PB2131 CTDA VERSUS MPT FOR MULTIPLE MYELOMA: REAL WORLD DATA FROM THE WEST OF SCOTLAND CANCER NETWORK

Background: Multiple myeloma has a median age at presentation of approximately 70 years and many patients are unsuitable for intensive induction chemotherapy and autologous stem cell transplant due to advanced age or co‐morbidity. Current West of Scotland Cancer Network, BCSH and NICE Clinical Management Guidelines supports the use of either CTDa (attenuated Cyclophosphamide, Thalidomide and Dexamethasone) or MPT (Melphalan, Prednisolone, Thalidomide) as options for first line treatment in patients ineligible for high dose therapy. Despite these recommendations there are little reported data directly comparing the efficacy of these two commonly used chemotherapy regimens. Aims: In order to determine whether the choice of either CTDa or MPT as first line therapy had any influence on survival among our patient population, we retrospectively analysed real‐world data from patients treated initially with either CTDa or MPT in the West of Scotland Cancer Network between 1/1/2013 and 1/1/2016. Methods Patient data including demographics, details of treatment regimens, ECOG performance status, ISS and renal function at diagnosis were extracted, where available, from electronic prescribing records and electronic notes. Individual patient mortality data was collected for 6 years from initiation of their treatment. All data were analysed using “R” software (v3.5.2). Results: In total 171 patients were treated with either CTDa (n = 126) or MPT (n = 45) first line for multiple myeloma between 1/1/13 and 1/1/2016. Patients received a similar number of cycles (median 6 CTDa vs 5 MPT). Mean age for patients treated with CTDa was 74 (72.8‐75.2) and MPT 76.9 (75.4‐78.4), male to female ratio was 1:1.06 for CTDa and 1:1.8 for MPT. Kaplan Meier curves were constructed and compared using the logrank test. Median survival was 1258 days for CTDa and 785 days in the MPT group. Although the Kaplan Meier curves appeared to show some benefit to probability of survival in favour of CTDa, there was no statistically significant difference between the Kaplan Meier curves (p = 0.15). Due to the retrospective nature of our data collection we were unable to provide details of response rate or progression free survival. Summary/Conclusion: Our data show comparable survival between patients treated with CTDa or MPT in an unselected patient population. Our results are similar to those reported in the prospective UK Myeloma IX trial 1 . It should be noted that patients treated with both CTDa and MPT in our dataset had extensive modifications to their treatment regimen diverging from the established protocol. Most frequently patients treated with CTDa received once weekly Dexamethasone instead of four‐day steroid pulses, as reflects common clinical practice in frail or elderly patients. However, it was reassuring to note that regimen modification did not appear to adversely affect OS when compared to published data.Acknowledgement: The authors are grateful to Christine Crearie and colleagues in the West of Scotland Cancer Network and West of Scotland Haematology Audit Group for support and access to patient data.