Treatment Sequence for Osteoporosis.

BACKGROUND: Osteoporosis is a chronic progressive disease that requires lifelong monitoring and treatment. Sequencing from one treatment to another at different ages and stages of disease is an approach that can maximize benefits and avoid potential risks from long-term treatment with a single agent. OBJECTIVE: This article reviews clinical trial data in postmenopausal women that evaluate the effects of antiresorptive agents followed by other antiresorptives, osteoanabolic agents followed by antiresorptives, and antiresorptives followed by osteoanabolic medications. METHODS: Literature review and discussion. RESULTS: When medications are discontinued, in the absence of sequential therapy, bone turnover rates return to baseline or above baseline, and bone loss occurs. The rate of bone loss differs for different treatments, with a very slow decline after stopping bisphosphonates and a particularly rapid decline after stopping denosumab. Careful attention to osteoporosis medication transitions can mitigate bone density loss and its consequences. For women who remain at high risk, switching from bisphosphonates to the more potent antiresorptive, denosumab, will result in further improvement in bone mineral density (BMD). When indicated, stopping denosumab can be accomplished safely by transition to an adequate bisphosphonate regimen. For high- and very-high-risk patients, treating with osteoanabolic agents first, followed by antiresorptive agents, produces substantially larger BMD gains than the reverse treatment sequence, with the biggest differences seen for BMD of the hip. CONCLUSION: Awareness of the importance of treatment sequences can help improve osteoporosis care across the postmenopausal lifespan.

Romosozumab Efficacy in Postmenopausal Women With No Prior Fracture Who Fulfill Criteria for Very High Fracture Risk.

OBJECTIVE: We evaluated the efficacy of romosozumab in women from FRAME who had no prior fracture but met other criteria for very high fracture risk (VHFR). METHODS: In FRAME, postmenopausal women received romosozumab or placebo for 12 months (year 1) followed by denosumab for 12 months (year 2). In this post hoc analysis, we applied the following criteria from the American Association of Clinical Endocrinology to define VHFR: lumbar spine or total hip T-score <-3.0 and/or Fracture Risk Assessment Tool probability of major osteoporotic fracture >30% or hip fracture >4.5% to women with no fracture history at baseline (no fracture-VHFR [NF-VHFR]). Incidence of new vertebral, clinical, and nonvertebral fractures and mean bone mineral density (BMD) percentage change from baseline were assessed at years 1 and 2. RESULTS: Of the 7180 women in FRAME, 2825 were included in the NF-VHFR subgroup analysis. At year 1, romosozumab versus placebo reduced the incidence of new vertebral fracture (relative risk reduction [RRR]: 76%), clinical fracture (RRR: 60%), and nonvertebral fracture (RRR: 54%) (all P <.05). This fracture reduction was maintained through year 2 in women receiving the romosozumab-to-denosumab sequence versus the placebo-to-denosumab sequence for new vertebral, clinical, and nonvertebral fractures (RRR: 77%, 54%, and 46%, respectively; all P <.05). The mean BMD changes in both treatment groups were similar to those in the overall FRAME population at years 1 and 2. CONCLUSION: Romosozumab significantly reduced vertebral, clinical, and nonvertebral fracture risk and increased the BMD more than placebo in women at VHFR.

Romosozumab and antiresorptive treatment: the importance of treatment sequence.

