Vinay K. Jain

Highlights From: 43rd Annual Meeting of the American Society of Hematology December 7–11, 2001 Orlando, Florida: First International Congress on Monoclonal Antibodies in Cancer August 30-September 2, 2001 Banff, Alberta, Canada

Rituximab has shown efficacy, and is approved for use, in relapsed nonHodgkin’s lymphoma (NHL) patients. However, its efficacy in refractory chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL) is variable, with responses seen in only 13% of patients in the pivotal trial,1 but in up to 57% of patients in other recently reported trials.2,3 Subset analysis of the 166 patients enrolled in the pivotal trial of rituximab in NHL, however, revealed that rituximab had a higher response rate (RR, 57%) in patients who had received only 1 prior chemotherapy regimen as compared to those who had received 2 or more previous chemotherapy regimens (38%),1 suggesting that rituximab may be more efficacious in patients who have received little or no chemotherapy prior to rituximab therapy. Dr Hainsworth has previously reported a phase II trial of rituximab as first-line therapy for 62 previously untreated patients with low-grade NHL, which showed that rituximab had a first-line RR of 47%, including 4 complete remissions (CR, 7%).4 Because retreatment of patients with progressive disease using rituximab has proven to be effective,5 maintenance courses of rituximab were given to responders in this trial as well, with an improved overall RR of 74% and a CR rate of 37%. Interestingly, the RRs in this phase II trial were similar among follicular and SLL patients at 76% and 70%, respectively. This trial has therefore been expanded to more fully study the role of first-line and maintenance rituximab in previously untreated CLL/SLL patients. The preliminary results of this trial were presented by Dr Hainsworth at the 2001 American Society of Hematology (ASH) Meeting held in Orlando, Florida.6 This trial enrolled patients with stage III/IV SLL or CLL and an Eastern Cooperative Oncology Group performance status of 0-2. No prior therapy was allowed. Treatment consisted of rituximab 375 mg/m2/week for 4 weeks, administered intravenously. Patients with an objective response or stable disease after the first treatment cycle received additional maintenance 4-week courses of rituximab every 6 months up to a maximum of 4 treatment cycles (2 years). Patients who experienced disease progression prior to 6 months

Highlights From: 6th European Hematology Association Meeting, Frankfurt, Germany June 21–24, 2001

Although CHOP (cyclophosphamide/ vincristine/doxorubicin/prednisone) is the standard of care for patients with aggressive non-Hodgkin’s lymphomas (NHL), CHOP has a cure rate of less than 40% in patients with advanced disease.1 In an effort to improve this cure rate, rituximab has been combined with CHOP chemotherapy in patients with diffuse large B-cell lymphoma (DLBCL). The combination of rituximab with CHOP is supported by preclinical data that suggest that synergistic interactions exist between doxorubicin and rituximab2; rituximab’s encouraging efficacy as a single agent in patients with aggressive NHL, its differing mechanisms of action, and its nonoverlapping toxicity profile also support this combination. In a phase II trial, rituximab/CHOP was shown to yield a complete remission in 61% of 33 patients with chemotherapy-naive aggressive NHL.3 Moreover, 29 of the 31 patients who achieved an objective response remained in remission for a median follow-up time of 26 months. The French Groupe d’Etudes des Lymphomes de l’Adulte (GELA) have undertaken a randomized phase III trial comparing rituximab/ CHOP to CHOP alone in elderly patients with chemotherapy-naive DLBCL. The results of a planned interim analysis on the first 328 patients was initially presented at the plenary session of the 2000 American Society of Hematology (ASH) Meeting held in San Francisco, California.4 The updated results, at 19 months of follow-up, were presented at the 2001 European Hematology Association (EHA) Meeting held in Frankfurt, Germany.5 This trial enrolled patients who were 60-80 years of age with stage II, III, or IV diffuse large-cell lymphoma and an Eastern Cooperative Oncology Group (ECOG) performance status (PS) between 0 and 2. Patients were randomized to treatHighlights prepared by Kavita Maung, PhD and Amy I. D’Orazio, PhD Reviewed by Bruce D. Cheson, MD and Vinay K. Jain, MD 6th European Hematology Association Meeting Frankfurt, Germany June 21-24, 2001 Highlights Meeting