CD33 and systemic mastocytosis: CD16 × IL-15 × CD33 TriKE is being evaluated in phase I and II clinical trials in patients with advanced systemic mastocytosis, relapsed or refractory AML, or CD33-expressing high-risk myelodysplastic syndromes NCT03214666 (Wiernik et al., 2013; Schmohl et al., 2016; Schmohl et al., 2017).