DNLI's BLA for Hunter Syndrome Drug Gets FDA's Priority Review

Core Insights - Denali Therapeutics, Inc. (DNLI) has received FDA acceptance for its biologics license application (BLA) for tividenofusp alfa, aimed at treating Hunter syndrome, with a target action date set for January 5, 2026 [1][7] - The acceptance of the BLA marks a significant step for DNLI towards becoming a commercial-stage biotech company, especially as its shares have declined by 30.1% year to date [2] Drug Development and Clinical Trials - Tividenofusp alfa has received Breakthrough Therapy Designation from the FDA for Hunter syndrome, a rare genetic disorder caused by a deficiency in the iduronate 2-sulfatase (IDS) enzyme [3] - The drug is designed to cross the blood-brain barrier, addressing both cognitive and physical symptoms of MPS II, unlike traditional enzyme replacement therapies [4] - The BLA submission is supported by data from a phase I/II study involving 47 participants, and an ongoing phase II/III COMPASS study is expected to provide pivotal data for global regulatory filings [5] Pipeline and Collaborations - Denali is also evaluating DNL126 for Sanfilippo syndrome type A and has engaged in discussions with the FDA for an accelerated development path [9] - Another candidate, DNL593, is being co-developed with Takeda for frontotemporal dementia, with an ongoing phase I/II study [10] - Denali and Biogen are jointly developing a LRRK2 inhibitor for Parkinson's disease, with a global phase IIb study fully enrolled and results expected in 2026 [11] - Denali is also conducting a phase IIa study for LRRK2-associated Parkinson's disease and evaluating DNL343 for amyotrophic lateral sclerosis (ALS), although a primary endpoint was not met in a recent trial [12] - The company has multiple early-stage clinical and preclinical programs and maintains a sound cash position to fund ongoing initiatives [13]