title: Improved adherence with PTH(1-84) in an extension trial for 24 months results in enhanced BMD gains in the treatment of postmenopausal women with osteoporosis.
abstract: The purpose of this study is to examine the effect of PTH(1-84) treatment over 24 months followed by 12 months discontinuation on BMD, bone turnover markers, fractures and the impact of adherence on efficacy.
  
  
  BACKGROUND
  There is limited information about the effect of PTH(1-84) after 18 months and limited data about the impact of compliance on response to anabolic therapy.
  
  
  METHODS
  Seven hundred and eighty-one subjects who received active PTH(1-84) in the Treatment of Osteoporosis with Parathyroid hormone trial for approximately 18 months were entered into a 6-month open-label extension. Thereafter, they were followed for 12 additional months after discontinuation of treatment. Endpoints examined included changes in BMD and biochemical markers.
  
  
  RESULTS
  PTH(1-84) treatment over 24 months increased BMD at the lumbar spine by 6.8% above baseline (p<0.05).The total corresponding BMD increases at the hip and femoral neck were 1.1 and 2.2% above baseline. Larger increases in spine BMD were observed in participants with ≥80% adherence to daily injections of PTH(1-84) (8.3% in adherent vs 4.9% in poorly adherent patients). Total hip BMD gains were 1.7% in adherent vs 0.6% in poorly adherent participants. Markers of bone turnover (BSAP and NTx) peaked 6 months after starting PTH(1-84) treatment and declined slowly but remained above baseline at 24 months. After discontinuation of PTH(1-84) treatment (at 24 months), bone turnover markers returned to near baseline levels by 30 months. The adherent group sustained significantly fewer fractures than the poorly adherent group.
  
  
  CONCLUSIONS
  PTH(1-84) treatment over 24 months results in continued increases in lumbar spine BMD. Adherence to treatment with PTH(1-84) for up to 24 months is also associated with greater efficacy.
authors.affiliation: Department of Epidemiology and Biostatistics, University of California, San Fransisco, Suite 5700, 185 Berry Street, San Francisco, CA 94107, USA. dblack@psg.ucsf.edu
authors.forename: D M
authors.initials: DM
authors.lastname: Black
authors.forename: J P
authors.initials: JP
authors.lastname: Bilezikian
authors.forename: S L
authors.initials: SL
authors.lastname: Greenspan
authors.forename: C
authors.initials: C
authors.lastname: Wüster
authors.forename: M
authors.initials: M
authors.lastname: Muñoz-Torres
authors.forename: H G
authors.initials: HG
authors.lastname: Bone
authors.forename: C J
authors.initials: CJ
authors.lastname: Rosen
authors.forename: H S
authors.initials: HS
authors.lastname: Andersen
authors.forename: D A
authors.initials: DA
authors.lastname: Hanley
mesh_terms: D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D015519:Bone Density / Q000187:drug effects*; D050071:Bone Density Conservation Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D016723:Bone Remodeling / Q000187:drug effects; D004311:Double-Blind Method; D005260:Female; D005272:Femur Neck / Q000503:physiopathology; D005500:Follow-Up Studies; D006621:Hip Joint / Q000503:physiopathology; D006801:Humans; D008159:Lumbar Vertebrae / Q000503:physiopathology; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy* / Q000503:physiopathology; D058866:Osteoporotic Fractures / Q000517:prevention & control; D010281:Parathyroid Hormone / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D011884:Radius / Q000503:physiopathology; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D016103:Spinal Fractures / Q000517:prevention & control; D016896:Treatment Outcome; D016903:Drug Monitoring
chemical_list: D015415:Biomarkers; D050071:Bone Density Conservation Agents; D010281:Parathyroid Hormone; D011994:Recombinant Proteins