Comparison of weekly treatment of postmenopausal osteoporosis with alendronate versus risedronate over two years.
OBJECTIVE
A 1-yr extension of the Fosamax Actonel Comparison Trial was completed to compare changes in bone mineral density (BMD), bone turnover, and upper gastrointestinal tolerability over 2 yr of treatment.


METHODS
This was a randomized, double-blind extension conducted at 72 U.S. sites.


METHODS
Of the 1053 women who completed yr 1, 833 postmenopausal women with low BMD entered the extension, continuing their same treatment allocation [once-weekly (OW) alendronate 70 mg or OW risedronate 35 mg]. Changes in BMD at the hip trochanter, total hip, femoral neck, and lumbar spine and in markers of bone turnover were compared at 24 months. Tolerability was assessed by adverse experience reporting.


RESULTS
Alendronate produced greater increases from baseline in BMD at 24 months than did risedronate at the trochanter (alendronate, 4.6%; risedronate, 2.5%, P < 0.001) as well as at all other BMD sites. Significantly more alendronate than risedronate patients had measured BMD increases of 0% or more and 3% or more at all BMD sites (P < 0.001), and fewer alendronate patients had measured decreases of 3% or more at all BMD sites. Significantly greater reductions in all biochemical markers of bone turnover occurred with alendronate, compared with risedronate. No differences were seen in occurrence or discontinuations due to upper gastrointestinal adverse experiences.


CONCLUSIONS
Patients receiving 70 mg OW alendronate had greater gains in BMD, were more likely to maintain or gain BMD, and had greater reductions in bone turnover markers than patients receiving 35 mg OW risedronate after 24 months, with no differences in upper gastrointestinal tolerability.
Bonnick
Sydney
S
Clinical Research Center of North Texas, 2921 Country Club Road, Suite 101, Denton, Texas 76210, USA. sbonnick@msn.com
Saag
Kenneth G
KG
Kiel
Douglas P
DP
McClung
Michael
M
Hochberg
Marc
M
Burnett
Sherri-Ann M
SM
Sebba
Anthony
A
Kagan
Risa
R
Chen
Erluo
E
Thompson
Desmond E
DE
de Papp
Anne E
AE
D000368:Aged; D019386:Alendronate / Q000008:administration & dosage* / Q000009:adverse effects; D015519:Bone Density; D016723:Bone Remodeling; D004311:Double-Blind Method; D012968:Etidronic Acid / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D005260:Female; D005269:Femur; D005272:Femur Neck; D050723:Fractures, Bone / Q000453:epidemiology; D006801:Humans; D008159:Lumbar Vertebrae; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy*; D000068296:Risedronic Acid; D016896:Treatment Outcome
D000068296:Risedronic Acid; D012968:Etidronic Acid; D019386:Alendronate