The effects of strontium ranelate on the risk of vertebral fracture in women with postmenopausal osteoporosis.
BACKGROUND
Osteoporotic structural damage and bone fragility result from reduced bone formation and increased bone resorption. In a phase 2 clinical trial, strontium ranelate, an orally active drug that dissociates bone remodeling by increasing bone formation and decreasing bone resorption, has been shown to reduce the risk of vertebral fractures and to increase bone mineral density.


METHODS
To evaluate the efficacy of strontium ranelate in preventing vertebral fractures in a phase 3 trial, we randomly assigned 1649 postmenopausal women with osteoporosis (low bone mineral density) and at least one vertebral fracture to receive 2 g of oral strontium ranelate per day or placebo for three years. We gave calcium and vitamin D supplements to both groups before and during the study. Vertebral radiographs were obtained annually, and measurements of bone mineral density were performed every six months.


RESULTS
New vertebral fractures occurred in fewer patients in the strontium ranelate group than in the placebo group, with a risk reduction of 49 percent in the first year of treatment and 41 percent during the three-year study period (relative risk, 0.59; 95 percent confidence interval, 0.48 to 0.73). Strontium ranelate increased bone mineral density at month 36 by 14.4 percent at the lumbar spine and 8.3 percent at the femoral neck (P<0.001 for both comparisons). There were no significant differences between the groups in the incidence of serious adverse events.


CONCLUSIONS
Treatment of postmenopausal osteoporosis with strontium ranelate leads to early and sustained reductions in the risk of vertebral fractures.
Meunier
Pierre J
PJ
Department of Rheumatology and Bone Diseases, Edouard Herriot Hospital, Lyons, France. pierre.meunier@laennec.univ-lyon1.fr
Roux
Christian
C
Seeman
Ego
E
Ortolani
Sergio
S
Badurski
Janusz E
JE
Spector
Tim D
TD
Cannata
Jorge
J
Balogh
Adam
A
Lemmel
Ernst-Martin
EM
Pors-Nielsen
Stig
S
Rizzoli
René
R
Genant
Harry K
HK
Reginster
Jean-Yves
JY
D000284:Administration, Oral; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001706:Biopsy; D015519:Bone Density / Q000187:drug effects; D001842:Bone and Bones / Q000378:metabolism / Q000473:pathology; D002118:Calcium / Q000627:therapeutic use; D017326:Clinical Trials, Phase III as Topic; D004311:Double-Blind Method; D005260:Female; D005272:Femur Neck; D005598:Fractures, Spontaneous / Q000517:prevention & control; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries; D008875:Middle Aged; D009942:Organometallic Compounds / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D015663:Osteoporosis, Postmenopausal / Q000150:complications / Q000188:drug therapy*; D011446:Prospective Studies; D011859:Radiography; D012306:Risk; D055502:Secondary Prevention; D016103:Spinal Fractures / Q000209:etiology / Q000517:prevention & control*; D013324:Strontium / Q000097:blood; D013876:Thiophenes / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries; D016896:Treatment Outcome
D015415:Biomarkers; D009942:Organometallic Compounds; D013876:Thiophenes; C081587:strontium ranelate; D002118:Calcium; D013324:Strontium