Safety and Efficacy in Patients Receiving Maintenance Rituximab for Follicular Lymphoma: Early Results From Phase IIIb MAXIMA Trial.

Rituximab maintenance therapy applied for two years after a successful induction with immuno-chemotherapy with rituximab has become standard of care in patients with relapsed follicular lymphoma (FL). The primary objective of this global study (24 countries) is to evaluate the safety of rituximab maintenance therapy. Secondary objective is to assess the efficacy.

Patients who received adequate induction therapy with 8 doses of rituximab either as first line treatment or as treatment for relapsed disease and who achieved at least a partial (PR) or complete remission (CR) after a rituximab containing induction therapy are subsequently treated with rituximab maintenance therapy. The rituximab maintenance therapy is given at the standard dose for FL (375 mg/m²) every 8 weeks for a maximum of 2 years. Rituximab was administered as Rapid-Infusion in centers which use this schedule of administration as standard.

Enrolment was completed by 31st March 2008. Of 557 screened patients 545 patients with FL were enrolled. Median age of the patients was 57 years (range 29 to 86 years), and 11.6% of the patients were older than 70 years. The FLIPI-score was 0=40/230 patients (before/after induction); 1=110/185; 2=190/72; 3=120/25;4=40/10 and 10/2. 72.8% were first-line patients and 5.1% had >4 lines of therapy. 65.1% of the patients had an induction with 8 cycles rituximab in combination with CHOP-chemotherapy. 60.6% of patients entered the study in CR, 9.9% in CRu and 29.5% in PR. Meanwhile, 334 patients have received at least 6 rituximab infusions, and 30 patients have completed all 12 rituximab infusions. 26.2% of patients received rituximab as Rapid-Infusion at infusion 2. The percentage of patients receiving Rapid-Infusion increased during the course of the study and was 43.3% at infusion 12. The rapid infusion could be administered in less than two hours (mean 1.88 – 1.94).

Disease relapse were noted in 42 patients after a median observation time of 10.4 months. 94.5% of patients who have entered the study in CR remained in CR, while 86.3% of CRu and 83.3% of PR patients were still in remission. Laboratory abnormalities CTC 3° were observed in 22 (4.1%) and CTC 4° in 6 (1.1%) patients, respectively.

Infusion-related adverse events (AEs) occurred in 28 patients of which one was serious (SAE). 71 SAEs have been reported in the 59 patients who received at least one infusion. Four SAEs were reported as rituximab-related.

These results indicate that rituximab maintenance therapy after rituximab containing induction therapy can be safely administered. It is safe irrespective of a fast infusion protocol. Only a minority of patients experience laboratory abnormalities and disease progression remains a rare event.

An update of the data will be presented.

Rowe:Teva Pharmaceuticals: Consultancy; EpiCept Corporation: Consultancy. Vranowsky:Roche: Honoraria. Hipp:Roche: Employment. Oertel:Roche: Employment.