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. DESIGN: This was a randomized, double-blind extension conducted at 72 U.S. sites. PATIENTS AND 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.

Effect of alendronate on the age-specific incidence of symptomatic osteoporotic fractures.

UNLABELLED: Analyses of data from 3658 postmenopausal women with osteoporosis enrolled in the Fracture Intervention Trial showed that alendronate is effective in reducing the risk of symptomatic osteoporotic fractures across a spectrum of ages. INTRODUCTION: Most osteoporosis studies examine the relative risk of fracture based on the entire duration of treatment. Because older patients tend to be at higher risk for osteoporosis-related fractures, this analysis examined the effect of alendronate treatment on the relative risk of fracture in terms of the age that patients attained during the study. MATERIALS AND METHODS: We studied 3658 postmenopausal women with osteoporosis 55-80 years of age at baseline enrolled in the Fracture Intervention Trial, a large randomized, double-blind, placebo-controlled study. Patients were treated with placebo or with alendronate at a daily dose of 5 mg for 2 years followed by 10 mg for an additional 1-2.5 years, and monitored for clinical fractures. Age, rather than study time, was the dynamic variable in our analysis. RESULTS: The relative risk reductions for hip, clinical spine, and wrist fractures were constant across age groups, without evidence of a decline at older ages. Specifically, alendronate reduced the risk of clinical fracture by 53% at the hip (relative risk [RR] = 0.47; 95% CI = 0.27-0.81; p < 0.01), 45% at the spine (RR = 0.55; 95% CI = 0.37-0.83; p < 0.01), and 31% at the wrist (RR = 0.69; 95% CI = 0.50-0.98; p = 0.038). In addition, alendronate produced a significant risk reduction of 40% (RR = 0.60; 95% CI = 0.47-0.77; p < 0.01) for the composite event of clinical hip, spine, and wrist fractures. As a consequence of the constant relative risk model, the absolute risk reduction with alendronate treatment increased with age because of the age-related increase in fracture risk in the placebo group. The absolute risk reduction for the composite event (hip, spine, and wrist fractures together) for alendronate treatment versus placebo was 65, 80, 111, and 161 women with fractures per 10,000 PYR for the 55 to <65, 65 to <70, 70 to <75, and 75-85 year age groups, respectively. CONCLUSIONS: These data show that alendronate is effective in reducing the risk of symptomatic osteoporotic fractures across a spectrum of ages. The effectiveness is somewhat greater in patients with femoral neck T score < or = -2.5 than in those with a T score < or = -2.0.

Effect of alendronate on vertebral fracture risk in women with bone mineral density T scores of-1.6 to -2.5 at the femoral neck: the Fracture Intervention Trial.

OBJECTIVES: To determine the efficacy of alendronate treatment on risk of vertebral fracture in a subgroup of women from the Fracture Intervention Trial who had bone mineral density T scores between -1.6 and -2.5 at the femoral neck and to describe how soon after initiation of therapy alendronate becomes effective and whether it is consistent in women with and without existing radiographic vertebral fracture. PATIENTS AND METHODS: From May 1992 to March 1997, postmenopausal women aged 55 to 80 years were randomized to receive alendronate at 5 mg/d for 2 years and 10 mg/d thereafter or placebo for up to 4.5 years (mean, 3.8 years) in a controlled, double-blind, multicenter study. RESULTS: A total of 3737 postmenopausal women were included in the study, 1878 in the alendronate group and 1859 in the placebo group. Risk of vertebral fracture was significantly reduced by alendronate compared with placebo for clinical (relative risk [RR], 0.40; 95% confidence interval [CI], 0.19-0.76; P=.005) and radiographic (RR, 0.57; 95% CI, 0.41-0.81; P=-.002) fracture. The reductions in vertebral fracture risk were consistent in women with and without an existing radiographic vertebral fracture for clinical (RR, 0.34; 95% CI, 0.12-0.84; and RR, 0.46; 95% CI, 0.16-1.17; respectively) and radiographic (RR, 0.53; 95% CI, 0.34-0.82; and RR, 0.64; 95% CI, 0.38-1.10; respectively) fractures. In both groups, the effect of alendronate on clinical vertebral fracture was noted soon after therapy was initiated. The absolute risk of vertebral fracture was low in women without a baseline radiographic fracture. CONCLUSIONS: In women with low bone mass who do not meet the bone mineral density criterion for osteoporosis, alendronate is effective in reducing the risk of vertebral fractures. The absolute benefit of this therapy in women with a T score between -1.6 and -2.5 is greater in women with an existing vertebral fracture and/or with other risk factors. The effect of alendronate occurs early.

