STYLE 2020.

Study characteristics
Methods	RCT, placebo‐controlled, double‐blind trial Date of study: May 2017 ‐ January 2019 Location: 13 sites in Canada and 28 sites the USA Phase 3
Participants	Randomised: 303 participants Inclusion criteria Patients aged ≥ 18 years with moderate‐to‐severe plaque psoriasis of the scalp, defined as Scalp Physician Global Assessment (ScPGA) score ≥ 3, psoriasis‐involved scalp surface area (SSA) ≥ 20% Inadequate response or intolerance to ≥ 1 topical therapy for plaque psoriasis of the scalp Moderate‐to‐severe plaque psoriasis, defined as PASI score ≥ 12, BSA ≥ 10%, and sPGA ≥ 3 Exclusion criteria Current or planned concurrent use of topical therapies (including medicated shampoos, coal tar, and salicylic acid preparations) within 2 weeks, or conventional systemic therapy for psoriasis within 4 weeks Intralesional corticosteroids on the scalp within 2 weeks Phototherapy treatment of body or scalp lesions within 4 weeks Use of biologics within 12 to 24 weeks Prolonged sun or ultraviolet light exposure Baseline characteristics N = 303, mean age of 46.9 years and 62% men Dropouts and withdrawals 51/303 (17%): Apremilast group (33), Placebo group (18) AEs: Apremilast group (8), Placebo group (3) Lack of efficacy: Apremilast group (4), Palcebo group (3) Withdrawal by subject: Apremilast group (16), Palcebo group (6) Lost to follow‐up: Apremilast group (3), Placebo group (1) Non‐compliance with study drug: Apremilast group (0), Placebo group (3) Protocol deviation: Apremilast group (1), Placebo group (2) Miscellaneous: Apremilast group (1), Placebo group (0)
Interventions	Intervention A. Apremilast 30 mg tablets orally twice a day for 16 weeks Control intervention B. Placebo tablets twice a day for 16 weeks
Outcomes	At week 16 Primary composite outcome Percentage of participants with Scalp Physician Global Assessment (ScPGA) Score of Clear (0) or Almost Clear (1) Secondary outcomes Percentage of Participants With ≥ 4‐Point Reduction (Improvement) From Baseline in the Whole Body Itch Numeric Rating Score (NRS) and Scalp Itch NRS scores Change From baseline in DLQI Total Score Number of participants with treatment emergent adverse events (TEAE) Proportion of participants with sPGA of 0 (clear) or 1 (almost clear) with a ≥ 2‐point reduction from baseline Percentage change from baseline in BSA Percentage change from baseline in PASI score.
Notes	Funding source Quote (p 2): "The authors acknowledge financial support for this study from Celgene Corporation. The authors received editorial support in the preparation of this report from Amy Shaberman, PhD, of Peloton Advantage, LLC, an OPEN Health company, Parsippany, NJ, USA, sponsored by Celgene Corporation, Summit, NJ, USA. The authors, however, directed and are fully responsible for all content and editorial decisions for this report." Conflict of interests Quote (p 3‐4):"ASVV: AbbVie, Allergan, Celgene Corporation, Derm Tech, Dermira, Novartis, and Valeant – honoraria for advisory board and/or consulting; Merck – pension (ex‐spouse). LSG: Celgene Corporation, LEO Pharma, Novartis, Pfizer, and Stiefel/GlaxoSmithKline – investigator and/or consultant. ML: Mount Sinai (which receives funds from Boehringer Ingelheim, Celgene Corporation, Eli Lilly, Janssen/Johnson & Johnson, Kadmon, MedImmune/AstraZeneca, Novartis, Pfizer, and ViDac). BS: AbbVie, Almirall, Amgen, Arena, Boehringer Ingelheim, Bristol‐Myers Squibb, Celgene Corporation, Dermavant, Dermira, Eli Lilly, GlaxoSmithKline, Janssen, Kyowa Hakko Kirin, LEO Pharma, Medac, Meiji Seika Pharma, Menlo Therapeutics, Novartis, Ortho Dermatologics/Valeant, Pfizer, Regeneron, Sanofi‐Genzyme, Sebela Pharmaceuticals, Sun Pharma, and UCB Pharma – honoraria as a consultant and advisory board member; AbbVie, Boehringer Ingelheim, Celgene Corporation, Eli Lilly, Galderma, GlaxoSmithKline, Janssen, Merck, Pfizer, and Sienna – payments (to the University of Connecticut) as an investigator; Corrona Psoriasis Registry – fees as a scientific director; AbbVie and Janssen – grant support (to the University of Connecticut for Fellowship Program). CL: AbbVie, Boehringer Ingelheim, Celgene Corporation, Eli Lilly, Janssen, Merck, Novartis, Pfizer, Sun Pharma, and Valeant – principal investigator/consultant. ST: No conflicts or potential conflicts of interest to disclose. AC: AbbVie, Amgen, AstraZeneca, Boehringer Ingelheim, Celgene Corporation, Dermira, Eli Lilly, Janssen, Maruho, Novartis, Pfizer, Stiefel/ GlaxoSmithKline, Sun Pharma, and UCB – investigator; Celgene Corporation – consultant. HS: Celgene Corporation, Janssen, Lilly, and Novartis – grants received as an investigator. ZZ, MP, & YW: Celgene Corporation – employment."
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote (p 9): "For the placebo‐controlled phase, study personnel randomized patients (2:1), using a permuted block randomization and centralized interactive response technology, to receive apremilast 30 mg BID or placebo for 16 weeks." Comment: probably done
Allocation concealment (selection bias)	Low risk	Quote (p 9): "For the placebo‐controlled phase, study personnel randomized patients (2:1), using a permuted block randomization and centralized interactive response technology, to receive apremilast 30 mg BID or placebo for 16 weeks." Comment: probably done
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote (p 9): "The study sponsor, site, contract research organization (CRO) personnel, and patients were blinded to treatment allocation through Week 16" Comment: probably done
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote (p 9): "The study sponsor, site, contract research organization (CRO) personnel, and patients were blinded to treatment allocation through Week 16 Comment: probably done
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Randomly assigned 303, analysed 303 Management of missing data:Quote (p 9, 10):"missing values at Week 16 were imputed using the MI method... Primary and secondary endpoints were analyzed in the intent‐to‐treat (ITT) population, defined as all randomized patients." Results for PASI and PGA were reported in supplmentary appendix Comment: number of analysed pateints not reported for PGA and PASI
Selective reporting (reporting bias)	Low risk	Comment: the protocol for the study was available on ClinicalTrials.gov (NCT03123471). The prespecified outcomes and those mentioned in the Methods section appeared to have been reported. Results are posted on ClinicalTrials.gov.