SAN DIEGO, CA—Patients with acute gouty arthritis who received canakinumab administered via a prefilled syringe experienced significantly greater pain relief and reduced risk of new attacks compared with triamcinolone acetonide, a study reported at the 2013 ACR/ARHP Annual Meeting.

In this study, canakinumab prefilled syringe had a safety profile similar to that of canakinumab lyophilized powder; these data were also consistent with previous studies of the lyophilized formation, stated Prashanth Sunkureddi, MD, clinical assistant professor of medicine in the Division of Rheumatology at The University of Texas Medical Branch, Galveston, TX, and colleagues.

Canakinumab is a selective, fully human, monoclonal anti-IL-1β antibody that has demonstrated long-term benefits in patients with gouty arthritis by targeting the inflammatory pathway through IL-1β inhibition, the investigators noted.

The 12-week, multicenter, double-blind, triple dummy, active-controlled study included 397 patients who met the ACR 1977 preliminary criteria for acute gouty arthritis (≥3 attacks in the previous year). In addition, patients had to have a contraindication or be intolerant or refractory to NSAIDs and/or colchicine.

The primary objective was to confirm superiority of canakinumab prefilled syringe vs. triamcinolone acetonide in reducing pain intensity in the most affected joint, measured on the 0—100mm VAS scale, at 72 hours postdose. Secondary objectives included evaluation of canakinumab-prefilled syringe vs. triamcinolone acetonide and canakinumab lyophilized powder (which is reconstituted with water) vs. prefilled syringe for time to first new attack, percentage of patients with >1 new attack; and safety over 12 weeks.

Patients were randomized 1:1:1 to receive a single dose of canakinumab prefilled syringe 150mg subcutaneously (n=133), canakinumab lyophilized powder 150mg subcutaneously (n=132) or triamcinolone acetonide 40mg intramuscularly (n=132). Patients were re-dosed “on demand” with each new attack, Dr. Sunkureddi noted. A total of 87.9% of patients completed the study.

Results showed the canakinumab prefilled syringe formulation provided a statistically significant reduction in pain intensity at 72 hours postdose compared with triamcinolone acetonide (estimated difference, -14.9mm; 95% CI -20.6–-9.2, P<0.0001). Least square mean pain scores were comparable for both canakinumab formulations (prefilled syringe, 17.1mm; lyophilized powder, 19.7mm), and both were lower than that for triamcinolone acetonide (32.0mm).

The percentage of patients with at least 1 new attack was also lower with the canakinumab prefilled syringe formulation (9.2%) vs. triamcinolone acetonide (40.3%) (OR 0.15 [95% CI 0.07–0.30]; P<0.0001) and was comparable for both canakinumab formulations (canakinumab lyophilized powder, 9.3%) over the 12-week period.

Administration of canakinumab using a prefilled syringe significantly delayed time to first new attack compared with triamcinolone acetonide (P<0.0001); both canakinumab formulations had similar results for this outcome.

Adverse events (AEs) were observed in 43.6% of patients in both the canakinumab prefilled syringe and triamcinolone acetonide groups and in 42.9% of patients in the canakinumab lyophilized powder group. The efficacy and safety of the two canakinumab formulations were comparable, they concluded.