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

Osteoporos Int. 2013 Apr;24(4):1503-11. doi: 10.1007/s00198-012-2098-3. Epub 2012 Aug 29.

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.

Introduction: 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.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged, 80 and over
  • Biomarkers / blood
  • Bone Density / drug effects*
  • Bone Density Conservation Agents / administration & dosage*
  • Bone Density Conservation Agents / adverse effects
  • Bone Density Conservation Agents / therapeutic use
  • Bone Remodeling / drug effects
  • Double-Blind Method
  • Female
  • Femur Neck / physiopathology
  • Follow-Up Studies
  • Hip Joint / physiopathology
  • Humans
  • Lumbar Vertebrae / physiopathology
  • Medication Adherence / statistics & numerical data*
  • Middle Aged
  • Osteoporosis, Postmenopausal / drug therapy*
  • Osteoporosis, Postmenopausal / physiopathology
  • Osteoporotic Fractures / prevention & control
  • Parathyroid Hormone / administration & dosage*
  • Parathyroid Hormone / adverse effects
  • Parathyroid Hormone / therapeutic use
  • Radius / physiopathology
  • Recombinant Proteins / administration & dosage
  • Recombinant Proteins / adverse effects
  • Recombinant Proteins / therapeutic use
  • Spinal Fractures / prevention & control
  • Treatment Outcome

Substances

  • Biomarkers
  • Bone Density Conservation Agents
  • Parathyroid Hormone
  • Recombinant Proteins