Efficacy and immunogenicity of insulin biosimilar compared to their reference products: a systematic review and meta-analysis

Background: To ascertain the efficacy, safety, and immunogenicity from existing evidence via conducting a meta-analysis of randomized controlled trials between biosimilar and originator insulins. Methods: The PubMed, Cochrane Library, EMBASE, and ClinicalTrails.gov were searched to identify head-to-head randomized controlled trials (RCTs) that directly compare the efficacy and safety of biosimilar insulin and its originator. Efficacy was assessed by change of HbA1C, fasting plasma glucose (laboratory or self-monitoring of blood glucose (SMBG)), and change all mean of 7 points- or 8 points- SMBG. Safety was assessed by change in proportion hypoglycemia and serious hypoglycemia. The occurrence of anti-insulin antibodies (AIAs) was also evaluated. Results: Fourteen RCTs with 6188 patients from different countries were included. Data were pooled using a random-effects model and were expressed as the mean difference (MD), odds ratio (OR), and 95% confidence interval (CI). In efficacy, Insulin biosimilar products showed similar in change of HbA1C at weeks 26 and 52, the MD were 0.03 (95% CI − 0.02 to 0.07, p = 0.28), and 0.05 (95% CI − 0.05 to 0.15, p = 0.36), respectively. The proportion of HbA1C less than 7% at endpoint, the OR were 1.04 (95% CI 0.89 to 1.20, p = 0.64). The change of fasting plasma glucose (laboratory or SMBG) mmol/L in 24–52 weeks and change all mean of 7 points−/8 points- SMBG mmol/L in 24–52 weeks, the MD were 0.02 (95% CI − 0.20 to 0.24, p = 0.87) and − 0.34 (95% CI − 1.35 to 0.67, p = 0.51), respectively. In occurrence of hypoglycemia (≥ 1 events) and severe hypoglycemia, the OR were 0.96 (95% CI 0.85 to 1.09, p = 0.52) and 1.06 (95% CI 0.85 to 1.31, p = 0.62). The AIA was 1.02 (95% CI 0.90 to 1.16, p = 0.76). Analysis stratified by type of diabetes and duration of insulin. There was no significant difference between the biosimilar and their reference group in a different type of diabetes and different duration of insulin. Conclusions: Insulin biosimilar showed comparable characteristics with the reference drug in terms of efficacy, safety, immunogenicity, through comprehensive and specific conventional meta-analysis.