The Addition of Rituximab to CVP (Bagley) + Interferon-α as Induction Regimen, Significantly Increases Complete Remission Rates and Progression Free Survival In Intermediate-High Risk Follicular Lymphoma Patients (LNH-pro vs. LNH-pro-05 trial)

Abstract 2867 Introduction. Survival of Follicular Lymphoma patients has significantly increased with the introduction of immunomodulatory agents, such as Interferon (IFN) and Rituximab (R). Until 2002 our Follicular Lymphoma patients were included in a trial and received induction therapy with CVP + Interferon (LNH-pro, JCO 16; 1538–1546). Since 2006, Rituximab is being added to the same induction regimen (LNH-pro-05, EHA 09). Herein we communicate the comparative results between these two trials in Intermediate-High risk Follicular Lymphoma patients. Aim. To compare toxicity and efficacy in terms of complete remission (CR) and Progression Free Survival (PFS) between both trials in Intermediate-High risk Follicular Lymphoma patients. Methods. Patients in the LNH-pro trial (1990-2006) received CVP (CY 400mg/m2 p.o D1-5, VCR 1.4mg/m2 iv D1, PRD 100mg/m2 po D1-5) + IFN (3MU/m2 sc, 3 times/wk, for 12 wks). When it became available, G-CSF support was permited. In the LNH-pro-05 trial (2006-ongoing), Rituximab (R: 375mg/m2 iv D1) was added to the same induction regimen. All patients received 8 cycles as per protocol, with G-CSF support and Pn. jiroveci prophilaxis. In both studies, complete re-assessment was performed after cycle 4, at the end of induction therapy, every 4 months for the first 2 years and every 6 months thereafter. Results. We analysed data from 74 and 36 FL patients with FLIPI≥2, included in the LNH-pro and LNH-pro-05 trials, respectively. Patients' characteristics are shown in table 1. No significant differences were found between groups, except for a higher incidence of elevated B2-microglobulin in patients treated with CVP+IFN and higher Bulky disease (>7cm) among patients with R+CVP+IFN. Median number number of cycles were 6 and 8, respectively. Response: Seventy one patients (96%) in the LNH-pro Trial (CVP+IFN) were evaluable for response. Overall Response (OR) rate was 87%, with 68% Complete Remission (CR) and 19% Partial Remission (PR) (9% non-responders). In the LNH-pro-05 Trial (R+CVP+IFN), 36 patients (92%) and 33 patients (83%) were evaluable for response after 4th and 8th cycle. At cycle 4, all assesed patients achieved remission (15% PRs and 85% CR+uCR), while after the 8th cycle 100% of patients are in CR or uCR. Toxicity. Main hematologic grade 3–4 toxicity was neutropenia, 33% for CVP+IFN and 28% for R+CVP+IFN, with 12% and 6% of infections, respectively. Other non-hematologic toxicities were infrequent and mild (5% and 10% in each group). Eight percent of patients in the LNH-pro trial withdrew treatment due to toxicity. At the moment, none of the patients in the LNH-pro-05 trial have experienced an unacceptable toxicity. Survival . Median follow-up was 7.7 years for CVP+IFN and 2 years for R+CVP+IFN. A significant increase of PFS was seen among patients who received R (66% vs. 86%, at 3 years, P 0.05). There is also a trend to a longer overall survival in patients treated with R+CVP+IFN (P 0.07). Conclusion. The addition of Rituximab to CVP+IFN induction regimen in Intermediate-High risk Follicular Lympoma patients, significantly increases complete remission rates (88% to 100%) and progression free survival (86%, at 3 years), with a low toxicity profile. Disclosure: No relevant conflicts of interest to declare.