Tony Hagen is senior managing editor for The Center for Biosimilars®.
A high overall response rate of 93% was observed for patients with immune thrombocytopenic purpura who received romiplostim biosimilar.
A single-center, retrospective data analysis in India evaluating safety and efficacy of biosimilar romiplostim (Romy) in patients with immune thrombocytopenic purpura (ITP) has demonstrated a high overall response rate (93%) without adverse events.
Romiplostim (Nplate) received US approval in 2008 for the treatment of ITP, which is characterized by an immune system attack on platelets that results in bruising, bleeding, and reddish-purple spots on the lower legs. The biosimilar Romy is approved in India but not in the United States.
Investigators enrolled 54 patients (male, 23; female, 31; median age, 40 years) with steroid-refractory or steroid-dependent ITP at the Haemato-Oncology Care Center in Vadodara, India, from July 2019 to January 2020. All patients had a pretreatment platelet count of less than 30,000/cmm. Romiplostim biosimilar was administered in a dose of 1 mcg/kg to 6 mcg/kg subcutaneously once a week.
Roughly 20% of patients (n = 12) had active bleeding and also received a concomitant rituximab 100 mg infusion once weekly for 4 weeks. For 51 patients, the overall response rate (ORR) with platelet count above 50,000 cmm; 4 patients (7%) had no response. Among patients who received rituximab with romiplostim, the ORR was 100% (12).
Investigators said the time to response was 1 week in 85% (46) of patients, and 16% (9) had a sustained response lasting more than 6 months even after discontinuing romiplostim at 4 weeks of therapy. They said 40% (21) had a sustained optimum response lasting more than 6 months with uninterrupted treatment. No patients experienced serious adverse events.
“Biosimilar romiplostim has shown rapid, excellent, and sustained response in the majority of ITP patients in our study,” said Seema S. Bhatwadekar, MD, MBBS, lead study author. “Its affordable cost [$160 per month] fulfills an unmet need for ITP patients requiring the best second line of treatment in India.”
Bhatwadekar SS, Deshpande SV, Khadse SV, et al. Efficacy and safety of biosimilar romiplostim in immune thrombocytopenic purpura: single centre retrospective data analysis. Presented at: 62nd American Society of Hematology Annual Meeting and Exposition; December 5-8, 2020. Abstract 2676.