Celldex reported that both of its phase 3 barzolvolimab studies in chronic spontaneous urticaria cleared every major efficacy hurdle at 12 weeks, with gains that held or improved by week 24.
In the primary endpoint, weekly urticaria activity score fell by 20.2 points in the 150 mg every-4-weeks arm and by 20.5 points in the 300 mg every-8-weeks arm in EMBARQ-CSU1, versus a 10.7-point decline on placebo. In EMBARQ-CSU2, the reductions were 20.2 points and 19.7 points, respectively, versus 11.4 points on placebo. All comparisons were reported with p-values below 0.00001.
The complete-response numbers widened sharply over time. At 12 weeks, UAS7=0 was reached by 42.4% and 42.1% of patients on the two barzolvolimab regimens in EMBARQ-CSU1, versus 9.3% on placebo. In EMBARQ-CSU2, the rates were 45.7% and 44.0%, versus 12.6% on placebo. By 24 weeks, the complete-response rates had risen to 49.0% and 45.1% in EMBARQ-CSU1, and to 54.0% and 48.4% in EMBARQ-CSU2, while placebo was at 15.4% and 17.6%.
Among patients with omalizumab-refractory disease, complete response at week 12 was 55.3% and 44.3% in EMBARQ-CSU1, versus 9.3% on placebo. In EMBARQ-CSU2, the corresponding figures were 41.7% and 46.4%, versus 15.1% on placebo.
For angioedema, the proportion of patients with AAS7=0 at week 12 among those with baseline angioedema was 62.7% and 66.3% in EMBARQ-CSU1, compared with 33.8% on placebo. In EMBARQ-CSU2, those rates were 74.3% and 66.2%, versus 33.7% on placebo.
The program enrolled 1,939 patients in total, with 963 in EMBARQ-CSU1 and 976 in EMBARQ-CSU2. Celldex said treatment will continue through 52 weeks, with a biologics license application planned for 2027. The market has reacted to these announcements by moving the company's shares -10.64% to a price of $33.86. For the full picture, make sure to review Celldex Therapeutics's 8-K report.
