1732 - Safety and efficacy of Bendamustine and Rituximab (BR) regimen in Indian Chronic Lymphocytic Leukemia patients

Background

We investigated the safety and efficacy of bendamustine-rituximab (BR) in previously untreated symptomatic and advanced CLL patients, as there is no data available on BR from Indian subcontinent.

Methods

This retrospective study included 120 consecutive treatment naïve patients with CLL without del (17p), who were registered at Department of Medical Oncology, AIIMS between January 2010 and to July 2018. Bendamustine was given at a dose of 90 mg/m²on day 1 and 2, combined with rituximab 375 mg/m² rituximab on day 1, every 28 days for up to 6 courses. Event free survival (EFS) was defined as date of treatment to date of relapse, disease progression or death due to any cause.

Results

The median age was 57 years (range: 30-75 years). As per clinical Rai stage 30(25%) patients were in stage II, 42(35%) were in stage III and 48(40%)were in stage IV. ZAP-70 was positive (>20%) in 50%, CD 38 was positive (>30%) in 33%, and CD49d was positive (>30%) in 49% of cases. Beta-2 microglobulin (B2M) was elevated (≥3.5 mg/L) in 80% of cases. Fifty five cases (50%, n = 110) were IGHV mutated. The mean number of cycles was 5 (1-6). Overall response rate (ORR) seen with BR was 90% and complete response was 45%. Median event free survival was 24 months with a median follow up period of 29 months. Haemoglobin (<10g/dL), elevated B2 M, unmutated IGHV had statistically significant adverse impact on EFS on univariate analysis but on multivariate analysis only IGHV mutation status was found to had significance on EFS. The median EFS was 27 months in IGVH mutaed vs 18 months in IGHV unmutated-CLL patients (p = 0.001). Grade III/IV neutropenia, thrombocytopenia, anaemia and infections were observed in 12%, 8%, 7.5% and 10% respectively. The most common non -haematological toxicity was skin rash which was observed grade I/II in 24 cases ( 20%) and grade III/IV in 12 cases (10%).

Conclusions

This is the first study of Asia to demonstrate safety and efficacy of BR in symptomatic CLL patients. BR is effective and safe regimen in the first-line treatment of CLL. Unmutaed- CLL patients have inferior EFS than mutated - CLL patients. Skin toxicity was the most common adverse effect seen in our population which was observed in around one third of cases.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.