Induction with Fludarabine, Cyclophosphamide and Rituximab Followed by Maintenance with Rituximab: Results of a Prospective Study in 75 Patients (LNHF-03).

Objectives. To evaluate clinical efficacy, molecular response and safety following the use of a regimen of fludarabine (25 mg/m2 x 3 days) Cy (1g/m2 x 1 day) and Rituximab (375 mg/m2/ x 1 day) (FCR)x 6 cycles, followed by maintenance with rituximab (375 mg/m2/week/x 4 weeks every 6 months x 2 years). (LNHF-03 Study).

Patients and methods. Seventy-five (75) patients with a diagnosis of follicular NHL were included in the study between October 2004 and January 2006. The median age was 54 years (30–75). Twenty-one per cent (21%) of the patients had bulky disease. According to the FLIPI index: (0–1): 22.6%; 2: 40,3%; 3: 37,1%. Minimal residual disease (MRD): A clonal population on diagnosis was identified by means of the bcl–2/IgH major and minor rearrangement study by means of quantitative PCR rearrangements of the Igs by means of fluorescent PCR. Subsequently, samples were studied following the induction treatment and during the maintenance treatment. The analysis is performed in the 70 patients that completed the six induction regimens and were evaluated.

Results. 64/70 patients were given the six cycles planned (91%). The presence of persistent cytopenia limited the cycles given in the other 6 patients to 4 or 5. Three hundred and thirty-eight (338) adverse effects were documented in the 414 cycles given to the 70 patients evaluated, almost all of them being mild, and 26 severe (degree 3–4), and almost all the cases were neutropenias. Infectious complications were frequent and many were severe: herpes zoster (5), pneumonia (5), cerebral toxoplasmosis (1), aspergillosis (1), infection by CMV (2). One patient developed erythroleukaemia within the first year following completion of the treatment. Three patients died ( CMV + aspergillosis, pneumonia, erythroleukaemia). 86% of the patients reached CR following induction, 6% unconfirmed CR and 8% partial response. On diagnosis, a clonal population was identified in 63% (45/71) of the cases. Of these 45 patients, samples are available following induction treatment in 35 cases. The molecular disease was negativised in all the cases, except one case with persistence of positive bcl2/IgH (0.3% as opposed to diagnosis) and is in uncertain CR. Of the 34 cases with negative ER, 32 are in CR or uncertain CR and 2 PR.

Conclusions. The FCR regimen has proven to have a potent antitumoral activity in recently diagnosed follicular lymphoma patients with very high clinical (86% CR) and molecular (95%) responses. The immunosuppression caused is profound, with the appearance of opportunistic infections, and in some cases prolonged lymphopenias and neutropenias that call for future assessment and follow-up.