title: Q-TWiST analysis comparing ipilimumab/dacarbazine vs placebo/dacarbazine for patients with stage III/IV melanoma.
abstract: BACKGROUND
  Study CA184024 was a multinational, randomised, double-blind, phase 3 study comparing ipilimumab/dacarbazine (DTIC) vs placebo/DTIC in patients with untreated stage III/IV melanoma, which showed that ipilimumab significantly improves survival in patients with metastatic melanoma. The objective of this analysis was to compare the quality-adjusted survival experience among patients in this trial.
  
  
  METHODS
  Survival time was partitioned into health states: toxicity, time before progression without toxicity, and relapse until death or end of follow-up. Q-TWiST (quality-adjusted time without symptoms of disease or toxicity of treatment) was calculated as the utility-weighted sum of the mean health state durations. Analyses were repeated over extended follow-up periods.
  
  
  RESULTS
  Based on a combination of trial-based and external utility scores, the Q-TWiST difference in this trial was 0.50 months (P=0.0326) favoring ipilimumab after 1 year. The Q-TWiST difference was 1.5 months with 2 years of follow-up (P=0.0091), 2.36 months at 3 years (P=0.005) and 3.28 months at 4 years (P=0.0074).
  
  
  CONCLUSIONS
  During the first year of study, there was little difference between groups in quality-adjusted survival. However, after 2, 3 and 4 years follow-up for patients with extended survival, the benefits of IPI+DTIC vs PLA+DTIC for advanced melanoma continue to accrue.
authors.affiliation: RTI-Health Solutions, 3040 Cornwallis Road, Post Office Box 12194, Research Triangle Park, NC 27709-2194, USA. bsherrill@rti.org
authors.forename: B
authors.initials: B
authors.lastname: Sherrill
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.forename: S
authors.initials: S
authors.lastname: Kotapati
authors.forename: K
authors.initials: K
authors.lastname: Chin
mesh_terms: D000911:Antibodies, Monoclonal / Q000009:adverse effects* / Q000627:therapeutic use*; D018906:Antineoplastic Agents, Alkylating / Q000009:adverse effects / Q000627:therapeutic use; D003606:Dacarbazine / Q000009:adverse effects / Q000627:therapeutic use*; D018450:Disease Progression; D018572:Disease-Free Survival; D004311:Double-Blind Method; D006801:Humans; D000074324:Ipilimumab; D008545:Melanoma / Q000188:drug therapy* / Q000401:mortality* / Q000473:pathology; D009367:Neoplasm Staging; D016019:Survival Analysis
chemical_list: D000911:Antibodies, Monoclonal; D018906:Antineoplastic Agents, Alkylating; D000074324:Ipilimumab; D003606:Dacarbazine