Prevalence of preexisting articular bone pathology in patients with osteoarthritis screened for fasinumab clinical trials identified by X-ray or magnetic resonance imaging.

ABSTRACT

OBJECTIVE: To examine the prevalence of preexisting articular bone pathology in patients with hip or knee pain due to osteoarthritis (OA) screened for fasinumab clinical trials. METHOD: This post-hoc analysis included patients with OA screened for three phase 3 fasinumab studies (NCT02683239, NCT03161093, NCT03304379). During screening, participants who met other clinical inclusion/exclusion criteria underwent radiography of knees, hips, and shoulders. Those with Kellgren-Lawrence grade (KLG) ≥ 2 for index joint and without an exclusionary finding proceeded to magnetic resonance imaging (MRI) of index, contralateral, and KLG ≥ 3 joints. Exclusionary findings included bone fragmentation/collapse, bone loss/resorption, osteonecrosis, and fracture, by either X-ray or MRI. Participants with extensive subchondral cysts were also excluded. Prevalence of abnormalities on radiographs and MRIs are reported. RESULTS: Of 27,633 participants screened, 21,997 proceeded to imaging. Of these, 1203 (5.5%) were excluded due to the presence of ≥ 1 joint with severe articular bone pathology (X-ray or MRI) bone fragmentation/collapse (2.60%), subchondral insufficiency fracture (SIF; 1.67%), osteonecrosis (1.11%), and significant bone loss (0.32%). Additionally, 3.13% screen-failed due to extensive subchondral cysts. More than half of the exclusions due to bone fragmentation/collapse (386/572), osteonecrosis (141/245) and significant bone loss (59/71), and approximately one third of SIF (133/367) and extensive subchondral cysts (229/689) were evident on X-rays. CONCLUSIONS: Approximately one in 20 participants with OA who met the clinical screening criteria for fasinumab phase 3 trials were later excluded due to preexisting severe articular bone pathology findings by X-ray or MRI.