Can cancer drugs combine forces?

Individuals with chronic myeloid leukemia (CML) are treated first with a drug known as imatinib (Gleevec), which targets the protein known to cause the cancer (BCR-ABL). If their disease returns, because BCR-ABL mutants emerge that are resistant to the effects of imatinib, individuals are treated with a drug known as dasatinib (SPRYCEL), which targets BCR-ABL in a different way.