Rolling submission for Elzonris submitted to FDA for blastic plasmacytoid dendritic cell neoplasm.- Stemline Therapeutics.

Stemline Therapeutics announced that it has completed submission of a rolling Biologics License Application (BLA) to the FDA for Elzonris (tagraxofusp; SL-401), a potential treatment for patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN), a CD123+ malignancy of unmet medical need for which the agent was awarded Breakthrough Therapy Designation (BTD). The trial of investigational agent, Elzonris, in patients with BPDCN was comprised of 3 stages, with Stage 3 serving as the pivotal cohort for confirmation of efficacy. To ensure ongoing access to Elzonris, patients with BPDCN are being enrolled in an additional cohort, Stage 4.

Stage 3 met its primary endpoint with a CR+CRc (complete response + clinical complete response) rate of 54% (95% CI: 25.1, 80.8). In first-line BPDCN patients who received Elzonris (12mcg/kg/day) in Stages 1, 2 and 3, the median OS has not been reached. Median follow up was 13.8 months (range: 0.2-37.4+ months).