Addition of rituximab to fludarabine and cyclophosphamide in patients with chronic lymphocytic leukaemia: a randomised, open-label, phase 3 trial

BACKGROUND

On the basis of promising results that were reported in several phase 2 trials, we investigated whether the addition of the monoclonal antibody rituximab to first-line chemotherapy with fludarabine and cyclophosphamide would improve the outcome of patients with chronic lymphocytic leukaemia.

METHODS

Treatment-naive, physically fit patients (aged 30-81 years) with CD20-positive chronic lymphocytic leukaemia were randomly assigned in a one-to-one ratio to receive six courses of intravenous fludarabine (25 mg/m(2) per day) and cyclophosphamide (250 mg/m(2) per day) for the first 3 days of each 28-day treatment course with or without rituximab (375 mg/m(2) on day 0 of first course, and 500 mg/m(2) on day 1 of second to sixth courses) in 190 centres in 11 countries. Investigators and patients were not masked to the computer-generated treatment assignment. The primary endpoint was progression-free survival (PFS). Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00281918.

FINDINGS

408 patients were assigned to fludarabine, cyclophosphamide, and rituximab (chemoimmunotherapy group) and 409 to fludarabine and cyclophosphamide (chemotherapy group); all patients were analysed. At 3 years after randomisation, 65% of patients in the chemoimmunotherapy group were free of progression compared with 45% in the chemotherapy group (hazard ratio 0·56 [95% CI 0·46-0·69], p<0·0001); 87% were alive versus 83%, respectively (0·67 [0·48-0·92]; p=0·01). Chemoimmunotherapy was more frequently associated with grade 3 and 4 neutropenia (136 [34%] of 404 vs 83 [21%] of 396; p<0·0001) and leucocytopenia (97 [24%] vs 48 [12%]; p<0·0001). Other side-effects, including severe infections, were not increased. There were eight (2%) treatment-related deaths in the chemoimmunotherapy group compared with ten (3%) in the chemotherapy group.

INTERPRETATION

Chemoimmunotherapy with fludarabine, cyclophosphamide, and rituximab improves progression-free survival and overall survival in patients with chronic lymphocytic leukaemia. Moreover, the results suggest that the choice of a specific first-line treatment changes the natural course of chronic lymphocytic leukaemia.

FUNDING

F Hoffmann-La Roche.

Health related quality of life (HRQOL) evaluated with the EORTC C30 questionnaire in first line therapy of elderly patients with chronic lymphocytic leukemia (CLL): Results of a phase III trial of the German CLL Study Group (GCLLSG)

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Background: The GCLLSG evaluated the efficacy of fludarabine (F) versus (vs.) chlorambucil (Clb) in first line therapy of older patients with advanced CLL. HRQOL was evluated by using the EORTC C30 questionnaire. Methods: Pts were randomized to receive 6 courses of F (25 mg/m²/day (d) IV for 5d; 92 pts) or 12 months (mo) of Clb (0.4–0.8 mg/kg/d PO, every 15d; 99 pts). All pts were previously untreated, aged between 65 and 79 years and in advanced stage Binet C or symptomatic Binet B or A. Primary endpoints were overall survival (OS) and progression free survival (PFS), secondary endpoint was HRQOL. The EORTC C30 questionnaire (version 2.0) was sent to all patients at baseline and after 6, 12 and 24 mo. Scores (0–100) for 15 different measures (1 global HRQOL, 5 functional, 3 symptom and 6 single item scales) were evaluated at each time point. Results: F induced significantly higher response rates and prolonged the PFS, while no significant difference in OS was observed. At baseline 130 of 191 pts (68%) completed the questionnaires followed by more than 80% at mo 6 to 24. Compliance rates were similar in both treatment arms. Between pts completing questionnaires or not no statistically significant differences in perfomance status, age, stage or response to treatment were observed. HRQOL differences in comparison to baseline values were significantly improved after F treatment in global HRQOL, role and social functioning after 12 months as shown by the table. Responders had a significantly better global HRQOL and social functioning as well. Except for an impaired physical functioning no differences in HRQOL were observed between different age groups (65–69, 70–74, 75–79). Conclusion: Elderly F treated patients with CLL showed improvement inglobal HRQOL. Elderly age groups had a similar HRQOL as younger age groups.

[Table: see text]

[Table: see text]

Advances in chemotherapy for chronic lymphocytic leukemia

While chemotherapy based on alkylating agents has been the standard treatment of chronic lymphocytic leukemia (CLL) for decades, purine analogues and their combinations have emerged as effective new therapies for previously untreated and pretreated patients. As single agents, fludarabine and cladribine are the most promising, showing higher remission rates compared to chlorambucil. For younger and physically fit patients, the combination of fludarabine and cyclophosphamide has shown benefit. Fludarabine plus epirubicin appears equally potent. The addition of monoclonal antibodies, such as rituximab and alemtuzumab, to purine analogues alone or in combination seems to be even more effective for chemotherapy-naive and pretreated CLL patients. Another promising agent in the armamentarium of therapies for CLL is bendamustine, which has properties of both an alkylating agent and a purine analogue. Clinical trials are ongoing with novel drugs that interfere with cell cycle regulation and signaling molecules in CLL, including flavopiridol, UCN-01, bryostatin 1, depsipeptide, and oblimersen. It remains to be seen whether these chemotherapeutic approaches offer real benefit for patients by prolonging survival with an improved quality of life.