Table 2

Efficacy end points at weeks 9, 12 and 16

End pointWeek 9Week 12Week 16
TabalumabTabalumabTabalumab
Placebo (N=35)30 mg (N=35)80 mg (N=28)p ValuePlacebo (N=35)30 mg (N=35)80 mg (N=28)p ValuePlacebo (N=35)30 mg (N=35)80 mg (N=28)p Value
ACR20*†
 n/N (%)6/35 (17.1)14/35 (40.0)12/28 (42.9)0.0129/35 (25.7)14/35 (40.0)13/28 (46.4)0.0706/35 (17.1)9/35 (25.7)8/28 (28.6)0.198
ACR50*†
 n/N (%)0/35 (0.0)9/35 (25.7)5/28 (17.9)0.0011/35 (2.9)6/35 (17.1)3/28 (10.7)0.0681/35 (2.9)4/35 (11.4)4/28 (14.3)0.101
ACR70*†
 n/N (%)0/35 (0.0)3/35 (8.6)3/28 (10.7)0.0650/35 (0.0)3/35 (8.6)2/28 (7.1)0.1040/35 (0.0)1/35 (2.9)1/28 (3.6)0.411
DAS28-CRP<3.2*
 n/N (%)1/35 (3.2)6/35 (18.8)7/28 (26.9)0.0141/35 (3.3)5/35 (16.7)4/28 (16.7)0.0660/35 (0.0)5/35 (14.3)6/28 (21.4)0.005‡
DAS28-CRP<2.6*
 n/N (%)1/35 (3.2)3/35 (9.4)5/28 (19.2)0.1100/35 (0.0)3/35 (10.0)3/28 (12.5)0.0640/35 (0.0)3/35 (8.6)2/28 (7.1)0.104‡
DAS28-CRP§
 N313225303023343526
 Mean change−0.50±−1.42±−1.59±−0.76±−1.50±−1.40±−0.61±−0.91±−1.29±
 SD1.061.221.25<0.0010.911.101.16<0.0011.041.140.930.016‡
CRP¶
 N3132260.038303024353527
 Median % change−8.07−32.98−23.69−29.78−15.97−22.550.996−29.15−5.72−20.190.650‡
EULAR response(good+moderate)*
 n/N (%)9/31 (29.0)22/32 (68.8)17/25 (68.0)<0.00115/30 (50.0)21/30 (70.0)15/23 (65.2)0.08515/34 (44.1)13/35 (37.1)17/26 (65.4)0.398‡
Regional subanalysisWeek 9 (Observed)**Week 12 (Observed)**Week 16 (NRI)
ACR20 (US)
 n/N (%)3/12 (25.0)6/16 (37.5)5/14 (35.7)NC6/12 (50.0)4/16 (25.0)3/12 (25.0)NC3/14 (21.4)5/18 (27.8)2/16 (12.5)NC
ACR20 (OUS)
 n/N (%)3/19 (15.8)8/16 (50.0)7/12 (58.3)NC3/19 (15.8)10/15 (66.7)10/12 (83.3)NC3/21 (14.3)4/17 (23.5)6/12 (50.0)NC
ACR50 (US)
 n/N (%)0/12 (0.0)4/16 (25.0)2/14 (14.3)NC1/12 (8.3)2/16 (12.5)1/12 (8.3)NC1/14 (7.1)1/18 (5.6)1/16 (6.3)NC
ACR50 (OUS)
 n/N (%)0/19 (0.0)5/16 (31.3)3/12 (25.0)NC0/19 (0.0)4/15 (26.7)2/12 (16.7)NC0/21 (0.0)3/17 (17.6)3/12 (25.0)NC
  • OUS countries were Argentina (n=12), Austria (n=7), Belgium (n=1), Brazil (n=15), Canada (n=4), Germany (n=4), Poland (n=6) and Puerto Rico (n=1).

  • US patients (n=48).

  • Values are n/N (%) unless otherwise noted. For the NRI, patients who discontinued from the study prior to week 16 were imputed as non-responders.

  • *One-sided Fisher exact test of tabalumab (the two dose groups combined) versus placebo.

  • †Imputed by NRI.

  • ‡Imputed by LOCF (last-observation-carried-forward).

  • §One-sided ANCOVA test of tabalumab (the two dose groups combined) versus placebo with treatment and baseline value in the model.

  • ¶Two-sided ranked ANCOVA with treatment and the standardised rank baseline value in the model based on mean percentage change in tabalumab (the two dose groups combined) versus placebo.

  • **For regional subanalysis, data at weeks 9 and 12 are observed, whereas data at the 16-week primary end point are imputed by NRI.

  • ACR20, proportion of patients achieving a 20% improvement in American College of Rheumatology criteria (ACR); ACR50, proportion of patients achieving a 50% improvement in ACR criteria; ACR70, proportion of patients achieving a 70% improvement in ACR criteria; CRP, C-reactive protein; DAS28, Disease Activity Score based on 28-joint count; EULAR, European League Against Rheumatism index; n, the number of responders; N, the number of patients assessed at that time point; NC, not calculated; NRI, non-responder imputation; OUS, outside of the USA; US, USA.