The combination of ofatumumab and lenalidomide is well-tolerated and induced durable responses in most patients with relapsed/refractory chronic lymphocytic leukemia (CLL), a study published in the journal Clinical Cancer Research has shown.1

For the phase 2 study, researchers sought to evaluate the efficacy and tolerability of the chemoimmunotherapy combination in patients with relapsed/refractory disease and investigate whether characteristics of the immune systems could impact treatment response.

Researchers enrolled 34 patients. All participants received ofatumumab 300 mg IV on day 1; 1000 mg on days 8, 15, and 22 during cycle 1; 1000 mg on day 1 during cycles 3 to 6; and once every other course during cycles 7 to 24. Cycles were 28 days long. Patients also started receiving lenalidomide 10 mg orally on day 9 until disease progression or unacceptable toxicity.


Continue Reading

Results showed that the overall response rate was 71%. A total of 8 patients (24%) achieved a complete remission or complete remission with incomplete recovery of blood counts. That included 9% of patients who had a minimal residual disease-negative complete remission.

Researchers found that the median progression-free survival was 16 months and the estimated 5-year survival was 53%.

In terms of safety, the most common treatment-emergent toxicity was neutropenia, which was higher than grade 2 in 18% of the 574 patient cycles. The most frequently reported infectious complications of treatment were pneumonia (24%) and neutropenic fever (9%).

RELATED: Long-term Survivors of CLL at Higher Risk for Other Cancers

The study demonstrated that patients who had higher baseline numbers and a better preserved function of T cells and natural killer cells were more likely to achieve a complete remission as compared with non-responders. This suggested that a competent immune system may play a role in supporting the efficacy of this therapy.

Reference

  1. Vitale C, Falchi L, ten Hacken E, et al. Ofatumumab and lenalidomide for patients with relapsed or refractory chronic lymphocytic leukemia: correlation between responses and immune characteristics [published online ahead of print January 5, 2016]. Clin Cancer Res. doi: 10.1158/1078-0432.CCR-15-2476.