Abstract
Background: Dactylitis, a hallmark of psoriatic arthritis (PsA), is a uniformly diffuse and sometimes painful swelling of the fingers and/or toes.1 Up to 50% of patients (pts) with PsA may experience dactylitis;1,2 as such, dactylitis is an accepted domain of PsA that should be considered in treatment decisions.3 In PsA, dactylitis typically involves feet more than hands; dactylitic joints more frequently have erosive damage, compared with non-dactylitic joints.2 There remains a need for effective therapies to treat dactylitis in pts with PsA. Improvements in dactylitis have been associated with tofacitinib, an oral Janus kinase inhibitor for the treatment of PsA.4,5 Objectives: To assess the effect of tofacitinib on dactylitis by location (hands/feet) and individual digit involvement in pts with PsA. Methods: These post hoc analyses used data pooled from two Phase 3 studies (12-month OPAL Broaden [NCT01877668];5 6-month OPAL Beyond [NCT01882439]4) in pts with active PsA treated with tofacitinib 5 mg twice daily (BID; approved dose; to Month [M] 6), tofacitinib 10 mg BID (to M6) or placebo (PBO; to M3); pts were treated continuously with a single conventional synthetic disease-modifying antirheumatic drug. Pts were categorised by the presence of dactylitis at baseline (BL) in the hands and/or feet. Endpoints included change from BL in Dactylitis Severity Score (DSS),6 the number of dactylitic digits and the proportion of pts with dactylitis in individual digits at M1, M3 and M6. Descriptive statistics were generated by visit and treatment arm. Results: Data were pooled from 373 pts with DSS >0 at BL. BL characteristics, including gender, age, race, body mass index, PsA duration, BL DSS and dactylitic digits count were similar across dactylitis groups and treatment groups, except for pts with dactylitis in both the hands and feet, who had higher DSS compared to those with dactylitis in the hands or feet only, likely due to having more dactylitic digits (data not shown). Regardless of location, pts treated with tofacitinib had cumulative improvements from BL to M6 in DSS (Figure 1a) and in the number of dactylitic digits (Figure 1b); improvements in DSS were greater at M1 and M3, compared with PBO. Pts treated with tofacitinib 10 mg BID typically had numerically greater improvements in DSS, compared with pts treated with tofacitinib 5 mg BID (Figure 1a). Most pts treated with tofacitinib experienced improvement of dactylitis across all fingers and toes (Figure 1c–f); mean dactylitis presence was ≤15% at M6 in pts treated with tofacitinib for all digits. Generally, at M1 and M3, fewer pts treated with tofacitinib had dactylitis in any digit, compared with PBO (Figure 1c–f). Conclusion: Among pts with pre-existing dactylitis, treatment with tofacitinib resulted in improvements in dactylitis in hands, feet, or both, and in all digits as early as M1, and up to M6. References: [1]Kaeley et al. Semin Arthritis Rheum 2018; 48: 263-273. [2]Brockbank et al. Ann Rheum Dis 2005; 64: 188-190. [3]Coates et al. Arthritis Rheumatol 2016; 68: 1060-1071. [4]Gladman et al. N Engl J Med 2017; 377: 1525-1536. [5]Mease et al. N Engl J Med 2017; 377: 1537-1550. [6]Helliwell et al. J Rheumatol 2005; 32: 1745-1750. Acknowledgements: Study sponsored by Pfizer Inc. Medical writing support was provided by Eric Comeau, CMC Connect, and funded by Pfizer Inc. Disclosure of Interests: Ana-Maria Orbai Consultant of: Eli Lilly, Novartis, Pfizer Inc, Grant/research support from: AbbVie, Eli Lilly, Horizon, Janssen, Novartis, Philip J Mease Speakers bureau: AbbVie, Amgen, Bristol-Myers Squibb, Celgene, Eli Lilly, Genentech, Janssen, Novartis, Pfizer Inc, UCB, Consultant of: AbbVie, Amgen, Boehringer Ingelheim, Bristol-Myers Squibb, Celgene, Eli Lilly, Galapagos, Gilead, Janssen, Novartis, Pfizer Inc, Sun, UCB, Grant/research support from: AbbVie, Amgen, Boehringer Ingelheim, Bristol-Myers Squibb, Celgene, Eli Lilly, Galapagos, Gilead, Janssen, Novartis, Pfizer Inc, Sun, UCB, Philip Helliwell Paid instructor for: Janssen, Novartis, Pfizer Inc, Consultant of: Eli Lilly, Oliver FitzGerald Speakers bureau: AbbVie, Janssen, Pfizer Inc, Consultant of: Bristol-Myers Squibb, Celgene, Eli Lilly, Janssen, Pfizer Inc, Grant/research support from: AbbVie, Bristol-Myers Squibb, Eli Lilly, Novartis and Pfizer Inc, Mohammed Bdewi Speakers bureau: AbbVie, Pfizer Inc, Dona Fleishaker Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Rajiv Mundayat Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Pamela Young Shareholder of: Pfizer Inc, Employee of: Pfizer Inc.