The first patient with chronic spontaneous urticaria (CSU) has been dosed in Allakos Inc.’s Phase 1 trial of AK006.
AK006 is a humanized IgG1 monoclonal antibody which activates the inhibitory receptor Siglec-6. Siglec-6 is found on the surface of mature mast cells and offers a way to selectively target mast cells. In preclinical experiments, AK006 inhibits IgE-dependent and IgE-independent mast cell activation including activation through IgE, MRGPRX2, and KIT receptors. In these experiments, AK006 drives deep mast cell inhibition and, in addition to its inhibitory activity, can reduce mast cell numbers via antibody-dependent cellular phagocytosis in the presence of activated macrophages.
The Phase 1 trial is designed to assess the safety, tolerability, and pharmacokinetics of AK006 and to explore the therapeutic effects of AK006 in patients with CSU using the urticaria activity score (UAS7) at 14 weeks.
The CSU arm will enroll up to 60 adult patients with antihistamine refractory CSU (including patients with prior biologics treatment). Patients will be randomized 2:1 to receive intravenous AK006 or placebo once every four weeks (Q4W). The primary efficacy analysis will be the change in the urticaria activity score (UAS7) at week 14. Data from approximately 30 patients is expected at year end 2024.