NCT00126594.

Study characteristics
Methods	Study name: ‐ Study design: randomised, parallel assignment, phase II (three‐arm trial) Blinding: none, open‐label Study dates: June, 2005 ‐ August, 2013 Date of data cut‐off: not reported Location: 1 country (USA), type of centre: cancer centre (1 study location) Cross‐over study or cross over permitted: not per design; not reported whether cross over was permitted at some point (e.g. upon progression)
Participants	Inclusion criteria: participants with histologically or cytologically confirmed metastatic clear cell RCC 18 years and older participants must have measurable disease, defined as a lesion that can be accurately measured in at least one dimension (longest diameter to be recorded) and measures >= 20 mm with conventional techniques or >= 10 mm with spiral CT scan ECOG performance status =< 1 Exclusion criteria: no prior malignancy is allowed, except for non‐melanoma skin cancer, in situ carcinoma of any site, or other cancers for which the patient has been adequately treated and disease free for 5 years participants must not have received any systemic anticancer therapy for renal cell carcinoma; participants must not have received any radiotherapy for renal cell carcinoma within 4 weeks prior to entering the study or those who have not recovered from adverse events due to agents administered more than 4 weeks earlier participants must not be scheduled to receive another experimental drug while on this study; participants are permitted to be on concomitant bisphosphonates participants must not have a primary brain tumour, any brain metastases, leptomeningeal disease, seizure disorders not controlled with standard medical therapy, or history of stroke More inclusion and exclusion criteria on CT.gov. Sample size: N = 80 Age (median in years (range)): experimental arm: 60.7 (43‐81), control arm: 62.4 (45‐83) Sex (m/f): experimental arm: 29/11, control arm: 32/8 Prognostic factors: ECOG PS, n 0 experimental arm: 25, control arm: 25 1 experimental arm: 15, control arm: 15 MSKCC score, n Low experimental arm: 20, control arm: 21 Intermediate experimental arm: 18, control arm: 19 Poor experimental arm: 2, control arm: 0 Previous nephrectomy, n Yes experimental arm: 39, control arm: 40
Interventions	Experimental arm: sorafenib (400 mg, oral, twice/day) Control arm: sorafenib (400 mg, oral, twice/day) and recombinant interferon alfa‐2b (0.5 MIU, subcutaneous injection, twice/day)
Outcomes	Primary outcome(s) ‐ Secondary outcome(s) Selected grade 3‐4 AEs Time frame: up to 12 months of treatment PFS Time frame: from date of randomisation until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 36 months Median OS Time frame: from the start of protocol therapy to death or date of last follow‐up, up to 36 months Relevant to this review but not reported: QoL, TFST, number of participants who discontinued treatment due to an AE Other outcomes (not relevant to this review): ORR, DoR
Notes	Funding sources: National Cancer Institute (NCI), M.D. Anderson Cancer Center Declarations of Interests: not found Clinical study report available: no Study protocol available: no Statistical analysis plan available: no