Background: PB006 (Polpharma Biologics S.A; marketed as Tyruko®, Sandoz) is an approved biosimilar to natalizumab (Tysabri®; Biogen [ref-NTZ]). This multicenter, double-blind, randomized, single-dose study was conducted to demonstrate pharmacokinetic/pharmacodynamic (PK/PD) similarity between PB006 and ref-NTZ.
Research design and methods: Healthy participants (N = 453) were randomized to receive 3 mg/kg infusion of PB006, US-licensed, or EU-approved ref-NTZ before an 85-day follow-up. Primary PK endpoint was total natalizumab serum concentration over time; secondary PK endpoints explored concentration changes. Primary PD endpoints compared CD19+ cell counts and percentage α4-integrin receptor saturation, per natalizumab's mechanism of action. Secondary PD endpoints explored serum changes in sVCAM-1 and sMAdCAM-1, CD34+, and CD19+ cells. Safety, tolerability, and immunogenicity were assessed.
Results: The primary PK endpoint was met, with 90% confidence intervals (CIs) of the geometric mean for serum test/reference ratios contained within a prespecified margin (0.8-1.25). All primary PD endpoints were met, with 90% and 95% CIs within this similarity margin for baseline-adjusted CD19+ cell counts and percentage α4-integrin receptor saturation. All secondary endpoints were similarly contained, except sVCAM. No notable differences in safety, tolerability, or immunogenicity were observed.
Conclusion: Similarity was confirmed, with PB006 demonstrating PK/PD behavior consistent with that of ref-NTZ.
Clinical trial registration: EudraCT number 2019-003874-15.
Keywords: Alpha 4 integrin; biosimilar; natalizumab; pharmacodynamic; pharmacokinetic; relapsing-remitting multiple sclerosis.
PB006 (developed by Polpharma Biologics S.A; and marketed as Tyruko® by Sandoz) is an approved biosimilar to the reference medicine, natalizumab (Tysabri®, Biogen [ref-NTZ]) used to treat relapsing forms of multiple sclerosis. Approved biosimilar medicines have been shown to be as safe and effective as their reference medicines via different types of comparisons to the reference medicine, confirming that physicians and patients can expect the same clinical outcome.This study was conducted to confirm that PB006 acts the same way in the body as ref-NTZ. Healthy participants received one dose of either PB006, ref-NTZ from the US or ref-NTZ from Europe. During the study, blood samples were tested to confirm how much of each medicine was present in participants’ blood, as well as to assess changes in immune cells or proteins related to how natalizumab works. The study also measured whether any treatment caused unwanted side effects or caused any changes in the immune system that may stop the medicine working.The results showed that PB006 behaved in the same way as ref-NTZ in the blood. All reported side effects were similar between groups and were as expected for this medicine, and neither PB006 nor ref-NTZ caused any important or unexpected changes to the immune system. This study showed that biosimilar natalizumab, PB006, behaves in the same way as ref-NTZ, and the same treatment outcomes can be expected.