FDA Approves Lumasiran for Primary Hyperoxaluria Type 1

The US Food and Drug Administration (FDA) has approved a new label expansion for lumasiran (OXLUMO), an RNAi therapeutic administered subcutaneously for the treatment of primary hyperoxaluria type 1 (PH1) to lower urinary oxalate (UOx) and plasma oxalate (POx) levels in pediatric and adult patients.

The approval, awarded to Alnylam Pharmaceuticals, is based on the results of the ILLUMINATE-C phase 3 trial in patients with severe renal impairment, including individuals on hemodialysis. PH1 is an ultra-rare genetic disease where oxalate is overproduced in the liver of patients.

The 6 month results from the study show the treatment resulted in substantial reductions in POx with an encouraging safety and tolerability profile in patients with compromised renal function, including patients with kidney failure and those undergoing hemodialysis. The results were positive for both dialysis-independent and dependent patients.

Both cohorts of patients saw a reduction in POx as early as month 1.

There was a 33% least squares mean reduction in POx the first cohort (n = 6) from baseline to month 6 (95% CI, -82% to 15%) and a 42% LS mean reduction in POx from baseline to month 6 in the second cohort (n = 15, hemodialysis dependent, 95% CI, -.51% to 34%).

There were no deaths or drug-related serious adverse events (SAEs) among patients, with 2 treatment discontinuations because of adverse events in the extension period that were not identified as drug related. The most common adverse event was mild and transient injection-site rection, which occurred in 24% (n = 5) of patients treated with lumasiran.

Also included in the New Drug Application (NDA) are results from open-label extensions of the ILLUMINATE-A and ILLUMINATE-B Phase 3 studies of pediatric and adult patients with PH1.

The excess production results in calcium, oxalate crystal deposits in the kidneys and urinary tract, which can lead to the formation of painful and recurrent kidney stones and nephrocalcinosis.

“The significance of the label expansion of OXLUMO cannot be overstated, as this milestone provides crucial reassurance among a patient population with the highest unmet need, as well as their caregivers and loved ones, that OXLUMO is available in the US for patients living with PH1, including those with advanced disease,” said Kim Hollander, Executive Director of the Oxalosis and Hyperoxaluria Foundation, in a statement.

Lumasiran was originally approved in 2020 for the treatment of PH1 to lower UOx levels in pediatric and adult patients.