Talk: Abatacept in Psoriatic Arthritis: Results of a Phase II Study (2009 ACR/ARHP Annual Scientific Meeting)

Monday, October 19, 2009: 5:30 PM

108 B (Pennsylvania Convention Center)

P. Mease¹, M. Genovese², C. Ritchlin³, J. Wollenhaupt⁴, Paul P. Tak⁵, A. Kivitz⁶, G. Gladstein⁷, O. Bahary⁸, S. Kelly⁸, J. Teng⁸, J.-C. Becker⁸ and D. Gladman⁹, ¹Swedish Medical Ctr/Univ. of Washington, Seattle, WA, ²Stanford Univ., Palo Alto, CA, ³Univ. of Rochester, Rochester, NY, ⁴Klinikum Eilbek, Hamburg, Germany, ⁵Academic Medical Center/ University of Amsterdam, Amsterdam, Netherlands, ⁶Altoona Center for Clinical Research, Duncansville, PA, ⁷New England Research Assoc, Trumbull, CT, ⁸Bristol-Myers Squibb, Princeton, NJ, ⁹Univ. of Toronto, Toronto, ON

Presentation Number: 1260

Purpose: Abatacept (ABA) is a selective co-stimulation modulator approved for the treatment of RA and juvenile idiopathic arthritis. Here we assess the efficacy of ABA in patients (pts) with psoriatic arthritis (PsA) previously exposed to DMARDs in a phase II study.

Method: In this double-blind study, PsA pts with a target lesion (TL) ≥ 2 cm were randomized (1:1:1:1) to placebo (PBO) and ABA at 3, 10, and 30/10 (30 x 2 followed by 10) mg/kg (mpk). Treatments were administered on Days 1, 15, 29, and then once every 28 days. The primary endpoint was ACR20 at Day 169. Secondary endpoints were Health Assessment Questionnaire (HAQ), Short Form-36 (SF-36), investigator global assessment (IGA), TL score at Day 169, and safety. Psoriasis area and severity index (PASI) and magnetic resonance imaging (MRI) score of the joints at Day 169 were exploratory.

Results: Baseline characteristics were similar among groups except for more pts being previously exposed to anti-TNF therapies in the 30/10 mpk arm (51%) than other arms (29-36%). Of 170 pts treated, 147 completed first 6 months of treatment; 23 pts discontinued (7 for AEs and 10 for lack of efficacy). Significant number of pts achieved ACR20 with ABA (10 and 30/10 mpk) compared to PBO (table). Improvements in HAQ, physical component summary (PCS) and MRI score were also seen with ABA compared to PBO. The skin response in terms of TL and PASI showed a separation between PBO and ABA arms, with the 3 mpk dose showing the most separation; an improved IGA response was seen only with 3 mpk. Improvements in ACR20 and TL were greater in anti-TNF-naive pts than in pts pre-exposed to anti-TNF therapies. The safety profiles were similar among arms.

Response	ABA			PBO n = 42
Response	30/10 mpk* n = 43	10 mpk n = 40	3 mpk N = 45	PBO n = 42
*Joint*
ACR20† p vs. PBO	42 (27, 57) 0.022	48 (32, 63) 0.006	33 (20, 47) 0.121	19 (7, 31) NA
Pre-exposed to anti-TNF therapy
No, n ACR20† Yes, n ACR20†	21 48 (26, 69) 22 36 (16, 57)	27 56 (37, 74) 13 31 (6, 56)	29 35 (17, 52) 16 31 (9, 54)	30 20 (6, 34) 12 17 (-4, 38)
MRI of joints‡
Erosion Synovitis Edema	0.3 (3.5) -0.8 (3.1) -0.5 (1.9)	-0.6 (4.2) -1.4 (3.0) -1.1 (2.6)	0.5 (2.4) -0.2 (2.9) -0.3 (1.7)	1.5 (7.4) 0.8 (4.3) 0.4 (3.3)
*Skin*
TL50†	30 (17, 44)	33 (18, 47)	36 (22, 50)	17 (5, 28)
TL75†	16 (5, 27)	10 (1, 19)	29 (16, 42)	10 (1, 18)
*Patient-reported outcomes*
HAQ§†	35 (21, 49)	45 (30, 60)	36 (22, 50)	19 (7, 31)
PCS‡	7.3 (1.9)	9.3 (1.9)	6.3 (1.8)	0.2 (1.9)
*30 mpk followed by 10 mpk; †% pts with 95% CI; ‡Adjusted mean (± SE) change from baseline; §Improvement of ≥ 0.3 unit from baseline

Conclusion: ABA at 10 mpk significantly improved ACR20 and physical function in PsA pts, consistent with previous trials in RA. ABA treatment also resulted in less joint damage by MRI evaluation. All doses showed improvement in TL score with the 3 mpk dose showing the most.

Keywords: abatacept and psoriatic arthritis

Disclosure: P. Mease, Bristol-Myers Squibb, 2, Bristol-Myers Squibb, 5, Bristol-Myers Squibb, 8 ; M. Genovese, BMS, 2, BMS, 5, BMS, 8 ; C. Ritchlin, Centocor, Inc., 2, Amgen, Roche, Sanofi, Centocor, 5, Wyeth Pharmaceuticals, 5, Bristol-Myers Squibb, 5 ; J. Wollenhaupt, None; P. P. Tak, BMS, 2 ; A. Kivitz, takeda, novartis, roche, 8, Amgen, 8 ; G. Gladstein, Pfizer Inc, Genentech, BMS, Roche, Forest, Cephalon, Regeneron, Centocor, 2, Bristol-Myers Squibb, 8 ; O. Bahary, Bristol-Myers Squibb, 3, Bristol-Myers Squibb, 1 ; S. Kelly, Bristol-Myers Squibb, 3, Bristol-Myers Squibb, 1 ; J. Teng, Bristol-Myers Squibb, 3, Bristol-Myers Squibb, 1 ; J. -. C. Becker, Bristol-Myers Squibb, 3, Bristol-Myers Squibb, 1 ; D. Gladman, Abbott, Amgen, Centocor, Schering, Wyeth, Roche, UCB, 5 .

1260 - Abatacept in Psoriatic Arthritis: Results of a Phase II Study