Identification of distinct disease activity trajectories in patients with psoriatic arthritis receiving tofacitinib: a post hoc analysis of two phase 3 studies

OBJECTIVE: To capture variations in tofacitinib treatment response in psoriatic arthritis (PsA) by identifying patient groups with distinct disease activity trajectories.

METHODS: Data were pooled post hoc from two phase 3 studies (OPAL Broaden, OPAL Beyond) in patients with PsA receiving tofacitinib 5 or 10 mg twice daily (n=225, n=226, respectively). Psoriatic Arthritis Disease Activity Score (PASDAS) to month 6 was used in group-based trajectory modelling to identify distinct treatment response groups based on disease state (very low/low/moderate/high disease activity (VLDA/LDA/MoDA/HDA, respectively)). Baseline characteristics, PASDAS components to month 6 and adverse events (AEs) were assessed.

RESULTS: Five trajectory groups were identified for both tofacitinib doses: groups improved from MoDA→VLDA/LDA (group 1); HDA→VLDA (group 2); HDA→MoDA rapidly (group 3) or gradually (group 4) or remained in HDA (group 5). Groups 4/5 generally had significantly higher baseline PsA clinical domain scores than groups 1‒3, except for Psoriasis Area and Severity Index/Nail Psoriasis Severity Index. Baseline Leeds Enthesitis Index/Spondyloarthritis Research Consortium of Canada enthesitis scores and tender joint counts were significantly higher in group 4 vs group 2. PASDAS components generally improved to month 6 in all groups, consistent with modelled trajectories. There were no clear trends in AEs across groups.

CONCLUSIONS: In patients with PsA receiving tofacitinib, five distinct trajectory groups were identified with different baseline characteristics and treatment outcomes, but no clear trends in AEs. The tofacitinib 5 and 10 mg twice daily models showed comparable trajectories and baseline characteristics. In patients with HDA, enthesitis and tender joint count may impact timing and/or magnitude of response to tofacitinib. Identifying characteristics that impact treatment response may aid personalised treatment algorithm development.

TRIAL REGISTRATION NUMBERS: NCT01877668/NCT01882439.