (FSGS)
There are three types of focal segmental glomerulosclerosis (FSGS), a rare kidney disease in which scar tissue forms on the glomeruli, parts of the kidneys that filter waste from the blood. These three types are primary, secondary, and genetic/familial. Additionally, each specific type has its own cause. While primary FSGS is idiopathic (no known cause), secondary is caused from other conditions such as autoimmune disorders, obesity, sleep apnea, and kidney defects, and familial results from genetic mutations. Overall, FSGS is a lead cause of nephrotic syndrome and end-stage kidney disease. Symptoms include:
- Proteinuria (excess protein in the urine)
- High blood pressure, creatinine, and cholesterol
- Low blood albumin levels
- Swelling around the eyes, hands, feet, and abdomen
- Foamy urine
- Unintended weight gain