title: Novel strategies for improving physical function.
abstract: BACKGROUND
  The number of elderly people is growing worldwide, and a substantial proportion of them report difficulty with mobility and in performing activities of daily living. The demographic trends have created enormous interest in development of function-promoting anabolic therapies. At present, androgens and myostatin inhibitors are the two leading classes of function-promoting anabolic therapies that are the most advanced in the drug development process. However, clinical development has been slowed by vexing trial design issues.
  
  
  CONCLUSIONS
  Clinical investigators, regulatory agencies and the National Institutes of Health must continue working toward a consensus about the indications for study, efficacy outcomes and what differences in functional outcomes are needed to determine sample size estimates.
authors.affiliation: Section of Endocrinology, Diabetes and Nutrition, Boston University School of Medicine and Boston Medical Center, Boston, MA 02118, USA. bhasin@bu.edu
authors.forename: Shalender
authors.initials: S
authors.lastname: Bhasin
authors.forename: Ravi
authors.initials: R
authors.lastname: Jasuja
authors.forename: Powen
authors.initials: P
authors.lastname: Tu
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Storer
authors.forename: Wen
authors.initials: W
authors.lastname: Guo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000187:drug effects; D045930:Anabolic Agents / Q000627:therapeutic use*; D000728:Androgens / Q000627:therapeutic use*; D000818:Animals; D001823:Body Composition / Q000187:drug effects; D002986:Clinical Trials as Topic / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology*; D055435:Myostatin / Q000037:antagonists & inhibitors*; D013739:Testosterone / Q000627:therapeutic use
chemical_list: D045930:Anabolic Agents; D000728:Androgens; C525911:MSTN protein, human; D055435:Myostatin; D013739:Testosterone