Adalimumab for long-term treatment of psoriatic arthritis: 2-year data from the Adalimumab Effectiveness in Psoriatic Arthritis Trial (ADEPT)

Abstract

Objective: To evaluate the long-term effectiveness and tolerability of adalimumab in the treatment of psoriatic arthritis (PsA).

Methods: Patients with PsA who completed a 24-week, double-blind study of adalimumab versus placebo were eligible to enroll in an open-label extension study and receive adalimumab 40 mg subcutaneously every other week for up to an additional 120 weeks. At the time of this analysis, available efficacy evaluations throughout 2 years of treatment (n = 245) included American College of Rheumatology (ACR) 20%, 50% and 70% improvement scores, measures of joint disease and skin disease, disability and quality of life; modified total Sharp scores (mTSS) were available for 2.75 years of treatment for patients who received adalimumab in the 24-week study.

Results: After 24 weeks of double-blind treatment, the mean change in mTSS was -0.2 for the adalimumab group (N = 144) and 1.0 for the placebo group (N = 152; p<0.001), and outcomes for all individual ACR component variables were significantly improved in adalimumab compared with placebo-treated patients. Compared with 24-week responses, inhibition of radiographic progression and improvements in joint disease were maintained in most patients during long-term, open-label adalimumab treatment. Also, improvements in skin disease were maintained, with >20% of patients achieving the strict criterion of psoriasis area and severity index 100. The nature and frequency of adverse events during long-term adalimumab treatment were consistent with the safety profile during short-term treatment.

Conclusions: The clinical and radiographic efficacy of adalimumab demonstrated during short-term treatment was sustained during long-term treatment. Adalimumab has a favourable risk-benefit profile in patients with PsA.

Trial registration number: NCT00195689.

Figure 1

Percentages of patients achieving American College of Rheumatology (ACR) 20%, 50% and 70% improvement score response status to week 104 based on the duration of exposure to adalimumab (including those patients originally randomly assigned to placebo). Data are last observation carried forward. For patients who had an adalimumab dosage increase, the last observation before the dosage increase was carried forward. N  =  281 at all time points to week 104. Patients originally randomly assigned to receive placebo had a rapid response when switched to adalimumab at week 24.

Figure 2

Percentages of patients achieving psoriasis area and severity index (PASI) 50, PASI 75, PASI 90 and PASI 100 response status to week 104 based on the duration of exposure to adalimumab (including those patients originally randomly assigned to placebo). PASI was assessed only for patients with at least 3% body surface area involvement at enrollment. Data are last observation carried forward. For patients who had an adalimumab dosage increase, the last observation before the dosage increase was carried forward. N  =  128 at all time points to week 104.