title: A novel adaptive design strategy increases the efficiency of clinical trials in secondary progressive multiple sclerosis.
abstract: BACKGROUND
  Adaptive seamless designs (ASDs) have been proposed to test multiple candidate compounds using an interim decision point which allows potentially effective therapies to be taken into the next design stage and to be assessed using a phase III outcome.
  
  
  OBJECTIVE
  To determine whether ASDs are feasible in secondary progressive multiple sclerosis (SPMS) and to compare them with conventional trial designs.
  
  
  METHODS
  We develop an innovative adaptive trial design for SPMS, which builds on recent developments in statistical methodology. A literature search and individual clinical datasets were used to inform a framework to run simulations to evaluate the proposed design.
  
  
  RESULTS
  ASDs are feasible in SPMS with MRI informing an interim decision point and Expanded Disability Status Scale (EDSS) as the final disability endpoint. Furthermore ASDs are more efficient than conventional designs with sample size savings of up to 40%. Sample sizes of 1000-1250 patients are sufficient to test up to four experimental treatments. Controlled recruitment is important to realize the full benefits of ASDs.
  
  
  CONCLUSIONS
  Although more complex in design, ASDs have the potential to be more efficient and more powerful than conventional designs.
authors.affiliation: National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, Queen Square, London, UK.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Chataway
authors.forename: Richard
authors.initials: R
authors.lastname: Nicholas
authors.forename: Susan
authors.initials: S
authors.lastname: Todd
authors.forename: David H
authors.initials: DH
authors.lastname: Miller
authors.forename: Nicholas
authors.initials: N
authors.lastname: Parsons
authors.forename: Elsa
authors.initials: E
authors.lastname: Valdés-Márquez
authors.forename: Nigel
authors.initials: N
authors.lastname: Stallard
authors.forename: Tim
authors.initials: T
authors.lastname: Friede
mesh_terms: D015415:Biomarkers / Q000032:analysis; D002986:Clinical Trials as Topic / Q000379:methods* / Q000706:statistics & numerical data; D017322:Clinical Trials, Phase II as Topic / Q000379:methods; D017326:Clinical Trials, Phase III as Topic / Q000379:methods; D003198:Computer Simulation; D003627:Data Interpretation, Statistical; D004185:Disability Evaluation; D023381:Endpoint Determination; D005240:Feasibility Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D020528:Multiple Sclerosis, Chronic Progressive / Q000175:diagnosis / Q000188:drug therapy*; D011237:Predictive Value of Tests; D016032:Randomized Controlled Trials as Topic / Q000379:methods; D012107:Research Design / Q000706:statistics & numerical data; D018401:Sample Size; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers