Predetermined inclusion and exclusion criteria

Due to the amount of testing required for this work, appropriate animal model performance and technical bias avoidance were pursued by predetermining the following inclusion/exclusion criteria derived from prior experimental work^18,25 instead of using sham groups: (1) threshold for the absence/presence of model-induced hypersensitivity: animals with von Frey values ≤5 on the day of the first dosing were excluded since rats can reach this response level in basal conditions and (2) pain model performance: if the average von Frey values of vehicle-treated rats decreased by 50% or more during the first week following injection, then the entire tested cohort (vehicle- plus decoy-treated animals) was excluded. When they occurred, exclusions are listed in the figure legends, and the number of animals listed per testing conditions reflects the exclusions.