Nelson 2011

Methods	Phase IIb, randomised, dose‐ranging, parallel‐design trial (PROTON)
Participants	121 participants Country: not stated Inclusion criteria: chronic hepatitis C, genotype 1, treatment‐naive participants. Exclusion criteria: cirrhosis.
Interventions	Experimental group: Group 1: 95 participants: PSI‐7977 200 or 400 mg daily for 12 weeks. Control group: Group 2: 26 participants: placebo for 12 weeks. Co‐intervention in both groups: peg‐IFN α‐2a for 24‐48 weeks in a response‐guided regimen. RBV for 24‐48 weeks in a response‐guided regimen.
Outcomes	Not clearly stated.
Notes	We contacted the trial authors about whole risk of bias assessment, male:female ratio, SVR results and AEs.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Insufficient information
Allocation concealment (selection bias)	Unclear risk	Insufficient information
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Use of placebo suggests blinding, but method not described
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not described
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	There was insufficient information to assess whether missing data were likely to induce bias on the results
Selective reporting (reporting bias)	Unclear risk	No protocol available. Not enough information given
Vested‐interest bias	Unclear risk	It was uncertain how the trial was sponsored
Other bias	Low risk	The trial may or may not have been free of other domains that could put it at risk of bias