Disclosed herein are methods, compositions, and kits for treating a B-cell malignancy comprising administering a combination of a BTK inhibitor (e.g. ibrutinib) and a PIM inhibitor. Also disclosed herein are methods, compositions, and kits for treating a BTK-resistant B-cell malignancy comprising administering a combination of a BTK inhibitor (e.g. ibrutinib) and a PIM inhibitor.