Similar PK, Safety, and Immunogenicity Demonstrated for Proposed Bevacizumab Biosimilar

During the American Society of Clinical Oncology’s Annual Meeting, held June 1-5 in Chicago, Illinois, researchers presented results from a phase 1, randomized study that sought to evaluate the pharmacokinetic (PK) equivalence of a potential bevacizumab biosimilar with the originator product.

The proposed biosimilar, TAB008, under development by TOT Biopharm, was compared with the reference bevacizumab in a randomized, double-blind, single-dose study conducted in 99 healthy adult males.

Study participants were aged 18 to 45 years and were randomized to receive 1 mg/kg of TAB008 (n = 49) or reference bevacizumab (n = 50) over a 90-minute infusion. Participants were followed for 99 days post-infusion.

The study had 3 primary endpoints: area under the serum concentration—time curve from time 0 to time of last quantifiable concentration (AUC_0-t)_, AUC from time 0 extrapolated to infinity (AUC_0-∞), and the maximum observed serum concentration (C_max). In addition, the study also evaluated the safety and immunogenicity of the potential biosimilar compared with the originator as secondary endpoints.

The treatment-group ratios of least squares geometric means for the 3 primary pharmacokinetic parameters were fully contained within the prespecified bioequivalence limits of 80% to 125% (90% CI, 103.66%-118.33% for C_max; 94.32%-111.72% for AUC_0-t; and 94.69%-112.23% for AUC_0-∞).

Treatment-emergent adverse events (TEAEs) were reported in 25 participants (51%) in the TAB008 group and 22 (44%) subjects in the reference bevacizumab group. Drug-related TEAEs were reported in 19 (38%) of subjects in both groups.

National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE) grade 3 TEAEs were demonstrated in 1 (2%) participant in the TAB008 arm, and 3 (6%) participants in the reference bevacizumab arm. However, no adverse events led to an individual’s discontinuation of participation in the study. In addition, the authors noted that no study participant developed binding or neutralizing anti-drug antibodies to the proposed biosimilar.

Researchers found that the proposed biosimilar demonstrated pharmacokinetic similarity to the reference product, and the safety and tolerability of the 2 products were also comparable.

Reference

Liu J, Wang X, Wang J, et al. A phase 1, randomized, single-dose study evaluating the pharmacokinetic equivalence of TAB008 and bevacizumab in healthy volunteers. J Clin Oncol. 2018;36(suppl; Abstract e14504).