Inotuzumab Ozogamicin in Indian Patients with B-Cell Acute Lymphoblastic Leukemia.

There is scarcity of data on utility of inotuzumab ozogamicin (InO) in relapsed refractory acute lymphoblastic leukemia in India. This is a retrospective study. Twelve patients (3 children) with a median age of 22.5 years (8-80 Years) were evaluated. Two patients received upfront InO therapy due to poor general condition. Four patients received IO due to persistent MRD positivity. Six patients had active disease of which 5 were multiply relapsed. Six patients received single-agent InO. Median number of cycles were 2 (1-6). All received inotuzumab on scheduled days and there was no treatment delay due to cytopenia. Ten patients (83%) achieved measurable residual disease (MRD) negative complete remission (CR). Seven of these ten patients became MRD-negative after 1 cycle only. All MRD-positive patients converted to MRD-negative remission. Four patients underwent allogeneic bone marrow transplant. Two patients continued standard maintenance therapy. Six patients succumbed. The median follow-up of the entire cohort is 10.7 months (2-32 months). Five out of twelve (41.6%) patients are alive and in MRD-negative remission at a median follow-up of 22 months (11-32 months). Inotuzumab ozogamicin is an effective agent for inducing deep remissions in patients with B-cell acute lymphoblastic leukemia.