In a single-center phase II study reported in the Journal of Clinical Oncology, Soff et al found that treatment with romiplostim was effective in rapidly correcting chemotherapy-induced thrombocytopenia, with maintenance treatment being effective in reducing risk of recurrent chemotherapy-induced thrombocytopenia.
Study Details
The trial was conducted at Memorial Sloan Kettering Cancer Center and included 23 patients with chemotherapy-induced thrombocytopenia with platelets < 100,000/mL for at least 4 weeks despite delay or dose reduction of chemotherapy. Mean platelet count at enrollment was 62,000/mL.
Patients were randomly assigned 2:1 to receive weekly titrated romiplostim with a target platelet count of ≥ 100,000/mL (n = 15) or monitoring with usual care (n = 8). An additional 37 patients with chemotherapy-induced thrombocytopenia received romiplostim in a single-arm romiplostim phase. The primary outcome measure was correction of platelet count within 3 weeks.
Platelet Count Correction
KEY POINTS
- Overall, romiplostim treatment resulted in correction of platelet counts by 3 weeks in 85% of patients with chemotherapy-induced thrombocytopenia.
- A recurrence of chemotherapy reduction or delay due to chemotherapy-induced thrombocytopenia was observed in 7% of patients.
In the randomized phase, 14 (93%) of 15 patients receiving romiplostim had correction of platelet count within 3 weeks vs 1 (12.5%) of 8 patients in the control group (P < .001). Among all 52 patients receiving romiplostim, mean platelet count at 2 weeks was 141,000/mL, compared with a mean count of 57,000/mL at 3 weeks among patients in the control group. Corrected platelet counts were achieved in 44 (85%) of the 52 patients within 3 weeks. Among the 44 patients who had correction of platelet count with romiplostim and resumed chemotherapy with weekly maintenance romiplostim, 3 (6.8%) had subsequent reduction or delay in chemotherapy due to chemotherapy-induced thrombocytopenia.
The investigators concluded: “This prospective trial evaluated treatment of chemotherapy-induced thrombocytopenia with romiplostim. Romiplostim is effective in correcting chemotherapy-induced thrombocytopenia, and maintenance allows for resumption of chemotherapy without recurrence of chemotherapy-induced thrombocytopenia in most patients.”
Gerald A. Soff, MD, of the Hematology Service at Memorial Sloan Kettering Cancer Center, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was supported by Amgen and by a grant from the National Cancer Institute. For full disclosures of the study authors, visit jco.ascopubs.org.