Meta-analysis of the efficacy of alendronate for the prevention of hip fractures in postmenopausal women.

Treatment with alendronate, a potent and specific inhibitor of bone resorption, is known to significantly reduce fracture risk among women with postmenopausal osteoporosis. The purpose of this meta-analysis was to assess the consistency of the effect of alendronate in reducing the risk of hip fracture among different studies and populations. Data from completed, randomized, treatment studies were pooled in a meta-analysis. The duration of the studies ranged from 1-4.5 years. The dose of alendronate ranged from 5-20 mg/day, with over 95% of patients receiving either 5 or 10 mg/day during the trials. In patients with a T-score of less than or equal to -2.0, or with a vertebral fracture, the effect on hip fracture risk consistently favored patients receiving alendronate therapy, with an overall reduction in risk of hip fracture of 45% [95% confidence interval (CI) 16% to 64%, P=0.007]. For patients who met the criteria of osteoporosis, as defined by the World Health Organization (WHO), the overall risk reduction was 55% (95% CI 29% to 72%, P=0.0008). In both analyses we performed a sensitivity analysis by removing one study at a time. The strength of the evidence was not dependent on any one study. We conclude that therapy with alendronate is associated with significant and clinically important reductions in the incidence of hip fracture in women with postmenopausal osteoporosis. The overall reduction is consistent among different patient populations.

Treatment with once-weekly alendronate 70 mg compared with once-weekly risedronate 35 mg in women with postmenopausal osteoporosis: a randomized double-blind study.

UNLABELLED: Once-weekly alendronate 70 mg and once-weekly risedronate 35 mg are indicated for the treatment of postmenopausal osteoporosis. These two agents were compared in a 12-month head-to-head trial. Greater gains in BMD and greater reductions in markers of bone turnover were seen with alendronate compared with risedronate with similar tolerability. INTRODUCTION: The nitrogen-containing bisphosphonates, alendronate and risedronate, are available in once-weekly (OW) formulations for the treatment of postmenopausal osteoporosis. A 12-month, head-to-head study was performed to compare these agents in the treatment of postmenopausal women with low BMD. MATERIALS AND METHODS: A total of 1053 patients from 78 U.S. sites were randomized to OW alendronate 70 mg (N = 520) or risedronate 35 mg (N = 533), taken in the morning after fasting. Endpoints included BMD changes over 6 and 12 months at the hip trochanter, total hip, femoral neck, and lumbar spine (LS); percent of patients with predefined levels of change in trochanter and LS BMD at 12 months; and change in biochemical markers of bone turnover at 3, 6, and 12 months. Tolerability was evaluated by adverse experience (AE) reporting. RESULTS: Significantly greater increases in hip trochanter BMD were seen with alendronate (3.4%) than risedronate (2.1%) at 12 months (treatment difference, 1.4%; p < 0.001) as well as 6 months (treatment difference, 1.3%; p < 0.001). Significantly greater gains in BMD were seen with alendronate at all BMD sites measured (12-month difference: total hip, 1.0%; femoral neck, 0.7%; LS, 1.2%). Significant differences were seen as early as 6 months at all sites. A greater percentage of patients had > or =0% (p < 0.001) and > or =3% (p < 0.01) gain in trochanter and spine BMD at 12 months with alendronate than risedronate. Significantly greater (p < 0.001) reductions in all biochemical markers of bone turnover occurred with alendronate compared with risedronate by 3 months. No significant differences were seen between treatment groups in the incidence of upper gastrointestinal AEs or AEs causing discontinuation. CONCLUSIONS: In this 12-month, head-to-head trial of alendronate and risedronate, given in accordance with the approved OW regimens for treatment of osteoporosis in postmenopausal women, alendronate produced greater gains in BMD and greater reductions in markers of bone turnover than risedronate. The greater antiresorptive effect of alendronate was seen as early as 3 months, and the tolerability profiles were similar.

