In another phase 2 trial of ponatinib (OPTIC), which introduced response-based dosing, patients with CP-CML resistant to or intolerant of ≥2 prior BCR::ABL1 TKIs or with a BCR::ABL1 T315I mutation were randomized to receive three different starting doses (45, 30, or 15 mg once daily) of ponatinib and in the 45-mg and 30-mg cohorts, doses were reduced to 15 mg upon achievement of BCR::ABL1 transcript on the international scale (BCR::ABL1IS) ≤1%. The gene discussed is ABL1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.