Impact of denosumab on the peripheral skeleton of postmenopausal women with osteoporosis: bone density, mass, and strength of the radius, and wrist fracture.

OBJECTIVE: The aim of this study was to report the effects of denosumab on radius cortical and trabecular bone density, mass, and strength, and wrist fracture incidence in the FREEDOM (Fracture REduction Evaluation of Denosumab in Osteoporosis every 6 Months) study. METHODS: In the FREEDOM study, postmenopausal women with osteoporosis (N = 7,808) received placebo or 60 mg of denosumab every 6 months for 36 months. Radius bone mineral density (BMD), bone mineral content, and strength (polar moment of inertia) were evaluated in two prespecified substudies using dual-energy x-ray absorptiometry (placebo, n = 209; denosumab, n = 232) or quantitative CT (placebo, n = 48; denosumab, n = 62). Prespecified analysis assessed wrist fracture incidence in all FREEDOM participants (placebo, N = 3,906; denosumab, N = 3,902), and post hoc subgroup analyses evaluated those with higher fracture risk (baseline femoral neck T-score ≤-2.5; placebo, N = 1,406; denosumab, N = 1,384). RESULTS: Denosumab significantly increased areal BMD (assessed by dual-energy x-ray absorptiometry) and volumetric BMD, bone mineral content, and polar moment of inertia (assessed by quantitative CT), compared with placebo, in radius cortical and trabecular bone at all time points evaluated (all P < 0.05). Wrist fracture incidence was 2.9% for placebo and 2.5% for denosumab (relative risk reduction, 16%; P = 0.21) on month 36. Participants with a femoral neck T-score of -2.5 or lower were at increased risk for wrist fracture, and denosumab significantly reduced wrist fracture incidence compared with placebo (placebo, 4.0%; denosumab, 2.4%; relative risk reduction, 40%; absolute risk reduction, 1.6%; P = 0.03). CONCLUSIONS: Denosumab significantly improves radius bone density, mass, and strength compared with placebo. In higher-risk women, denosumab significantly reduces wrist fracture risk.

Low bone mass prevalence, therapy type, and clinical risk factors in an HIV-infected Brazilian population.

Low bone mineral density (BMD) has been described in human immunodeficiency virus (HIV)-infected patients, but data on associated factors are still unclear, and to our knowledge, no reports are available in Brazil. Our goal was to evaluate BMD in HIV patients attending an outpatient clinic in Vitoria, Brazil. A sectional study was performed in 300 HIV-infected patients to measure BMD by dual-energy X-ray absorptiometry (DXA). Age, gender, anthropometric parameters, nadir and current CD4 cell count, HIV viral load, smoking habit, and current antiretroviral therapy (ART) associations were investigated by multivariable analysis. Based on World Health Organization T-score ranges, low BMD (T-score <-1.0 standard deviation [SD] in postmenopausal women and men aged 50 and older or Z-score <- 2.0 SD in premenopausal women and men below the age of 50) was detected in 54.7% (95% confidence interval: 49.1-60.3%) of the 300 enrolled patients. The observed median age was 46 yr (interquartile range: 39-52), 58% were male, 88.5% were on ART, and 21.4% smoked. The following factors were identified, by multiple logistic modeling, as being independently associated with low BMD: (1) male gender (4.6 [1.28-16.39]), (2) body mass index lower than 25 kg/m(2) (2.9 [1.31-6.49]), (3) menopause (13.4 [2.53-71.12]), and (4) HIV-1 undetectable viral load (7.9 [1.96-32.25]). Conversely, zidovudine (0.2 [0.04-0.85]) and nevirapine (0.1 [0.02-0.38]) use were inversely associated with low BMD. Low BMD was frequently found in our cohort of about 300 Brazilian HIV-infected subjects. This study supports the need for periodic DXA testing in HIV outpatient clinics.

Effects of intravenous ibandronate injection on renal function in women with postmenopausal osteoporosis at high risk for renal disease--the DIVINE study.

The Designed for intravenous (IV) Ibandronate reNal safety Evaluation (DIVINE) study was a 1-year prospective, randomized, open label, multi-center study that evaluated the renal safety of quarterly (every 3 months) ibandronate IV injection given over 15-30s compared with infusion given over 15 min, and weekly oral alendronate, in women with postmenopausal osteoporosis (PMO) at increased risk for renal disease. Both injection and infusion of IV ibandronate showed comparable safety to alendronate, with only small changes in serum creatinine (sCr) for each treatment group, and AEs were generally comparable between groups. All three treatments had similar effects on renal function, measured by change in baseline of the glomerular filtration rate; the ibandronate IV injection group was noninferior to the ibandronate IV infusion and weekly oral alendronate groups at 9 months, with similar results at 1 year. The results of this study demonstrate the profile of IV ibandronate, which allows it to be dosed as an IV injection in the primary care setting without the need for an infusion, even in patients with pre-existing hypertension or diabetes mellitus.

Official Positions for FRAX® clinical regarding international differences from Joint Official Positions Development Conference of the International Society for Clinical Densitometry and International Osteoporosis Foundation on FRAX®.

