A randomized study comparing the pharmacokinetics of the potential biosimilar PF-06438179/GP1111 with Remicade® (infliximab) in healthy subjects (REFLECTIONS B537-01)

<p><b>Background</b>: To demonstrate pharmacokinetic (PK) similarity of PF-06438179/GP1111, a potential biosimilar to Remicade®, to Remicade® sourced from European Union (infliximab-EU) and United States (infliximab-US), and of infliximab-EU to infliximab-US.</p> <p><b>Methods</b>: In this phase I, parallel-group, three-arm trial, healthy adult subjects were randomized to receive a single 10-mg/kg intravenous infusion of PF-06438179/GP1111, infliximab-EU, or infliximab-US. PK, and safety and immunogenicity evaluations were performed over 8 and 12 weeks, respectively. PK similarity was established if the 90% confidence intervals (CIs) of the test-to-reference ratios for PK parameters, C<sub>max</sub>, AUC<sub>T</sub>, and AUC<sub>inf</sub>, were within the 80.00–125.00% pre-specified equivalence window.</p> <p><b>Results</b>: Of 151 subjects randomized, 146 received study treatment; 130 were eligible for PK similarity assessment. Serum concentration–time profiles were similar across the three treatments. The 90% CIs for test-to-reference ratios for C<sub>max</sub>, AUC<sub>T</sub>, and AUC<sub>inf</sub> were within 80.00–125.00% for comparison of PF-06438179/GP1111 to infliximab-EU and infliximab-US, and of infliximab-EU to infliximab-US. Similar numbers of subjects across treatment groups experienced adverse events. Anti-drug and neutralizing antibody profiles were largely similar among groups.</p> <p><b>Conclusions</b>: This study demonstrated PK similarity of PF-06438179/GP1111 to infliximab-EU and infliximab-US, and of infliximab-EU to infliximab-US. All three products displayed comparable safety and immunogenicity profiles.</p> <p><b>Trial registration</b>: CT.gov identifier NCT01844804</p>