Key clinical point: Inotuzumab ozogamicin with bosutinib was well tolerated in patients with relapsed/refractory (R/R) lymphoid blast phase of chronic myeloid leukemia (CML-LBP) and Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL).
Major finding: Rates of complete response (CR)/CR with incomplete count recovery, complete cytogenic response, measurable residual disease negativity, and complete molecular response were 83%, 81%, 61%, and 56%, respectively. The 30-day mortality was 0%. During the median follow-up of 44 months, median event-free survival and overall survival were 7.7 and 13.5 months, respectively. No patients discontinued treatment because of toxicity, and no veno-occlusive disease was reported.
Study details: This was a phase 1/2 trial including 18 patients with R/R Ph+ALL (n=16) or CML-LBP (n=2). The maximum tolerated dose of bosutinib was 400 mg daily.
Disclosures: This study was funded by Pfizer, MD Anderson Cancer Center Support Grant, and the National Cancer Institute. Some investigators including the lead author reported ties with various pharmaceutical companies, including Pfizer.
Source: Jain N et al. Am J Hematol. 2021 May 15. doi: 10.1002/ajh.26238 .