CD58 expression does not impact response to inotuzumab ozogamicin in patients with B-cell acute lymphoblastic leukemia.

Background: CD58 loss has been described as a mechanism of resistance to blinatumomab and chimeric antigen receptor T-cell therapy, functioning as a modulator of response to T-cell activation.

Methods: Using flow cytometry, we evaluated the impact of CD58 mean fluorescence intensity (MFI) on the probability of achieving measurable residual disease (MRD) negativity in patients with B-cell acute lymphoblastic leukemia treated with inotuzumab ozogamicin (InO).

Results: The odds ratio of achieving MRD negativity was 1.03 for every 1000 unit increase in CD58 MFI.

Conclusion: Our results suggest that MRD negativity rates after InO are high, regardless of the intensity of CD58 expression.