A real-world comparative analysis of pomalidomide (POM) and other antimyeloma treatments following lenalidomide (LEN) discontinuation among patients with multiple myeloma.

Abstract

e19337 Background: In clinical trials, POM has demonstrated favorable clinical outcomes in patients with multiple myeloma (MM) who received prior LEN. Few studies, however, have examined POM treatment for MM in the community oncology setting. This retrospective cohort study compared treatment patterns and outcomes between patients who received a post-LEN treatment, either POM or another antimyeloma regimen. Methods: Adult patients with MM in the US Oncology Network (USON) who initiated a post-LEN treatment within 60 days of LEN discontinuation between Jan 1, 2016 and May 1, 2018, were not clinical trial participants, and had ≥ 2 subsequent clinic visits, were eligible. Data were sourced from USON’s iKnowMed electronic health records. Among patients observed to have discontinued treatment, time to treatment discontinuation (TTTD) was estimated from date of initiation of post-LEN treatment (index treatment) to date of discontinuation. Among patients who started a new treatment after the index treatment, time to next treatment (TTNT) was estimated from date of initiation of index treatment until date of initiation of the next treatment. TTTD and TTNT were analyzed using the Kaplan–Meier (KM) method across the whole study sample; patients who did not discontinue or start a next treatment were censored. Results: Of 547 eligible patients, 155 (28.3%) initiated POM and 392 (71.7%) initiated another antimyeloma regimen. Demographic characteristics were similar between the groups (for all patients, median age was 68 years, 54.5% patients were male and 71.7% were white). In total, 74.2% and 83.7% of patients discontinued the index treatment in the POM and other-treatment groups, respectively. Among the entire study population, KM estimates of median TTTD were 3.5 months (95% CI 2.8–4.6) and 1.9 months (95% CI 1.6–2.4) in the POM and other-treatment group, respectively (log-rank P < 0.001). In total, 65.2% and 71.2% of patients initiated subsequent treatment in the POM and other-treatment groups, respectively. KM estimates of median TTNT were 6.2 months (95% CI 4.5–7.8) and 4.5 months (95% CI 3.9–5.3) in the POM and other-treatment groups, respectively (log-rank P = 0.38). Conclusions: For patients with MM the use of POM following LEN treatment resulted in longer TTNT and TTTD compared with those who received other antimyeloma therapy. These findings support the use of POM treatment after LEN as an option for patients with relapsed/refractory MM.