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

UNLABELLED: 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.

Response to therapy with once-weekly alendronate 70 mg compared to once-weekly risedronate 35 mg in the treatment of postmenopausal osteoporosis.

OBJECTIVE: The FACT study (Fosamax Actonel Comparison Trial) was a 1-year-head-to-head trial comparing the efficacy and tolerability of once weekly (DW) alendronate 70 mg and OW risedronate 35 mg for the treatment of postmenopausal osteoporosis. The present analysis was performed to determine the percentage of patients who had changes during the study in BMD and biochemical markers (BCMs) of bone turnover above or below specific cut-off points. A subgroup analysis of upper gastrointestinal (UGI) tolerability was also performed. RESEARCH DESIGN AND METHODS: 1053 postmenopausal women with low BMD were randomized to alendronate 70 mg OW (N = 520) or risedronate 35 mg OW (N = 533). The percentage of patients who had measured BMD gains > or = 3%, and > or = 5% after 12 months at the hip trochanter, total hip, femoral neck, and lumbar spine (LS) was analyzed. The percentage of patients who experienced any bone loss, and those with measured losses of 3% or more at these sites after 12 months, was determined. The percentage of patients achieving reductions in urinary N-telopeptide of type 1 human collagen (NTX) > or = 40%, and serum C-telopeptide of type 1 collagen (CTx) > or = 60%, bone-specific phosphatase (BSAP) > or = 30%, and N terminal propeptide of type 1 procollagen (P1NP) > or = 50% at 3 months and 12 months was also determined. Tolerability, based on adverse experience reporting, was evaluated in a subgroup of patients with history of UGI disorders at baseline. RESULTS: A greater percentage of alendronate- than risedronate-treated patients had measured BMD gains (> or = 0%) (p < 0.05) at all sites at 12 months. Significantly more (p < 0.01) alendronate- than risedronate-treated patients had measured gains in BMD > or = 3% and > or = 5% at the hip trochanter, total hip, and LS spine. Significantly more (p < 0.05) risedronate- than alendronate-treated patients had an apparent loss of BMD (> 0% and > or = 3% loss) at the same sites. After 3 months, significantly (p < 0.001) more alendronate- than risedronate- treated patients achieved predefined reductions in all BCMs. Similar tolerability was demonstrated in both treatment groups, regardless of whether or not patients had a history of UGI disorders at baseline. CONCLUSIONS: Significantly more alendronate- than risedronate-treated patients achieved predefined increases in BMD at 12 months and reductions in BCMs at 3 months. Significantly more risedronate- than alendronate-treated patients were classified as apparent 'non-responders' (i.e. experienced any bone loss) after 12 months of therapy. The tolerability profiles of the two medications were similar.

Biochemical markers for prediction of 4-year response in bone mass during bisphosphonate treatment for prevention of postmenopausal osteoporosis.

