Efficacy of a step-down regimen of oral prednisolone in axial spondyloarthritis: result of a double-blind randomized controlled trial (COBRA-AS Study).

OBJECTIVES

To evaluate the efficacy and safety of a step-down regimen of oral prednisolone over 24 weeks in patients of axial SpA (axSpA).

METHODS

This proof-of-concept double-blind randomized controlled trial enrolled patients with active axSpA (BASDAI ≥4) having predominantly axial disease (≤1 active joint currently) and inadequate response to NSAIDs. They were randomized to receive either oral prednisolone (n = 32) or placebo (n = 33) at a dose of 60, 40, 30, 20, 15 and 10 mg daily for 1 week each, following which they received 5 mg prednisolone (or placebo) daily for 18 weeks. The primary endpoint was a 50% improvement in the BASDAI (BASDAI50) at week 24. Analysis was intention to treat.

RESULTS

A BASDAI50 was achieved by 12 of 32 patients (37.5%) in the prednisolone arm and 3 of 33 patients (9.1%) in the placebo arm at 24 weeks [difference 28.4% (95% CI 7.9, 46.7)]. However, there was no difference in achieving a 20 or 40% improvement in the Assessment of SpondyloArthritis international Society response between the groups. Although there was a significant intergroup difference in adjusted ΔBASDAI and ΔAnkylosing Spondylitis Disease Activity Score with CRP at 24 weeks, there was no difference at 12 weeks. There was also no significant difference in ΔBASFI, ΔBAS-G or ΔBASMI at 12 or 24 weeks. No serious adverse events were noted. There was significant weight gain in the first 12 weeks in the prednisolone group vs placebo [0.9 (s.d. 0.4) kg], but not at 24 weeks.

CONCLUSIONS

In this small study, oral prednisolone was efficacious in axSpA in achieving the primary outcome, but many crucial secondary outcomes such as functional improvement were not met. Its impact on bone loss was not studied.Trial registration: CTRI/2018/01/011342.