alendronate, Fosamax
Pharmacological treatment of osteopenia induced by gastrectomy or ovariectomy in young female rats.

Andersson N, Surve VV, Lehto-Axtelius D, Andersson K, Ryberg B, Ohlsson C, Hakanson R.

Department of Pharmacology, Institute of Physiological Sciences, Lund University, BMC F-13, SE-221 84 Lund.

BACKGROUND: Both gastrectomy (GX) and ovariectomy (OVX) induce osteopenia in man and experimental animals. The present study addresses the question--can alendronate, estrogen or parathyroid hormone (PTH) be used to treat established GX- or OVX -evoked osteopenia? METHODS: Rats were GX-, OVX- or SHAM-operated 8 weeks before starting the treatment with drugs. Each group was then treated for 8 weeks with 50 microg/kg/day alendronate, 10 microg/kg/day estrogen or 75 microg/kg/day PTH(1-84); n = 8 rats/group. Peripheral Quantitative Computed Tomography (pQCT) was used to measure trabecular bone mineral density (BMD) and various cortical bone parameters. RESULTS: At killing, 16 weeks after surgery, GX and OVX rats had a greatly reduced trabecular BMD in the metaphysis of the distal femur (GX -44% and OVX -55%). Alendronate increased the trabecular BMD by 44% in GX rats and by 64% in OVX rats, while PTH increased it by 51% and 115%, respectively. However, estrogen increased the trabecular BMD in GX rats (35%), but not in OVX rats (15%, not significant). Cortical bone parameters were adversely (but moderately) affected by GX, but not by OVX or by treatment with the three drugs. INTERPRETATION: Alendronate, estrogen and PTH restored the trabecular bone loss in rats with an established GX-evoked osteopenia. In contrast, alendronate and PTH, but not estrogen, restored the trabecular bone loss after OVX. Hence, the mechanism underlying GX-evoked bone loss differs from that underlying OVX-evoked bone loss. The ability of alendronate, estrogen and PTH to reverse the GX-evoked osteopenia in the rat may be of clinical interest when dealing with bone loss in humans after GX.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15180236&dopt=Abstract alendronate Fosamax



alendronate, Fosamax
Cost effectiveness of alendronate for the treatment of male osteoporosis in Sweden.

Borgstrom F, Johnell O, Jonsson B, Zethraeus N, Sen SS.

Stockholm Health Economics, Sweden. frederick.b healtheconomics.se

BACKGROUND: One third of all the hip fractures occur in men. The risk for mortality following hip fracture is higher for men compared to women. The Fracture Intervention Trial (FIT) showed that the bisphosphonate alendronate reduces the risk of fractures and increases bone mineral density (BMD) in osteoporotic women. Similar effects of alendronate were observed in men in some other trials. There are also results demonstrating alendronate to be cost-effective in the treatment of osteoporosis in women. OBJECTIVE: To investigate the cost effectiveness of alendronate for male osteoporosis in Sweden by assuming the same relative risk reduction of fractures in men as for women, based on the FIT trial. DESIGN: A Markov model earlier used to analyze cost effectiveness of alendronate in treatment of postmenopausal osteoporosis in Sweden was adapted to fit a cohort of Swedish men. Cost effectiveness of alendronate vs. no treatment was assessed by transitioning men in the model over time between different health states. TIME HORIZON: The patients were followed from start of intervention until 100 years of age or death. In the base-case alendronate was assumed to have a fracture-risk-reducing effect for 10 years; a treatment duration period of 5 years followed by a 5-year period where the effect declined linearly to zero. RESULTS: Taking a societal perspective treating a 71-year-old man (mean age in the FIT) with low BMD and prior vertebral fracture (VFA) with alendronate was found to be associated with a cost of 14,843 per quality adjusted life year (QALY) gained. CONCLUSIONS: The results in this study indicate that treating osteoporotic men with alendronate was projected to be cost-effective, under the assumption of the same fracture-risk-reducing effect of alendronate for men as for women.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15193554&dopt=Abstract alendronate Fosamax



alendronate, Fosamax
Change in bone turnover and hip, non-spine, and vertebral fracture in alendronate-treated women: the fracture intervention trial.

Bauer DC, Black DM, Garnero P, Hochberg M, Ott S, Orloff J, Thompson DE, Ewing SK, Delmas PD; Fracture Intervention Trial Study Group.

