Which Drug Interaction Is Responsible for This Patient's Myelosuppression?

Upon laboratory testing, SL, a 64-year-old female diagnosed with Philadephia chromosome–positive (Ph+) ALL, was found to be anemic (Hgb=7 g/dL) (Slide 2) and neutropenic (ANC=600 cells/mcL) after her second course of maintenance therapy.

Relevant Medical History

• Currently, SL is taking vincristine, prednisone, methotrexate, and mercaptopurine (POMP) + dasatinib maintenance therapy for her Ph+ ALL
• Recently complained of occasional heartburn

Laboratory History

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