Avidity slumps as FDA stops new enrollement in AOV 1001 trial

Shares in Avidity Biosciences (Nasdaq: RNA) were down as much as 26% on the news that the US Food and Drug Administration (FDA) has placed a partial clinical hold on new participant enrollment in the Phase I/II MARINA clinical trial of AOC 1001 - an antibody-oligonucleotide conjugate (AOC) - in adults with myotonic dystrophy type 1 (DM1). However, the stock partly recovered, closing yesterday’s trading 10.9% lower at $16.70.

Close to 40 participants are currently enrolled in the MARINA and MARINA open label extension (MARINA-OLE) trials. All participants, whether they are on AOC 1001 or placebo, may continue in their current dosing cohort although no additional participants may be enrolled until the partial clinical hold is resolved. All participants in MARINA may roll over into the MARINA-OLE where they will receive AOC 1001 as planned. DM1 is an underrecognized, progressive and often fatal neuromuscular disease with no approved treatment options.

The partial clinical hold is in response to a serious adverse event reported in a single participant in the 4mg/kg cohort of the MARINA study. Avidity is working closely with the FDA and the trial investigator to assess the cause of this event. The company is taking all necessary steps to resolve the partial clinical hold on new participant enrollment as quickly as possible.