Background In 2009, lenalidomide was included in our hospital formulary for the treatment of multiple myeloma (MM). Presently, real world data are fundamental in the evaluation of drugs.

Purpose To assess the effectiveness and safety of lenalidomide for MM in clinical practice in a university hospital.

Material and methods We carried out a retrospective, longitudinal, observational study which included all patients treated with lenalidomide for MM between January 2015 and August 2015.

Variables were collected from medical records and laboratory tests: demographics, pharmacotherapeutics (starting date of lenalidomide, dose adjustment and reasons, therapy duration and reasons for discontinuations, and adverse events) and analyticals (paraprotein level, calcaemia, and neutrophil and platelet levels).

Effectiveness was assessed using the increase in paraprotein level (> 0.5g/dL) and in calcaemia (>11.5 mg/dL). Safety was evaluated by the incidence of reported adverse events (AEs).

Results 52 patients with a median age (p25, p75) of 71.5 years (61.2, 79.0) were included. Median duration of treatment with lenalidomide was 37.3 weeks (12.0, 68.6). Paraprotein levels decreased in 23 patients (44.2%), while in 24 patients (46.2%) they remained constant. Hypercalcaemia (>11.5 mg/dL) was not reached in any patient. During the study period, 17 patients (32.7%) discontinued lenalidomide: 5 patients (9.6%) due to progression (increase >0.5 g/dL in paraprotein level), 4 patients (7.7%) due to complete response after 2 years of treatment, 4 patients (7.7%) due to pancytopenia and 4 patients (7.7%) for other reasons.

The observed AEs included asthenia (38.5%), neutropenia (36.5%), itchiness (21.2%), constipation (13.5%), thrombocytopenia (11.6%), diarrhoea (9.6%), urinary tract infection (3.8%) and thromboembolism (1.9%). Dose adjustment was necessary in 25 patients (48.1%) to manage neutropenia and thrombocytopenia related to lenalidomide.

Conclusion In 90.4% of patients lenalidomide seemed to control the disease. The most common AE was haematological disorder. This should be closely monitored as it led to a dose reduction or cessation in more than half of the patients.

No conflict of interest.