Drug improves upon standard therapy for relapsed CLL/SLL, speaker says

The incidence of grade 3/4 adverse events was 28.9% in the ibrutinib arm and 25% in the placebo arm. The most common of these were neutropenia (53.7% vs 50.5%) and thrombocytopenia (15% in both arms).

Atrial fibrillation was seen in 7.3% of patients in the ibrutinib arm and 2.8% in the placebo arm. Grade 3/4 atrial fibrillation occurred in 2.8% and 0.7% of patients, respectively. The incidence of tumor lysis syndrome was 3.5% in both arms.

The rate of bleeding was 31% in the ibrutinib arm and 14.6% in the placebo arm. And the rates of major hemorrhage were 3.8% and 1.7%, respectively.

Adverse events were the primary reason for discontinuation in patients who received ibrutinib—14.2%, compared to 11.8% of patients who received placebo. The primary reason for discontinuation in the placebo arm was progressive disease or relapse—45%, compared to 4.8% in the ibrutinib arm.

Taken together, the results of this trial suggest treatment with ibrutinib and BR is superior to standard BR therapy in patients with relapsed CLL/SLL, Dr Chanan-Kahn said.

“This was one of the most rigorous clinical trials ever conducted in CLL,” he said, “and it truly validates ibrutinib as an important drug for this cancer.”