Daxxify Approved for Cervical Dystonia Treatment

The Food and Drug Administration (FDA) has approved Daxxify^® (daxibotulinumtoxinA- lanm) for the treatment of cervical dystonia in adults.

DaxibotulinumtoxinA-lanm is an acetylcholine release inhibitor and neuromuscular blocking agent. The approval was based on data from a double-blind, placebo-controlled trial (ASPEN-1; ClinicalTrials.gov Identifier: NCT03608397) that included patients with a clinical diagnosis of cervical dystonia with baseline Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) total score of at least 20, TWSTRS severity score of at least 15, TWSTRS disability score of 3 or greater, and TWSTRS pain score of 1 or greater (N=301). Eighty-four percent of these patients had previously received botulinum toxin as a treatment for cervical dystonia.

Study participants were randomly assigned to receive a single administration of 2.5mL of Daxxify 125 Units (n=125), Daxxify 250 Units (n=130), or placebo (n=46), divided amongst the affected muscles. The primary endpoint was the mean change in the TWSTRS total score from baseline averaged over weeks 4 and 6.

Compared with placebo, the mean change from baseline in the total TWSTRS score was significantly greater in the Daxxify 125U group (least squares mean [LSM] difference from placebo, -8.4 [95% CI, -12.2, -4.6]; P <.0001) and the Daxxify 250U group (LSM difference from placebo, -6.6 [95% CI, -10.4, -2.8]; P =.0007).

Median duration of effect (defined as time from treatment until loss of ≥80% of the peak effect) was reported to be 24 and 20.3 weeks in the Daxxify 125U and Daxxify 250U groups, respectively. Significant improvement with both dosages was also observed in the clinician global impression of change and patient global impression of change scales.

The most common adverse reactions reported were headache, injection site pain, injection site erythema, muscular weakness, and upper respiratory tract infection.

Daxxify is supplied as a lyophilized powder for reconstitution in single-dose 50 Unit and 100 Unit vials. The recommended dose for cervical dystonia ranges from 125 Units to 250 Units. Treatment is administered intramuscularly as a divided dose among affected muscles.