Module 9 2021

22/03/2021

ASSAY SENSITIVITY

% A C R

Testing on the flat part of the dose response curve shows nothing

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R E S P O N D E R S

Infliximab in rheumatoid arthritis (ATTRACT trial)

22.3.2021

55

CHALLENGES IN CONDUCTING THERAPEUTIC EQUIVALENCE TRIALS WITH BIOSIMILARS If relatively small effect impractically large trial needed. Unethical not to use new therapies added to standard treatment regimens that may drown out the effect of the test medication Target population decline as treatments become more and more personalized. Dose is often on flat part of dose response curve; in vitro testing much more sensitive indicator of difference In RA rituximab at half dose (2 X 500 mg) comparable to standard dose (2 X 1000 mg) at six months (doses 2 weeks apart) Ref 1 Siphoning patients away from trials of novel therapies

Ref 1: Chatzidionysiou K, et. al: “Effectiveness Of Two Different Doses Of Rituximab For The Treatment Of Rheumatoid Arthritis in an International Cohort: Data From the CERERRA Collaboration.” Arthritis Research and Therapy. 18;5 0;2016. https://arthritis-research.biomedcentral.com/articles/10.1186/s13075-016-0951-z. Accessed 15 April 2019.

EU Full Deck 06-Sep-2019 All Sections

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