Table 1

Demographic and baseline characteristics (safety set)

VariableCanakinumab 25 mg n=55Canakinumab 50 mg n=54Canakinumab 100 mg n=54Canakinumab 200 mg n=54Canakinumab 300 mg n=53Canakinumab every 4 weeks n=53Colchicine 0.5 mg n=108
Male, n (%)55 (100.0)51 (94.4)48 (88.9)50 (92.6)51 (96.2)49 (92.5)101 (93.5)
Age, years
 Mean (SD)50.7 (9.72)54.4 (12.18)51.3 (12.41)52.6 (10.78)52.4 (11.30)52.8 (10.38)52.4 (10.69)
 Median (range)52.0 (27–78)53.0 (32–78)51.0 (27–79)53.5 (29–74)51.0 (30–74)53.0 (23–72)54.0 (20–77)
Race, n (%)
 Caucasian42 (76.4)43 (79.6)36 (66.7)39 (72.2)36 (67.9)41 (77.4)87 (80.6)
 Black1 (1.8)1 (1.9)2 (3.7)2 (3.7)3 (5.7)3 (5.7)4 (3.7)
 Asian4 (7.3)4 (7.4)10 (18.5)5 (9.3)4 (7.5)2 (3.8)5 (4.6)
 Other8 (14.5)6 (11.1)6 (11.1)8 (14.8)10 (18.9)7 (13.2)12 (11.1)
BMI, kg/m2
 Mean (SD)31.03 (4.63)30.51 (4.35)29.88 (4.69)30.60 (4.12)30.63 (4.64)29.62 (4.32)30.30 (4.66)
 Median (range)30.0 (22–40)29.9 (22–40)29.8 (21–40)30.4 (20–38)30.4 (17–40)29.7 (18–38)29.2 (22–40)
Classification of gouty arthritis, n (%)*
 Acute monoarticular gouty arthritis15 (27.3)19 (35.2)20 (37.0)11 (20.4)17 (32.1)20 (37.7)37 (34.3)
 Acute oligoarticular gouty arthritis27 (49.1)10 (18.5)22 (40.7)20 (37.0)14 (26.4)13 (24.5)28 (25.9)
 Acute polyarticular gouty arthritis13 (23.6)25 (46.3)12 (22.2)23 (42.6)22 (41.5)20 (37.7)43 (39.8)
Duration of gouty arthritis, n (%)
 <1 year3 (5.5)3 (5.6)2 (3.7)6 (11.1)4 (7.5)2 (3.8)9 (8.3)
 1–5 years13 (23.6)23 (42.6)25 (46.3)14 (25.9)20 (37.7)15 (28.3)39 (36.1)
 6–10 years15 (27.3)6 (11.1)12 (22.2)15 (27.8)10 (18.9)18 (34.0)27 (25.0)
 >10 years24 (43.6)22 (40.7)15 (27.8)19 (35.2)19 (35.8)18 (34.0)33 (30.6)
Number of flares in previous year
 Mean (SD)3.7 (2.27)4.3 (2.82)3.6 (2.26)4.7 (4.51)4.5 (3.68)4.4 (4.13)4.3 (3.82)
 Median (range)3.0 (1–14)3.0 (2–14)3.0 (2–12)3.0 (1–25)4.0 (2–20)3.0 (2–24)3.0 (1–25)
Allopurinol dose at baseline, mg daily
 Mean (SD)261.8 (65.2)263.0 (65.3)263.0 (65.3)257.4 (66.2)264.2 (65.3)258.5 (66.3)261.1 (65.3)
 Median (range)300.0 (100–300)300.0 (100–300)300.0 (100–300)300.0 (100–300)300.0 (100–300)300.0 (100–300)300.0 (100–300)
 Patients starting allopurinol before baseline, n (%)6 (10.9)8 (14.8)10 (18.5)8 (14.8)6 (11.3)8 (15.1)12 (11.1)
Creatinine clearance (ml/min), n (%)
 Low2 (3.6)2 (3.7)2 (3.7)4 (7.4)7 (13.2)2 (3.8)6 (5.6)
 Normal31 (56.4)27 (50.0)27 (50.0)26 (48.1)19 (35.8)27 (50.9)58 (53.7)
 High22 (40.0)25 (46.3)25 (46.3)24 (44.4)27 (50.9)24 (45.3)44 (40.7)
Serum urate, n (%)
 ≥6 mg/dl50 (90.9)48 (88.9)49 (90.7)50 (92.6)49 (92.5)46 (85.2)96 (88.9)
 ≥9 mg/dl30 (54.5)19 (35.2)20 (37.0)28 (51.9)25 (47.2)22 (41.5)51 (47.2)
CRP, mg/l
 Mean (SD)5.9 (9.88)9.1 (18.84)4.5 (8.02)8.7 (15.40)7.8 (15.98)5.9 (6.59)5.9 (8.30)
 Median (range)2.9 (0–70)3.4 (0–93)1.8 (0–51)3.7 (0–93)3.2 (0–81)3.1 (0–30)2.7 (0–49)
SAA, mg/l
 Mean (SD)8.7 (11.90)18.8 (53.89)8.2 (17.35)18.3 (61.46)§15.6 (61.90)12.4 (22.47)11.5 (28.71)
 Median (range)3.8 (1–61)4.9 (0–364)3.7 (0–120)5.5 (1–438)4.3 (1–446)4.8 (0–139)4.6 (0–270)
HAQ SDI score
 Mean (SD)0.38 (0.47)0.48 (0.60)0.39 (0.59)0.38 (0.55)0.35 (0.58)0.42 (0.63)0.42 (0.66)
 Median (range)0.25 (0–2.0)0.25 (0–2.1)0.06 (0–2.6)0 (0–2.5)0 (0–2.1)0.13 (0–2.1)0.06 (0–2.8)
Employment status
 Working in paid, unpaid or voluntary employment40 (72.7)28 (51.9)35 (64.8)37 (68.5)37 (69.8)35 (66.0)73 (67.6)
  • * p=0.016 from χ2 test for comparability across all groups.

  • Creatinine clearance estimated using the Cockcroft–Gault formula. Normal range for women aged: 16–50 years, 65–110 ml/min; 51–70 years, 50–90 ml/min; 71–110 years, 35–60 ml/min. Normal range for men aged: 16–50 years, 80–125 ml/min; 51–70 years, 55–100 ml/min; 71–110 years, 40–75 ml/min.

  • Data missing for one patient.

  • § Data missing for two patients.

  • Data missing for four patients.

    BMI, body mass index; CRP, C reactive protein; HAQ SDI, Health Assessment Questionnaire Standard Disability Index; SAA, serum amyloid A; SD, standard deviation.