Osteoporosis is a serious worldwide epidemic. Increased risk of fractures is the hallmark of the disease and is associated with increased morbidity, mortality and economic burden. FRAX® is a web-based tool developed by the Sheffield WHO Collaborating Center team, that integrates clinical risk factors, femoral neck BMD, country specific mortality and fracture data and calculates the 10 year fracture probability in order to help health care professionals identify patients who need treatment. However, only 31 countries have a FRAX® calculator at the time paper was accepted for publication. In the absence of a FRAX® model for a particular country, it has been suggested to use a surrogate country for which the epidemiology of osteoporosis most closely approximates the index country. More specific recommendations for clinicians in these countries are not available. In North America, concerns have also been raised regarding the assumptions used to construct the US ethnic specific FRAX® calculators with respect to the correction factors applied to derive fracture probabilities in Blacks, Asians and Hispanics in comparison to Whites. In addition, questions were raised about calculating fracture risk in other ethnic groups e.g., Native Americans and First Canadians. In order to provide additional guidance to clinicians, a FRAX® International Task Force was formed to address specific questions raised by physicians in countries without FRAX® calculators and seeking to integrate FRAX® into their clinical practice. The main questions that the task force tried to answer were the following: The Task Force members conducted appropriate literature reviews and developed preliminary statements that were discussed and graded by a panel of experts at the ISCD-IOF joint conference. The statements approved by the panel of experts are discussed in the current paper.

Efficacy and tolerability of once-monthly oral ibandronate (150 mg) and once-weekly oral alendronate (70 mg): additional results from the Monthly Oral Therapy With Ibandronate For Osteoporosis Intervention (MOTION) study.

BACKGROUND: The MOTION (Monthly Oral Therapy with Ibandronate for Osteoporosis Intervention) study reported that once-monthly ibandronate was noninferior to once-weekly alendronate in terms of increasing bone mineral density (BMD) at the lumbar spine and total hip over 12 months. On analysis of secondary and exploratory end points in MOTION, which included trochanter and femoral neck BMD, monthly ibandronate was found to be noninferior to weekly alendronate. The coprimary, secondary, and exploratory BMD end points from MOTION have been previously reported. OBJECTIVE: This report presents additional results from the MOTION study, including response rates in terms of lumbar spine and total hip BMD gains above baseline; findings from a comparison of serum concentrations of bone turnover markers; and tolerability analysis, including adverse events that led to withdrawal and gastrointestinal (GI) adverse events. METHODS: MOTION was a 12-month (with 15-day follow-up), randomized, multinational, multicenter, double-blind, double-dummy, parallel-group, noninferiority study in postmenopausal women aged 55 to <85 years with osteoporosis. Patients were randomly assigned to receive 150-mg-monthly oral ibandronate and weekly alendronate-matched placebo, or 70-mg-weekly oral alendronate and monthly ibandronate-matched placebo, for 12 months. At baseline, day 7 of treatment, 3 and 6 months, 6 months + 7 days, and 12 months, serum concentrations of markers of bone resorption (C-telopeptide of the a chain of type 1 collagen [sCTX]) and bone formation (serum N-terminal propeptides of type 1 collagen) were measured in a subset of the total trial population. At baseline and month 12, BMD was measured using dual-energy x-ray absorptiometry. Exploratory analyses of patients whose spine, total hip, and trochanter BMD at 12 months were above baseline (responders) were also performed. RESULTS: A total of 1760 women were enrolled (ibandronate, 887 patients; alendronate, 873). The median changes in the trough concentrations of sCTX were -75.5% with monthly ibandronate and -81.2% with weekly alendronate. The percentage of patients with mean lumbar spine and total hip BMD gains above baseline (responders) were 90% and 87%, respectively, for ibandronate and 92% and 90%, respectively, for alendronate. GI adverse events were reported in

Is it ethical to use placebos in osteoporosis trials?

The use of placebo control groups (e.g., subjects using calcium and vitamin D) in osteoporosis trials with subjects at high risk for fracture has been systematically questioned by institutional review boards (IRBs). Regulatory agencies, on the other hand, continue to not only recommend but also require that placebo-controlled trials be presented for the registration of new drugs for osteoporosis treatment. The Declaration of Helsinki and its updates have upheld the principle that protection of research subjects' rights is of primary concern. Nevertheless, even the Declaration keeps clearly opening the possibility of using placebo-control designs if it is justified for "compelling and scientifically sound methodological reasons." The use of intermediary endpoints or surrogates to establish the efficacy or safety of new medications in the management of osteoporosis is currently considered scientifically insufficient. This concept has led regulatory agencies, such as the Food and Drug Administration in the United States and the European Medicines Agency in the European Union, to require "fragility fracture reduction" as the primary endpoint in clinical trials for the registration of new drugs. Superiority or noninferiority trials are alternatives to placebo-controlled designs. However, factors such as sample size, cost, and statistical limitations render these models impractical for the registration of new medications for osteoporosis. We recommend collaboration among regulatory agencies, IRBs, scientists, and ethicists on the design of clinical trials for the registration of new medications for reduction of fracture risk. Delay in developing mutually acceptable models may impair scientific development in the field and possibly deprive patients of potentially beneficial treatments.