Department of Medicine, Epidemiology and Biostatistics, University of California, San Francisco, California 94105, USA. dbauer psf.ucsf.edu

We used data from the Fracture Intervention Trial to assess the relationship change in bone turnover after 1 year of alendronate or placebo treatment and subsequent hip, non-spine, and spine fracture risk among 6186 postmenopausal women. In the alendronate group (n = 3105), greater reductions in one or more biochemical marker were associated with a lower risk of fracture. INTRODUCTION: There are few data on the relationship between short-term change in biochemical markers of bone turnover and non-spine fracture risk among bisphosphonate-treated women, and the clinical use of such measurements is unknown. MATERIALS AND METHODS: We measured biochemical markers of bone turnover (bone-specific alkaline phosphatase [bone ALP], intact N-terminal propeptide of type I collagen, and C-terminal crosslinked telopeptide of type 1 collagen) and BMD of the spine and hip at baseline and after 1 year of alendronate or placebo. During a mean follow-up of 3.6 years, 72 hip, 786 non-spine, and 336 vertebral fractures were documented. RESULTS AND CONCLUSIONS: Each 1 SD reduction in 1-year change in bone ALP was associated with fewer spine (odds ratio = 0.74; CI: 0.63, 0.87), non-spine (relative hazard [RH] = 0.89; CI: 0.78, 1.00; p < 0.050), and hip fractures (RH = 0.61; CI: 0.46, 0.78). Alendronate-treated women with at least a 30% reduction in bone ALP had a lower risk of non-spine (RH = 0.72; CI: 0.55, 0.92) and hip fractures (RH = 0.26; CI: 0.08, 0.83) relative to those with reductions <30%. We conclude that greater reductions in bone turnover with alendronate therapy are associated with fewer hip, non-spine, and vertebral fractures, and the effect is at least as strong as that observed with 1-year change in BMD.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15231011&dopt=Abstract alendronate Fosamax



alendronate, Fosamax
Raloxifene, estrogen, and alendronate affect the processes of fracture repair differently in ovariectomized rats.

Cao Y, Mori S, Mashiba T, Westmore MS, Ma L, Sato M, Akiyama T, Shi L, Komatsubara S, Miyamoto K, Norimatsu H.

Department of Orthopedic Surgery, Kagawa Medical University, Kagawa, Japan.

We investigated the effects of inhibitors of bone resorption (estrogen, raloxifene, and alendronate) on the processes of fracture repair in ovariectomized (OVX) rats. One hundred forty female Sprague-Dawley rats at 3 months of age were either OVX or sham-operated and divided into five groups: sham control, OVX control, estrogen (17alpha-ethynyl estradiol [EE2], 0.1 mg/kg), raloxifene (Rlx, 1.0 mg/kg), and alendronate (Aln, 0.01 mg/kg) groups. Treatment began immediately after the surgery. Four weeks postovariectomy, prefracture controls were killed and bilateral osteotomies were performed on the femoral midshafts and fixed with intramedullary wires. Treatment was continued and fracture calluses were excised at 6 weeks and 16 weeks postfracture for evaluation by X-ray radiography, quantitative computed tomography (QCT,) biomechanical testing, and histomorphometry. At 6 weeks postfracture, Aln and OVX had larger calluses than other groups. Sham and OVX had higher ultimate load than EE2 and Rlx, with Aln not different from either control. Aln calluses also contained more mineral (bone mineral content [BMC]) than all other groups. By 16 weeks postfracture, OVX calluses were smaller than at 6 weeks and the dimensions for Aln had not changed. Aln had higher BMC and ultimate load than OVX, EE2, and Rlx. EE2 and Rlx had similar biomechanical properties, which were similar to sham. Interestingly, OVX and Aln animals were heavier than other groups at all time points; therefore, ultimate load was normalized by body weight to show no significant differences in strength of the whole callus between groups at either 6 weeks or 16 weeks postfracture. However, Aln strongly suppressed remodeling of the callus, resulting in the highest content of woven bone, persistent visibility of the original fracture line, and lowest content of lamellar bone, compared with other groups. Therefore, the larger Aln callus appeared to be a remarkable, morphological adaptation to secure the fracture with inferior material. In conclusion, OVX-stimulated bone turnover resulted in the fastest progression of fracture repair that was most delayed with Aln treatment, consistent with marked suppression of bone resorption and formation activity. Estrogen and Rlx had similar effects that were generally similar to sham, indicating that mild suppression of bone turnover with these agents has insignificant effects on the progression of fracture repair.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12469918&dopt=Abstract alendronate Fosamax



alendronate, Fosamax
Randomized trial of effect of alendronate continuation versus discontinuation in women with low BMD: results from the Fracture Intervention Trial long-term extension.

Ensrud KE, Barrett-Connor EL, Schwartz A, Santora AC, Bauer DC, Suryawanshi S, Feldstein A, Haskell WL, Hochberg MC, Torner JC, Lombardi A, Black DM; Fracture Intervention Trial Long-Term Extension Research Group.

