Anti-KIT antibody: the next frontier in CSU treatment?

A novel anti-KIT antibody demonstrated high rates of well-controlled and fully controlled disease after 1 year of treating chronic spontaneous urticaria.

Baseline shows "very severely affected patients"

“CSU is a disease that still and urgently needs new treatment options,” Prof. Martin Metz (Charité University Hospital Berlin, Germany) stated1. At 12 weeks, the randomised-controlled phase 2 trial (NCT05368285), evaluating the humanised anti-KIT IgG1 monoclonal antibody barzolvolimab for the treatment of CSU, met its primary endpoint of mean change in UAS7 change from baseline. Currently, Prof. Metz presented the 52-week results after a further 36-week active treatment. For this extension, participants who previously receiving placebo or the 75 mg dose of barzolvolimab were re-randomised at week 16 to the other 2 regimens of either 150 mg every 4 weeks or 300 mg every 8 weeks.

“We are really looking at very severely affected patients,” Prof. Metz commented on the baseline characteristics. The mean age was between 42.2 and 47.2 years, 71–80% of the participants were women, 30.0–31.3% of the participants had a UAS7, and around 20% had previous experience with omalizumab.

Over 20-points drop in UAS7

The 12-week results showed a significant drop of over 20 points in UAS7 in the 150 mg and 300 mg groups compared with 10.47 points on placebo (P<0.0001 for both comparisons). At week 52, well-controlled disease with a UAS7 of ≤7 was achieved by 67.4–73.7% in the continuous verum groups. Complete disease control was found in 52.3–71.1%. “This is the best data for CSU that we have so far seen,” Prof. Metz highlighted.

“Most events that were seen were Grade 1 and most importantly mechanism-related,” Prof. Metz detailed with special regard to KIT-mediated safety events like hair colour changes (26%), skin hypopigmentation (13%), and neutropenia (17%) after 52 weeks. Treatment-related serious events happened in 1%.“Barzolvolimab has the potential to be an important new treatment option; phase 3 trials will give us more information on that,” he concluded.

Medical writing support provided by Karin Drooff, MPH

Source
  1.  Metz M. Barzolvolimab shows profound efficacy and favourable safety over 52 weeks in patients with chronic spontaneous urticaria. D1T01.2D, EADV Congress 2024, 25–28 September, Amsterdam, the Netherlands.