[A prospective multi-center trial of non-interventional and observational study of lenalidomide in Chinese patients...

Objective: To evaluate the efficacy and safety of lenalidomide in a real-world clinical practice in Chinese patients with multiple myeloma (MM). Methods: It was a prospective, multi-center, observational study. A total of 165 consecutive patients with MM treated with lenalidomide-based regimens were enrolled in 12 hospitals from June 2013 to November 2015. Relevant information was recorded, such as baseline clinical data, cytogenetic abnormalities, treatment regimens, and duration of treatment, safety, and survival. Results: (1)There were 126 relapsed and refractory MM (RRMM) patients, 25 newly diagnosed patients and 19 maintenance patients. The evaluable RRMM patients accounted for 120 cases, among which 74 cases(61.7%) reached the partial response (PR) or above, and a very good partial response (VGPR) in 16 patients (13.3%), a complete response (CR) in 14 cases (11.7%), a strictly complete response (sCR) in 4 cases (3.3%). Thus, a VGPR or above in 34 patients accounted for 28.3%. (2)The median follow-up was 13 months, the median time to progression 12 months. The median survival after receiving lenalidomide was 19 months, and the median overall survival (OS) was 62 months. (3) The univariate analysis in 120 RRMM patients suggested that prognostic factors for significant improvement in PFS included normal karyotype, international staging system (ISS) Ⅰ-Ⅱ, t(4; 14) negative (detected by fluorescence in situ hybridization), non-bortezomib resistance and response to previous regimens. As to OS, non-bortezomib resistance, response to previous regimens and non-primary refractoriness were positive factors. Multivariate analysis showed that the response to previous regimens (PR or better) was an independent good prognostic factor for progress-free survival(PFS), non-bortezomib resistance and non-primary refractoriness for OS. (4) Grade 3 or 4 adverse events that occurred in more than 10% of all enrolled patients were neutropenia (12.7%), leukocytosis(11.5%) and thrombocytopenia (12.7%). Owing to intolerance of toxic side effects, 7 cases withdrew lenalidomide. Conclusions: No matter what combination, regimens containing lenalidomide are effective to RRMM patients with overall response rate 61.7%, a time to progression 12 months and an overall survival 62 months.The toxicity is quite tolerable and manageable. In addition, the response to previous treatment (reached PR or above) is the independent good prognostic factor for PFS, non-bortezomib resistance and non-primary refractoriness for OS. Clinical trail registration: Clinicaltrials.gov, NCT01947309.