Novel targeted therapies in acute lymphoblastic leukemia.

Chemotherapy alone cures only 25-45% of adult patients with acute lymphoblastic leukemia (ALL), making novel treatment agents and strategies desperately needed. The addition of monoclonal antibodies (rituximab, alemtuzumab, epratzumab) to chemotherapy has demonstrated encouraging results in patients with newly diagnosed and relapsed ALL. The anti-CD22 immunoconjugate, inotuzumab ozogamicin, and the anti-CD19 BiTE(®) antibody, blinatumomab, have demonstrated impressive single agent activity in patients with relapsed or refractory B-ALL. Early reports of chimeric antigen receptor therapies have been promising in patients with relapsed ALL. Other agents targeting NOTCH1, FLT3, the proteasome and DNA methylation are early in development. These new agents hope to improve the outcome of ALL therapy with less toxicity. The challenge going forward will be to find safe and effective combinations and determine where in the treatment schema these agents will be most effective in ALL therapy.