Comparison of efficacy between triamcinolone acetonide and triamcinolone hexacetonide for intraarticular therapy in juvenile idiopathic arthritis: a retrospective analysis

Background There are many FDA-approved corticosteroid preparations available for intra-articular injection, however triamcinolone hexacetonide is not one of them. It was the intraarticular drug of choice among pediatric rheumatologists up until approximately a decade ago, when production of this medication ceased. It can be obtained in the United States and Canada via importation from Europe, but it is not FDA-approved at this time. We wish to compare the duration of remission of intraarticular triamcinolone hexacetonide (TH) with that of triamcinolone acetonide (TA) in children with juvenile idiopathic arthritis (JIA) and demonstrate its safety in this population. Methods This retrospective chart review included 39 patients with JIA who received intraarticular corticosteroid injections (IACIs) from September 2018 to September 2019. These patients were reviewed and their life-time injections with either TH (41 joints) or TA (124 joints) was noted through May 30, 2021. Patients with concomitant systemic therapy initiation were excluded. The primary outcome was time to relapse. Relapse was defined by the presence of arthritis on physical examination by an attending rheumatologist. Kaplan-Meier curves and a log-rank test were constructed to compare the probability of time to relapse between IACI injections. Additionally, mixed effects cox regression models were constructed to account for multiple injections per participant. Results Kaplan-Meier estimator of median relapse time in months was higher for TH. Based on the log-rank test, TA joints had a higher probability of experiencing a relapse during the study time (p value < 0.001). The hazard of time to relapse was reduced when comparing TH to TA in both unadjusted and adjusted mixed effects cox regression models [unadjusted hazard ratio (95% confidence interval): 0.184 (0.089, 0.381); adjusted hazard ratio (95% confidence interval): 0.189 (0.092, 0.386)]. Conclusions TH has longer duration of action than TA and is associated with less systemic side effects. It should be considered the drug of choice for intraarticular corticosteroid injections in children with JIA.