Krueger 2007.

Study characteristics
Methods	RCT, placebo‐controlled, double‐blind trial Date of study: June 2003 to March 2005 Location: 46 centres in Utah, USA Phase 2
Participants	Randomised: 320 participants Inclusion criteria Participants with moderate‐severe psoriasis Authors' assessment > 6 months, PASI ≥ 12, BSA > 10% Age ≥ 18 Exclusion criteria Had received biologics (ustekinumab 12/23) Had an active infection Had past history of malignant tumours Baseline characteristics N = 320, mean age 45 years, 222 male Dropouts and withdrawals 32/320 (8.8%) Ustekinumab 12/23 45 mg (7) (received no treatment (1) unsatisfactory therapeutic effect (2) AE (5)) Ustekinumab 12/23 90 mg (4) (received no treatment (1), other (3)) Ustekinumab 12/23 45 mg 4‐weekly (3) (AE (2), withdrew consent (1)) Ustekinumab 12/23 90 mg 4‐weekly (4) (unsatisfactory therapeutic effect (1), AE (1), withdrew consent (1), other (1)) Placebo (13) (unsatisfactory therapeutic effect (6), lost to follow‐up (1), withdrew consent (2), other (4))
Interventions	Intervention A. Ustekinumab 12/23 (n = 64), SC, 45 mg, 45 mg 1 dose, 1 week Control intervention B. Ustekinumab 12/23 (n = 64), SC, 90 mg, 45 mg 1 dose, 1 week C. Ustekinumab 12/23 (n = 64), SC, 45 mg, 45 mg/week, 4 weeks D. Ustekinumab 12/23 (n = 64), SC, 90 mg, 45 mg/week, 4 weeks E. Placebo (n = 64), SC
Outcomes	Assessments at 12 weeks Primary outcome Proportion of participants achieving ≥ PASI 75 Secondary outcomes Safety PGA DLQI
Notes	Funding source (p 590): "Supported by Centocore, Malvern, PA" Declaration of interest (p 590‐1): "Dr. Krueger reports receiving fees as a consultant or advisory board member for Abbott, Almirall, Alza, Amgen, Astellas, Boehringer Ingelheim, Barrier Therapeutics, Bristol‐Myers Squibb, Centocor, Connetics, and Genentech; Dr. Langley, for Centocor, Abbott, and Amgen/Wyeth; Dr. Leonardi, for Abbott, Amgen, Centocor, and Genentech; and Dr. Lebwohl, for Abbott, Amgen, Astellas, Centocor, Connetics, Galderma, Genentech, Novartis, PharmaDerm, and Warner Chilcott. Dr. Krueger reports receiving lecture fees from Abbott, Amgen, Boehringer Ingelheim, Centocor, and Connetics; Dr. Langley, from Abbott and Amgen/ Wyeth; Dr. Leonardi, from Abbott, Amgen, Centocor, and Genentech; and Dr. Lebwohl, from Abbott, Astellas, Amgen, Centocor, Connetics, Galderma, Genentech, PharmaDerm, and Warner Chilcott. Dr. Krueger reports receiving stipends for a clinical research fellowship from Amgen and Centocor; Dr. Langley, grant support from Centocor, Abbott, and Amgen/Wyeth; Dr. Leonardi, educational grants from Amgen and Genentech; and Dr. Lebwohl, grants from Abbott, Amgen, Astellas, Centocor, Connetics, Galderma, Genentech, PharmaDerm, and Warner Chilcott. Drs. Yeilding, Guzzo, Wang, and Dooley report being employees of Centocor. Dr. Krueger reports owning stock options from ZARS Pharma; Drs. Yeilding, Guzzo, and Dooley report holding stock and stock options in Johnson & Johnson; and Dr. Wang reports being a stockholder in Johnson & Johnson. No other potential conflict of interest relevant to this article was reported."
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote (p 581): “Patients ... were randomly assigned”. Comment: no description of the method used to guarantee random sequence generation
Allocation concealment (selection bias)	Unclear risk	Quote (p 581): “Patients ... were randomly assigned”. Comment: no description of the method used to guarantee allocation concealment
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote (p 581): “This placebo‐controlled, double‐blind...phase 2 study” Comment: placebo‐controlled
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote (p 581): “This placebo‐controlled, double‐blind...phase 2 study” Comment: no specific description of the method used to guarantee blinding of outcome assessment, but considering that this was a placebo‐controlled trial with no known systematic AEs we considered the risk as low.
Incomplete outcome data (attrition bias) All outcomes	Low risk	320 included, 320 analysed Quote (p 582): "Efficacy data from all patients who underwent randomisation were analysed... Missing values at week 12 were replaced with the most recently available values for all efficacy variables, missing data at other time points were not imputed". Comment: done
Selective reporting (reporting bias)	Low risk	Comment: the protocol for the study was available on ClinicalTrials.gov (NCT00320216). The prespecified outcomes and those mentioned in the Methods section appeared to have been reported.