Department of Medicine, VA Medical Center, Minneapolis, Minnesota 55417, USA. Ensru001 umn.edu

To determine the effects of continuation versus discontinuation of alendronate on BMD and markers of bone turnover, we conducted an extension trial in which 1099 older women who received alendronate in the FIT were re-randomized to alendronate or placebo. Compared with women who stopped alendronate, those continuing alendronate for 3 years maintained a higher BMD and greater reduction of bone turnover, showing benefit of continued treatment. However, among women who discontinued alendronate and took placebo in the extension, BMD remained higher, and reduction in bone turnover was greater than values at FIT baseline, showing persistence of alendronate's effects on bone. INTRODUCTION: Prior trials including the Fracture Intervention Trial (FIT) have found that therapy with alendronate increases BMD and decreases fracture risk for up to 4 years in postmenopausal women with low BMD. However, it is uncertain whether further therapy with alendronate results in preservation or further gains in BMD and if skeletal effects of alendronate continue after treatment is stopped. MATERIALS AND METHODS: We conducted a follow-up placebo-controlled extension trial to FIT (FIT long-term extension [FLEX]) in which 1099 women 60-86 years of age who were assigned to alendronate in FIT with an average duration of use of 5 years were re-randomized for an additional 5 years to alendronate or placebo. The results of a preplanned interim analysis at 3 years are reported herein. Participants were re-randomized to alendronate 10 mg/day (30%), alendronate 5 mg/day (30%), or placebo (40%). All participants were encouraged to take a calcium (500 mg/day) and vitamin D (250 IU/day) supplement. The primary outcome was change in total hip BMD. Secondary endpoints included change in lumbar spine BMD and change in markers of bone turnover (bone-specific alkaline phosphatase and urinary type I collagen cross-linked N-telopeptide). RESULTS: Among the women who had prior alendronate therapy in FIT, further therapy with alendronate (5 and 10 mg groups combined) for 3 years compared with placebo maintained BMD at the hip (2.0% difference; 95% CI, 1.6-2.5%) and further increased BMD at the spine (2.5% difference; 95% CI, 1.9-3. 1%). Markers of bone turnover increased among women discontinuing alendronate, whereas they remained stable in women continuing alendronate. Cumulative increases in BMD at the hip and spine and reductions in bone turnover from 8.6 years earlier at FIT baseline were greater for women continuing alendronate compared with those discontinuing alendronate. However, among women discontinuing alendronate and taking placebo in the extension, BMD remained higher and reduction in bone turnover was greater than values at FIT baseline. CONCLUSIONS: Compared with women who stopped alendronate after an average of 5 years, those continuing alendronate maintained a higher BMD and greater reduction of bone turnover, showing benefit of continued alendronate treatment on BMD and bone turnover. On discontinuation of alendronate therapy, rates of change in BMD at the hip and spine resumed at the background rate, but discontinuation did not result in either accelerated bone loss or a marked increase in bone turnover, showing persistence of alendronate's effects on bone. Data on the effect of continuation versus discontinuation on fracture risk are needed before making definitive recommendations regarding the optimal length of alendronate treatment.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15231012&dopt=Abstract alendronate Fosamax



alendronate, Fosamax
Healing properties of allograft from alendronate-treated animal in lumbar spine interbody cage fusion.

Xue Q, Li H, Zou X, Bunger M, Egund N, Lind M, Christensen FB, Bunger C.

Orthopedic Department E., Spine Section, Orthopedic Research Laboratory, Institute for Experimental Clinical Research. Aarhus University Hospital, Denmark.

This study investigated the healing potential of allograft from bisphosphonate-treated animals in anterior lumbar spine interbody fusion. Three levels of anterior lumbar interbody fusion with Brantigan cages were performed in two groups of five landrace pigs. Empty Brantigan cages or cages filled with either autograft or allograft were located randomly at different levels. The allograft materials for the treatment group were taken from the pigs that had been fed with alendronate, 10 mg daily for 3 months. The histological fusion rate was 2/5 in alendronate-treated allograft and 3/5 in non-treated allograft. The mean bone volume was 39% and 37.2% in alendronate-treated or non-treated allograft (NS), respectively. No statistical difference was found between the same grafted cage comparing two groups. The histological fusion rate was 7/10 in all autograft cage levels and 5/10 in combined allograft cage levels. No fusion was found at all in empty cage levels. With the numbers available, no statistically significant difference was found in histological fusion between autograft and allograft applications. There was a significant difference of mean bone volume between autograft (49.2%) and empty cage (27.5%) ( P<0.01). In conclusion, this study did not demonstrate different healing properties of alendronate-treated and non-treated allograft for anterior lumbar interbody fusion in pigs.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15248057&dopt=Abstract alendronate Fosamax