Daratumumab plus bortezomib or daratumumab plus lenalidomide as salvage therapy for patients with myeloma: initial follow-up of an Italian multicentre retrospective clinical experience by ‘Rete Ematologica Pugliese’

We report herein a multicentre retrospective analysis of 192 consecutive patients with symptomatic refractory/relapsed multiple myeloma (RRMM) treated with daratumumab in combination with bortezomib or lenalidomide as salvage therapy at 9 haematological centres in Puglia. Choice of both regimens was based on previous treatment and/or physicians' preference. Considering the under-representation of older patients (very old patient >= 80 years) in clinical trials and the prognostic and predictive importance and value of frailty status, here, we further characterised the patient cohort by age. The overall response rate (ORR) was generally lower than what was previously reported in the CASTOR (ORR 72.6% vs 85%) and POLLUX (ORR 86.5% vs 93%) trials. The lower ORR in our analysis compared to the CASTOR and POLLUX trials could be related to a less selected population. Similarly, amongst very old patients, the ORR was encouraging: ORR to treatment with DVd (daratumumab + bortezomib + dexamethasone) was 66.7%, and ORR to treatment with DRd (daratumumab + lenalidomide + dexamethasone) was 92.3%. Median TTP (time to progression) was 10.8 months (1-year TTP: 44.7%; 2-year TTP: 25.3%) in the DVd group; median TTP was not reached in the DRd group (1-year TTP: 82.7%; 2-year TTP: 71.4%). Median OS (overall survival) was not reached either in the DRd group (1-year OS: 85.9%; 2-year OS: 73.7%) or the DVd group (1-year OS: 70.2%; 2-year OS: 58.9%).