Dicerna Receives Breakthrough Therapy Designation for DCR-PHXC for Treatment of Primary Hyperoxaluria Type 1 (PH1)

Dicerna Pharmaceuticals, Inc. announced that the U.S. Food and Drug Administration (FDA) has granted a Breakthrough Therapy Designation (BTD) to DCR-PHXC for the treatment of patients with primary hyperoxaluria type 1 (PH1). DCR-PHXC is the only RNAi investigational therapy in development for the treatment of all types of PH, a family of severe, rare, inherited disorders of the liver that often result in kidney failure.

In its communication to Dicerna, the FDA also conveyed its determination that PH type 2 (PH2) and PH type 3 (PH3) meet the criteria for a serious or life-threatening disease or condition, based on the Agency’s standards. The Company will continue its ongoing dialogue with the FDA regarding endpoints for studies of DCR-PHXC in patients with PH2 and PH3, as part of the PHYOX clinical development program.

“By granting Breakthrough Therapy Designation, the FDA recognizes both the urgent need to develop a therapy for primary hyperoxaluria type 1 and the encouraging preliminary data from the PHYOX1 clinical trial of DCR-PHXC in these patients,” said Ralf Rosskamp, M.D., Dicerna’s chief medical officer. “We look forward to continuing our dialogue with the FDA as we advance DCR-PHXC as quickly as possible as a potential therapeutic option for all persons living with primary hyperoxaluria.”

The FDA’s BTD is intended to expedite the development and review of a drug candidate that is planned for use to treat a serious or life-threatening disease or condition when preliminary clinical evidence indicates that the drug may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints. The BTD offers companies the opportunity for increased communication with FDA and an organizational commitment involving more intensive guidance from FDA senior managers.

Dicerna recently presented updated data from the PHYOX1 Phase 1 clinical trial of DCR-PHXC, which reported substantial post-dose reductions in 24-hour urinary oxalate levels in adult and adolescent study participants with PH1 and PH2. The updated PHYOX1 data, presented at the Oxalosis and Hyperoxaluria Foundation’s International Workshop on June 22, 2019, also showed that a single dose of DCR-PHXC led to normalization or near-normalization of urinary oxalate levels in a majority of patients and was generally well-tolerated.