Celgene Announce Final Phase II Data Evaluating REVLIMID® and Rituximab

Celgene International Sàrl, a subsidiary of Celgene Corporation, announced final results from a phase II investigational study evaluating the combination of REVLIMID® (lenalidomide) and rituximab in 59 patients with relapsed or refractory chronic lymphocytic leukemia (CLL). These data were presented at the 53rd Annual Meeting of the American Society of Hematology in San Diego, CA.

In the study, 59 patients received rituximab 375 mg/m2 intravenously weekly for four weeks in cycle one, and then once every four weeks during cycles three to 12. Oral lenalidomide 10 mg/day was started on day nine of cycle one and then on a continuous dosing schedule. Cycles were 28 days with intention to continue therapy for 12 cycles or longer if the patient experienced a clinical response. Dose reductions were made for grade 3 or 4 hematological toxicity. Tumor lysis syndrome (TLS) prophylaxis comprising allopurinol 300 mg daily was administered during the first two weeks of cycle one.

All 59 patients were evaluable for response, with evaluations performed after cycles three, six, and every six cycles thereafter. In the study, the overall response rate was 66% (38/59) with seven patients (12%) achieving a complete response, seven patients (12%) achieving nodular partial responses, and 25 patients (42%) achieving partial responses.
At a median follow-up of 31 months, the estimated overall survival rate was 75%, and progression-free survival was 17.4 months.

Grade 3 or 4 hematologic toxicities included neutropenia (73%, n=43/59), thrombocytopenia (35%, n=20/59) and anemia (15%, n=9/59). Grade 3 or 4 infections occurred in 18 patients (31%). One patient experienced grade 3 TLS. Tumor flare reactions, all of which were grade 1 or 2, occurred in 16 patients (27%). Four deaths occurred during the study, including one due to stroke, one due to infectious exacerbation of chronic obstructive pulmonary disease and one from an unrelated cardiac arrhythmia. Colon cancer was diagnosed in one patient and myelodysplastic syndromes (MDS) in another, at 10 and six months after initiation of therapy, respectively. There were also two incidences of skin cancers and one recurrence of a head/neck cancer.

These data are from an investigational study. REVLIMID is not approved as a treatment for patients with chronic lymphocytic leukemia.