Ponatinib (Iclusig), bosutinib (Bosulif), and omacetaxine (Synribo) are enhancing treatment for persons with certain forms of leukemia, according to Jorge Cortes, MD, deputy chair of the Department of Leukemia at The University of Texas MD Anderson Cancer Center in Houston, who led the facility’s clinical trials for the three drugs.
“It’s important to have as many therapies as we can, because rarely does one drug or combination succeed for all patients,” explained Cortes. For example, although imatinib (Gleevec), nilotinib (Tasigna), and dasatinib (Sprycel) have shown strong efficacy in persons with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) or chronic myelogenous leukemia (CML), up to 60% of persons with CML do not respond to these tyrosine kinase inhibitors (TKIs). Ponatinib is expected to drastically improve outcomes for patients with CML and Ph+ALL.
Bosulif is a second-generation TKI that works as well as dasatinib and nilotinib, according to Cortes. “The significant difference is bosutinib is more specific in its activity, inhibiting [disease-causing] BCR-ABL and SCR, but not other tyrosine kinases; this leads to fewer harsh side effects.”
Omacetaxine is a synthetic version of the CML drug homoharringtonine, which is derived from an evergreen tree found in China. It works in a completely different manner in that it stifles creation of the aberrant BCR-ABL protein rather than blocking the protein’s activity.
“This is an important option for patients who’ve had several tyrosine kinase inhibitors fail and for those who cannot tolerate those drugs,” observed Cortes. ONA