Background Patients (pts) with peripheral SpA (pSpA) manifest with peripheral arthritis, enthesitis, and/or dactylitis. ABILITY-2 has demonstrated the efficacy of adalimumab (ADA) vs. placebo (PBO) over 12 weeks (wk). No long-term data exist from a prospective trial on the efficacy and safety of a TNF-inhibitor for specific clinical features of pSpA.

Objectives To evaluate 2-year (yr) clinical/remission response and safety of ADA in pSpA

Methods ABILITY-2 is an ongoing, multicenter phase 3 study. Eligible pts were age ≥18 yrs, fulfilled ASAS peripheral SpA criteria, had active disease and inadequate response or intolerance to NSAIDs. Pts with history of psoriasis/psoriatic arthritis and total back pain VAS ≥20 mm were excluded. Pts were randomized to ADA 40 mg every other wk or PBO for 12 wks followed by a 144-wk open-label extension. The primary endpoint was the pSpA Response Criteria (PSpARC40) previously described.¹ Yr 2 data are described here. Assessments through wk 104 include: tender joint count (TJC78), swollen joint count (SJC76), enthesitis count (29 sites based on MASES, SPARCC and Leeds scores), and hs-CRP. ASDAS and PSpARC40 responses were calculated. Remission was also defined as score =0 during follow-up among pts having baseline (BL) score >0 for joint counts and/or enthesitis scores.

Results 165 pts (ADA 84/PBO 81) were randomized. At BL 163 (99%) had ≥1 TJC (mean 13.4), 154 (93%) had ≥1 SJC (mean 7.2), 143 (87%) had ≥1 enthesitis site (mean total 8.1, Leeds 2.3, SPARCC 5.0, MASES 4.5), but only 37 (23%) had dactylitis. Approximately 2/3 of pts who reached wk 52 or wk 104 achieved PSpARC40 and more than half were in ASDAS inactive disease state (Table). Enthesitis (Leeds, SPARCC, or MASES score =0) or arthritis remission (SJC or TJC=0) were observed in about 60% of pts at wk 104. Among pts with tender and swollen joints and enthesitis at BL, 29% were free of arthritis and enthesitis at wk 104. Based on 272.7 patient-years (PYs) of exposure to ADA, serious AE rate was 8.1 events/PY and serious infection rate 1.1 events/PY. There were 2 deaths: 1 pt died from a brain stem hemorrhage after a car accident and 1 pt died from a pulmonary embolism.

Conclusions In pts with pSpA, sustained response and a high rate of arthritis and/or enthesitis remission were observed with up to 2 yrs of ADA treatment.

References

1. Mease P et al. Ann Rheum Dis 2012;71(Suppl3):250.

Acknowledgements AbbVie funded the study (NCT01064856), contributed to its design and was involved in the collection, analysis, and interpretation of the data, and in the writing, review, and approval of the publication. Statistical support was provided by Ying Zhang, PhD, of AbbVie. Medical writing support was provided by Kathleen V. Kastenholz, PharmD, MS, of AbbVie.

Disclosure of Interest F. Van den Bosch Grant/research support: AbbVie, Celgene, Janssen, Merck, Novartis, Pfizer, and UCB, Consultant for: AbbVie, Celgene, Janssen, Merck, Novartis, Pfizer, and UCB, Speakers bureau: AbbVie, Celgene, Janssen, Merck, Novartis, Pfizer, and UCB, P. Mease Grant/research support: AbbVie, Amgen, Biogen Idec, Bristol Myers, Celgene, Genentech, Janssen, Lilly, Merck, Novartis, Pfizer, UCB, and Vertex, Consultant for: AbbVie, Amgen, Biogen Idec, Bristol Myers, Celgene, Genentech, Janssen, Lilly, Merck, Novartis, Pfizer, UCB, and Vertex, Speakers bureau: AbbVie, Amgen, Biogen Idec, Bristol Myers, Celgene, Genentech, Janssen, Lilly, Merck, Novartis, Pfizer, UCB, and Vertex, J. Sieper Grant/research support: AbbVie, Merck, Pfizer, and UCB, Consultant for: AbbVie, Merck, Pfizer, and UCB, Speakers bureau: AbbVie, Merck, Pfizer, and UCB, D. Baeten Grant/research support: AbbVie, BMS, Boehringer Ingelheim, Centocor, Janssen, MSD, Novartis, Pfizer, and UCB, Consultant for: AbbVie, BMS, Boehringer Ingelheim, Centocor, Janssen, MSD, Novartis, Pfizer, and UCB, Speakers bureau: AbbVie, BMS, Boehringer Ingelheim, Centocor, Janssen, MSD, Novartis, Pfizer, and UCB, P. Karunaratne Shareholder of: AbbVie, Employee of: AbbVie, I.-H. Song Shareholder of: AbbVie, Employee of: AbbVie, A. Pangan Shareholder of: AbbVie, Employee of: AbbVie

DOI 10.1136/annrheumdis-2014-eular.1337