Improvement of Fatigue in Patients with Ankylosing Spondylitis Receiving Tofacitinib: Analyses of a Phase 3 Randomized Controlled Trial

IntroductionFatigue is a key symptom in patients with ankylosing spondylitis (AS). The objective of this analysis was to estimate the median time to initial and stable improvement events in fatigue in patients with AS receiving tofacitinib.MethodsThis post hoc analysis used data from a phase 3 trial (NCT03502616) in patients with active AS receiving tofacitinib 5 mg twice daily or placebo. Time to improvement in fatigue was assessed using the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) total score, experience domain score, and impact domain score. The rapidity of improvement was assessed by time-to-event analyses (nonparametric Kaplan-Meier models); initial improvement events (i.e., time to first week of FACIT-F improvement) and stable improvement events (i.e., time to first week of FACIT-F improvement, sustained to 16 weeks) were examined.ResultsOverall, 269 patients were assessed (mean disease duration: 14.2 [standard deviation (SD): 9.8] years; mean baseline FACIT-F total score: 27.2 [SD: 9.3]). Median times to initial and stable improvement events in FACIT-F total and domain scores were significantly shorter and occurred in more patients receiving tofacitinib than placebo. Median time to initial and stable improvement events of 6 points in FACIT-F total score were 8 and 12 weeks with tofacitinib, respectively (placebo: not reached); 70.0% versus 48.5% of patients receiving tofacitinib versus placebo, respectively, experienced initial improvements of 6 points in FACIT-F total score within 16 weeks.ConclusionsImprovements in fatigue occurred more rapidly with tofacitinib than with placebo. These results may be useful for healthcare providers when discussing tofacitinib treatment expectations with patients.Trial RegistrationClinicalTrials.gov: NCT03502616 (June 7, 2018).