REAL-WORLD ITALIAN EXPERIENCE OF POMALIDOMIDE IN RELAPSED-REFRACTORY MYELOMA: RETROSPECTIVE MULTICENTER STUDY BY THE RETE EMATOLOGICA PUGLIESE AND BASILICATA

Background: The POM+LoDEX combination was approved for patients with RRMM who have received at least two prior therapies including lenalidomide and bortezomib. Aims: We report here retrospective analysis of 94 patients with RRMM treated with POM+LoDEX as salvage therapy at 12 hematological centers in the Puglia and Basilicata Network to describe the outcomes and toxicities in a daily practice setting outside clinical trials. Methods: From January 2016 to September 2018, 94 patients (60 F and 34 M) were treated in our haematogical Institutions. Sixty-three patients of them (67%) had relapsed MM and 31 patients (33%) MM refractory to two or more previous treatment lines. The median age was 73 years (range 42–86). Twenty-four patients (23,3%) had EMD. Patients received a median 3 previous lines of therapy. The last treatment received was bortezomib-based regimens in 29% of patients, lenalidomide-based regimens in 50% of patients, and bendamustine containing regimen in 18% of patients. Results: The median number of cycles administered was 5 (range 1–27). The ORR was 51%. Higher ORR was recorded in the patient group with relapsed MM compared to those with refractory disease (p < 0.05). There were no statistically significant differences in terms of response between patients who had received two or more previous lines of therapy (p NS) and between patients aged over or under 70 years (p 0.25). After median follow-up of 9.5 months, median TTP and median OS in the ITT population were respectively, 10 months (range 7–17) and 16 months (range 11–24). The median TTP was significantly longer in patients who achieved the haematological response (p < 0.001) and in patients aged >70 years (p 0.03). The median OS was significantly longer for fit patients (p 0.03). The “disease status’’, the “prior exposure to lenalidomide-based strategies’’, the “number of previous lines of therapy’’ did not influence the TTP and the OS. Multivariate analysis of median TTP identified the “high LDH levels’’ as negative variable (p < 0.001) and the “age >70 years’’ as positive prognostic factor (p < 0.001). Multivariate analysis of median OS identified the “frailty score’’ and confirmed “high LDH levels’’ as statistically significant variables (p < 0.001). Median TTNT was 30 months (range 18–30). Neutropenia was the most common hematologic adverse event and occurred in 32% of patients. The most frequent grade 3–4 non-haematologic toxicities were fatigue (6%) and infections (4%). Summary/Conclusion: POM+LoDEX resulted in a longer OS and TTP compared to data reported from clinical trials. This advantage was observed mainly in elderly patients and in those with haematologic response and the outcome benefit remained consistent regardless of number of prior and last therapy received. The good toxicity profile and the all-oral administration of POM+LoDEX make this combination a recommended therapeutic opportunity also in older patients and should be recommended mainly in patients living far from the hospital.