Short-term changes in biochemical markers of bone turnover (bone markers) have been suggested as predictors of long-term response in bone mass during antiresorptive treatment. In the Danish cohort (n = 306) of the Early Postmenopausal Intervention Cohort (EPIC) Study (n = 1609) of oral alendronate (ALN) for prevention of postmenopausal osteoporosis, bone markers (urine C-telopeptides of type I collagen (uCTX), urine N-telopeptide cross-links of type I collagen (uNTX), serum total osteocalcin measured by ELISA [total OC (ELISA)], and serum total osteocalcin measured by RIA [total OC (RIA)]) were measured at 6-month intervals. The correlation between 6-month change in uCTX and 4-year change in spine and hip bone mineral density (BMD) was r = -0.41 and r = -0.42, respectively (P < 0.001). The corresponding values for the other bone markers were r = -0.53 and r = -0.42 (uNTX), r = -0.46 and r = -0.47 [total OC (ELISA)], and r = -0.43 and r = -0.41 [total OC (RIA)], all P < 0.001. ROC curves were used to analyse the ability of the bone markers to predict a change in spine BMD greater than 0%. The best performance [defined as the maximum value of (sensitivity plus specificity)] was found at the cut-off values of a -29% change from baseline in uCTX, a -45% change from baseline in uNTX, a -13% change from baseline in total OC (ELISA), and a -15% change from baseline in total OC (RIA). At these values the corresponding sensitivity was 66% (uCTX), 76% (uNTX), 70% [total OC (ELISA)], and 83% [total OC (RIA)]. The specificity was 80% (uCTX), 75% (uNTX), 71% [total OC (ELISA)], and 55% [total OC (RIA)]. The positive predictive value (PPV) was 82% (uCTX), 80% (uNTX), 77% [total OC (ELISA)], and 71% [total OC (RIA)]. The negative predictive value (NPV) was 64% (uCTX), 70% (uNTX), 64% [total OC (ELISA)], and 71% [total OC (RIA)]. In conclusion, the bone markers predicted a change in spine BMD greater than 0% with a high PPV and specificity. There was a trend toward better performance in this respect for the bone resorption markers.

Changes in bone density and turnover explain the reductions in incidence of nonvertebral fractures that occur during treatment with antiresorptive agents.

Some, but not all, antiresorptive agents have been shown to reduce the risk of nonvertebral fractures. Agents that significantly reduced nonvertebral fracture risk also appear to produce larger mean increases in bone mineral density (BMD) and reductions in biochemical markers (BCM) of bone turnover, compared with other agents. To examine the extent to which increases in BMD and reductions in BCM during antiresorptive therapy are associated with reductions in risk of nonvertebral fractures, we performed a meta-analysis of all randomized, placebo-controlled trials of antiresorptive agents conducted in postmenopausal women with osteoporosis (i.e. prior vertebral fracture or low BMD) with available relevant data. A total of 18 such trials with usable data were identified, including a total of 2,415 women with incident nonvertebral fractures over 69,369 women-years of follow-up. Poisson regression was used to estimate the association between changes in BMD or BCM during the first year and overall reductions in risk of nonvertebral fractures (vs. the placebo group) across all trials. Larger increases in BMD and larger reductions in BCM were significantly associated with greater reductions in nonvertebral fracture risk. For example, each 1% increase in spine BMD at 1 yr was associated with an 8% reduction in nonvertebral fracture risk (P = 0.02). Mean BMD changes at the hip were smaller than at the spine, but the predicted net effect on fracture risk was the same; an agent that increases spine BMD by 6% at 1 yr reduces nonvertebral fracture risk by about 39%, and an agent that increases hip BMD by 3% at 1 yr reduces nonvertebral fracture risk by about 46%. The results also predict that a 70% reduction in resorption BCM would reduce risk by 40%, and a 50% reduction in formation BCM would reduce risk by 44%. It appears that either BMD or BCM changes are able to explain the effect of treatment, because a separate variable for treatment was not independently significant in any models. These data demonstrate that larger increases in BMD at both the spine and hip and larger reductions in both formation and resorption BCM are associated with greater reductions in the risk of nonvertebral fractures. Antiresorptive agents that do not produce large increases in BMD or large reductions in BCM do not appear to and would not be expected to decrease the risk of nonvertebral fractures.