Rivfloza Approved for Patients With Primary Hyperoxaluria Type 1 – Renal and Urology News

The Food and Drug Administration (FDA) has approved Rivfloza™ (nedosiran) to lower urinary oxalate levels in children 9 years of age and older and adults with primary hyperoxaluria type 1 (PH1) and relatively preserved kidney function (eg, estimated glomerular filtration rate (eGFR) ≥30mL/min/1.73m²).

Rivfloza is a small interfering RNA therapeutic that inhibits the expression of lactate dehydrogenase resulting in reduced production of oxalate by the liver. The approval was based on data from the double-blind, phase 2 PHYOX 2 trial (ClinicalTrials.gov Identifier: NCT03847909), which evaluated the efficacy and safety of nedosiran in patients 6 years of age and older with PH1 or PH2 and an eGFR of at least 30mL/min/1.73m². Study participants were randomly assigned to receive either nedosiran (n=23) or placebo (n=12) subcutaneously once monthly.

Results showed that treatment with nedosiran met the primary endpoint demonstrating a statistically significant reduction in 24-hour urinary oxalate excretion between day 90 and 180 from baseline compared with placebo (least-squares mean difference of AUC_{24-hour Uox}: 4976 [95% CI, 2803-7149]; P <.0001). The most common adverse reactions reported were injection site reactions. 

After 6 months, patients were eligible to enroll in an ongoing single-arm extension study (PHYOX3; ClinicalTrials.gov Identifier: NCT04042402). Reductions in 24-hour urinary oxalate excretion were maintained in the 13 patients with PH1 who received an additional 6 months of treatment.

“RNA interference is a proven treatment approach for individuals with PH1. With the approval of Rivfloza, we now have a novel treatment that lowers oxalate production safely and effectively,” said Dr David S. Goldfarb, MD Clinical Chief, Nephrology division, NYU Langone Medical Center and Professor of Medicine and Physiology, NYU Grossman School of Medicine in a statement. 

Rivfloza is supplied in single-dose prefilled syringes containing 128mg (0.8mL) and 160mg (1mL) of nedosiran, and in single-dose vials containing 80mg (0.5mL) of nedosiran. Treatment is administered by subcutaneous injection to the abdomen or the upper thigh; dosing is based on actual body weight.

The product is expected to be available in early 2024.

This article originally appeared on MPR