A randomized, double-blind, three-arm, parallel group, single-dose phase I study to evaluate the pharmacokinetic similarity between SB12 (a proposed eculizumab biosimilar) and eculizumab (Soliris) in healthy subjects.

To compare the pharmacokinetics (PK), pharmacodynamics (PD), safety, and immunogenicity between SB12 (a proposed eculizumab biosimilar) and the reference product (RP) eculizumab (i.e., European Union (EU)-sourced Soliris and United States (US)-sourced Soliris). In this phase I study, healthy adult subjects were randomized to receive a 300-mg dose of SB12 or RP eculizumab via intravenous infusion. The PK endpoints were area under the serum concentration-time curve from time zero to infinity and to the last quantifiable concentration, and maximum serum concentration. Bioequivalence for the PK endpoints was determined if the 90% confidence intervals (CIs) for the ratio of geometric least squared means (Lsmeans) were within the pre-defined bioequivalence margins of 80.00 - 125.00%. PD, safety, and immunogenicity were also investigated. The 90% CIs of the geometric Lsmeans ratios of the PK endpoints were fully contained within the pre-defined bioequivalence margin. PD profiles and incidence of treatment-emergent adverse events across treatment groups were comparable. Incidence of anti-drug antibodies was also comparable between all groups, and a positive result for neutralizing antibodies was not detected. This study demonstrated PK bioequivalence and similar PD, safety, and immunogenicity profiles of SB12 to both reference eculizumab products.