Rivfloza (nedosiran) is a medication used to lower urinary oxalate levels in specific patients with hyperoxaluria type 1 (PH1). Primary hyperoxaluria type 1 is a genetic disorder where there is an overproduction of oxalate, which results in too much oxalate in the urine and this causes kidney stones and chronic kidney disease, among other complications. Rivfloza works to lower oxalate levels by decreasing an enzyme (hepatic lactate dehydrogenase (LDH)) involved in making oxalate.

Rivfloza is an LDHA-directed small interfering RNA medicine. Rivfloza is usually given as an injection under the skin (subcutaneously) once a month.

Rivfloza became an FDA-approved medicine on September 29, 2023, after positive results from a randomized, double-blind trial called PHYOX2. This trial assessed the average 24-hour urinary oxalate excretion at various intervals (90, 120, 150, and 180 days). Rivfloza reduced the urinary oxalate excretion level by 37%, and the placebo group levels increased by 12%, with the difference between the group being 49%.

Who can use Rivfloza?

Rivfloza is an FDA-approved medicine to treat primary hyperoxaluria type 1 (PH1) in patients 9 years of age and older who have relatively preserved kidney function (GFR ≥ 30 mL/min/1.73 m2).

Use Rivfloza exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets.

Rivfloza is usually given as an injection under the skin (subcutaneously) once a month.

Your healthcare provider will prescribe the dose that is right for you based on your body weight.

Rivfloza comes as a single-dose Pre-filled Syringe and a single-dose vial. 

Your healthcare provider will show you how to prepare and inject this medicine. 

Do not try to inject this medicine until you have been shown the right way by your healthcare provider. 

For children 9 to 11 years of age weighing 110 pounds (50 kilograms) or more, it is recommended that the Pre-filled Syringe be given by a healthcare provider or caregiver. 

Rivfloza Dosage forms and strengths

• 80 mg (0.5 mL) single-dose vial 
• 128 mg (0.8 mL) single-dose Pre-filled Syringe 
• 160 mg (1 mL) single-dose Pre-filled Syringe 

Pregnancy

Tell your healthcare provider if you are pregnant or plan to become pregnant. There is not enough data from reports of pregnancy in clinical trials with Rivfloza to know if it will harm your unborn baby.

Breastfeeding

Tell your healthcare provider if you are breastfeeding or planning to breastfeed, as It is not known if Rivfloza passes into your breast milk. Talk to your healthcare provider about the best way to feed your baby during treatment with this injection. 

If you miss a dose of Rivfloza, inject the dose as soon as possible.

If you miss a dose by more than 7 days, inject the dose as soon as possible and resume monthly dosing from the most recently injected dose. Call your healthcare provider or pharmacist if you have questions about a missed dose.