Fludarabine in combination with cyclophosphamide is an effective treatment for newly diagnosed as well as relapsed follicular lymphoma. The anti-CD20 antibody rituximab has been employed successfully for the same indications. No such data were available on a combined use of these agents. Therefore, we conducted a phase II study to evaluate the safety and efficacy of a combination of rituximab (375 mg/m2), fludarabine (4 x 25 mg/m2) and cyclophosphamide (1 x 750 mg/m2), for the treatment of relapsed follicular lymphoma. An unexpected, severe hematologic toxicity with significant, prolonged thrombocytopenias WHO grade III/IV in 6 (35%) of 17 patients treated in total occurred, leading to early termination of the trial. Cytologic and serologic analyses point toward a direct toxic effect. Older patients (mean age 64.7 vs. 56.5 yr) were significantly (P = 0.02) more likely to suffer from this toxicity, whereas no other clinical or hematologic parameter differed statistically between the patients suffering from thrombocytopenia and those who did not. The addition of rituximab to fludarabine/cyclophosphamide employed at doses given above in relapsed follicular lymphoma may have led to this increase in thrombocytopenias. Therefore, caution should be exercised when combining these drugs for the treatment of patients with relapsed follicular lymphoma, especially when treating older patients.
Purpose: The combination of chemotherapy with the chimeric anti-CD20 antibody Rituximab has been reported to be highly active in the treatment of follicular lymphoma. The frequency and dosage of rituximab required to induce the maximum effect in follicular NHL is not defined. To evaluate how often rituximab should be added to standard chemotherapy to achieve maximum remission rates, we have initiated a prospective randomized multicenter phase II study.
Methods: Patients (pts) with stage III/IV CD20 positive follicular NHL who were chemotherapy naïve were randomly assigned to receive 6 courses of a standard CHOP-21 chemotherapy, accompanied by rituximab 375 mg/m2 at day 0 only with the first CHOP course (arm A), with the first 3 CHOP courses (arm B) or with all 6 CHOP courses (Arm C). The major endpoint was the rate of molecular remission in bone marrow and peripheral blood in initially t(14;18)-positive pts, assessed by PCR. Other endpoints of the study were overall and complete response rates, toxicity rate and time to progression.
Results: Since September 2000, 104 pts with a median age of 57 years (range 30–80) were recruited. 33 pts were randomized to arm A, 35 to arm B and 36 to arm C. So far 69 pts have been documented completely after all 6 cycles and are evaluable for side effects. All three treatment arms were well tolerated. The incidence of adverse events and Grade 4 toxicity was similar in all groups. One treatment related death was observed 2 months after completion of therapy due to hepatitis B. The overall response rate (ORR) of the whole group, which was evaluable in 69 pts so far, was 90 % (62 of 69 pts), with 20 complete and 42 partial remissions.
Conclusion: This multicenter, randomized, phase II trial addresses for the first time the optimal frequency and dosage of rituximab infusions in the combined immuno-chemotherapy. In the first interim analysis of the ongoing trial, similar hematologic, gastrointestinal and infectious toxicity was observed in all treatment arms.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.