Effects of abaloparatide-SC (BA058) on bone histology and histomorphometry: The ACTIVE phase 3 trial

Bone. 2017 Apr;97:314-319. doi: 10.1016/j.bone.2016.11.004. Epub 2016 Nov 5.

Abstract

There are a number of effective treatments for osteoporosis but most are in the antiresorptive class of compounds. Abaloparatide-SC is a new osteoanabolic agent, which increased bone mineral density and lowered the risk of osteoporosis-related fractures in the phase 3 ACTIVE trial. The objective of this report is to describe the effects of abaloparatide-SC 80μg on bone histology and histomorphometry in iliac crest bone biopsies from this trial in which participants were randomized to receive blinded daily subcutaneous injections of placebo or abaloparatide-SC 80μg/d or open-label teriparatide 20μg/d for 18months. Iliac crest bone biopsies were obtained between 12 and 18months. Qualitative histological analysis of biopsies from abaloparatide-SC-treated patients revealed normal bone microarchitecture without evidence of adverse effects on mineralization or on the formation of normal lamellar bone. There were no bone marrow abnormalities, marrow fibrosis nor was there presence of excess osteoid or woven bone. There were few significant differences among the three treatment groups in a standard panel of static and dynamic histomorphometric indices. The mineral apposition rate was higher in the teriparatide-treated group than in the placebo-treated group. The eroded surface was lower in the abaloparatide-SC-treated group than in the placebo-treated group. Cortical porosity was higher in both the abaloparatide-SC- and the teriparatide-treated groups than in the placebo-treated group. We conclude that histological and histomorphometric analysis of iliac crest bone biopsies from subjects who were treated for up to 18months with abaloparatide-SC showed no evidence of concern for bone safety.

Trial registration: ClinicalTrials.gov number NCT01343004.

Keywords: Abaloparatide; Bone; Histology; Histomorphometry; Osteoporosis.

Publication types

  • Clinical Trial, Phase III
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Biopsy
  • Bone Density
  • Bone and Bones / drug effects*
  • Bone and Bones / pathology*
  • Cohort Studies
  • Demography
  • Female
  • Humans
  • Middle Aged
  • Parathyroid Hormone-Related Protein / pharmacology*

Substances

  • Parathyroid Hormone-Related Protein
  • abaloparatide

Associated data

  • ClinicalTrials.gov/NCT01343004