Add-on lenalidomide makes no difference in older acute myeloid leukaemia patients

The addition of lenalidomide shows no clear benefit for older patients with acute myeloid leukaemia (AML) receiving treatment with standard remission induction chemotherapy, according to data from a phase II trial.

A total of 222 patients (median age, 69 years) were randomized. Cycle 1 included daunorubicin at 45 mg/m² and cytarabine at 200 mg/m² with or without lenalidomide at the assigned dose level. Cycle 2 consisted of cytarabine 1,000 mg/m² from day 1 to 6 (12 doses) with or without lenalidomide at 20 mg/day 1–21. Patients could be allotransplanted off protocol according to local policy.

Of the patients, 216 (99 percent) received full doses of daunorubicin and 214 (98 percent) received full doses of cytarabine in cycle 1. Only 69 out of 107 patients (64 percent) received the full series of lenalidomide doses. The majority of the patients who discontinued treatment prematurely did so due to toxicity.

The number of patients who achieved complete remission (CR)/CR with incomplete haematologic recovery (CRi) did not differ between the standard arm and lenalidomide arm (69 percent vs 66 percent, respectively). The same was true for other outcomes. Event-free survival at 36 months was 19 percent vs 21 percent, respectively, while overall survival was 35 percent vs 30 percent.

Likewise, there were no significant differences in the frequencies and grade of adverse events between the treatment arms. Cardiovascular toxicities were uncommon and equally distributed.

Researchers pointed out that no definitive conclusion can be drawn on whether lenalidomide should be regarded as an inactive drug in AML, as the schedule of only two short cycles of application of the drug may have been inadequate.