Romiplostim for chemotherapy induced thrombocytopenia in solid tumors: A meta-analysis.

e24137 Background: Chemotherapy-induced thrombocytopenia (CIT), defined as platelets < 100,000/mcL persisting for ≥3-4 weeks post-chemotherapy affects 20-25% of cases necessitating platelet transfusions or dose reductions leading to treatment delays and impacting patient outcomes. (1,2) Despite multiple studied agents, there are no established guidelines. Romiplostim, a thrombopoietin receptor agonist approved for immune thrombocytopenic purpura, stands out. NCCN suggests its use, but pooled analyses are lacking. Our meta-analysis addresses this gap, exploring romiplostim's efficacy in CIT management. Methods: We performed a systematic search of PUBMED, EMBASE, and COCHRANE databases for studies that evaluate the use of romiplostim in the setting of CIT for solid tumors. The primary endpoint was the proportion of patients that showed improvement in platelet counts in response to romiplostim. Secondary endpoints were the proportion of patients that continued full dose chemotherapy dose on romiplostim and incidence of thromboembolic events. Pooled proportions were calculated along with 95% confidence intervals (CI) using a random-effects model. I2 statistic was used to depict inter-study heterogeneity. Results: A total of 10 single arm studies - 3 prospective studies, 3 case series, and 4 retrospective studies were included. The pooled outcomes were: significant improvement of platelet count above 100K with response to romiplostim therapy in 80.53% patients 95 % CI 72.47 - 87.48, I2 = 69%, proportion of patients that continued full dose chemotherapy on romiplostim was 70.89% 95% CI 63.40 - 77.84, I2 = 0%, and incidence of thromboembolic events was 6.81% 95% CI 3.64 – 10.89, I2 = 35%. Variables like platelet transfusions, bleeding events, type and stage of cancer were not reported uniformly and hence subgroup analyses could not be performed. Conclusions: Our analysis reveals that romiplostim improved the platelet counts in majority of patients with underlying CIT associated with solid tumors. It also shows that a majority of the patients were able to resume their full dose chemotherapy when maintained on romiplostim. The incidence rate of thromboembolic events with romiplostim believed to be consistent with what expected of this population with majority having advanced/high-risk malignancies. Given its efficacy, romiplostim may be used for routinely managing CIT in solid tumors. This analysis is limited by lack of comparative studies and warrant further randomized trials to confirm the safety and efficacy of romiplostim in this patient population.