To evaluate whether treatment sequence affects romosozumab response, this analysis reviewed studies where romosozumab was administered before or following an antiresorptive (alendronate or denosumab). Initial treatment with romosozumab followed by an antiresorptive resulted in larger increases in bone mineral density of both hip and spine compared with the reverse sequence. INTRODUCTION: Teriparatide followed by an antiresorptive increases bone mineral density (BMD) more than using an antiresorptive first. To evaluate whether treatment sequence affects romosozumab response, we reviewed randomized clinical trials where romosozumab was administered before (ARCH, FRAME) or following (STRUCTURE, Phase 2 extension) an antiresorptive (alendronate or denosumab, respectively). METHODS: We evaluated BMD percentage change for total hip (TH) and lumbar spine (LS) and response rates (BMD gains ≥ 3% and ≥ 6%) at years 1 and 2 (except STRUCTURE with only 1-year data available). RESULTS: With 1-year romosozumab initial therapy in ARCH and FRAME, TH BMD increased 6.2% and 6.0%, and LS BMD increased 13.7% and 13.1%, respectively. When romosozumab was administered for 1 year after alendronate (STRUCTURE) or denosumab (Phase 2 extension), TH BMD increased 2.9% and 0.9%, respectively, and LS BMD increased 9.8% and 5.3%, respectively. Over 2 years, TH and LS BMD increased 7.1% and 15.2% with romosozumab/alendronate, 8.5% and 16.6% with romosozumab/denosumab, and 3.8% and 11.5% with denosumab/romosozumab, respectively. A greater proportion of patients achieved BMD gains ≥ 6% when romosozumab was used first, particularly for TH, versus the reverse sequence (69% after romosozumab/denosumab; 15% after denosumab/romosozumab). CONCLUSION: In this study, larger mean BMD increases and greater BMD responder rates were achieved when romosozumab was used before, versus after, an antiresorptive agent. Since BMD on treatment is a strong surrogate for bone strength and fracture risk, this analysis supports the thesis that initial treatment with romosozumab followed by an antiresorptive will result in greater efficacy versus the reverse sequence.

Anabolic Agents for Postmenopausal Osteoporosis: How Do You Choose?

PURPOSE OF REVIEW: There are now three anabolic agents available for the treatment of postmenopausal women at high risk for fracture. The purpose of this review is to supply a rationale to aid in determining which agent should be used in which clinical settings. RECENT FINDINGS: Studies over the last decade have shown that anabolic agents produce faster and larger effects against fracture than antiresorptive agents. Furthermore, trials evaluating anabolic antiresorptive treatment sequences have shown that anabolic first treatment strategies produce the greatest benefits to bone density, particularly in the hip region. However, there are no head-to-head evaluations of the three anabolic therapies with fracture outcomes or bone density, and these studies are not likely to occur. How to decide which agent to use at which time in a woman's life is unknown. We review the most significant clinical trials of anabolic agents which have assessed fracture, areal or volumetric bone density, microarchitecture, and/or bone strength, as well as information gleaned from histomorphometry studies to provide a rationale for consideration of one agent vs another in various clinical settings. There is no definitive answer to this question; all three agents increase bone strength and reduce fracture risk rapidly. Since the postmenopausal lifespan could be as long as 40-50 years, it is likely that very high-risk women will utilize different anabolic agents at different points in their lives.

Anabolic Therapy and Optimal Treatment Sequences for Patients With Osteoporosis at High Risk for Fracture.

OBJECTIVE: Provide an update regarding anabolic medications for osteoporosis, which are often considered to be the last resort for patients with osteoporosis, after multiple fractures have already occurred and other medications have already been administered. METHODS: Literature review and discussion. RESULTS: Recent pivotal trial data for anabolic agents and randomized trials comparing anabolic and antiresorptive medications suggest that three anabolic agents (teriparatide, abaloparatide, and romosozumab) reduce nonvertebral and vertebral fractures faster and to a greater extent than potent antiresorptive treatments. Furthermore, bone density accrual is maximized when patients are given anabolic agents first, followed by potent antiresorptive therapy. Since total hip bone density during or after osteoporosis treatment has emerged as an excellent surrogate for future fracture risk, attaining a greater hip bone mineral density is a treatment goal for high-risk osteoporosis patients. CONCLUSION: This review defines the highest-risk patients and summarizes the rationale for the evolving role of anabolic therapy in the management of postmenopausal women at high risk for fracture. ABBREVIATIONS: ACTIVE = Abaloparatide Comparator Trial in Vertebral Endpoints; ARCH = Active Controlled Fracture Study in Postmenopausal Women with Osteoporosis at High Risk; BMD = bone mineral density; FRAME = Fracture Study in Postmenopausal Women with Osteoporosis; FRAX = Fracture Risk Assessment Tool; PTH = parathyroid hormone; TBS = trabecular bone score.

The evolving role of anabolic therapy in the treatment of osteoporosis.

PURPOSE OF REVIEW: Many physicians have long considered anabolic osteoporosis medication to be the last resort for patients after multiple fractures have already occurred. Thinking is evolving toward the view that anabolic agents should be used more proactively earlier in patients who are at high risk for fracture. RECENT FINDINGS: Recent data suggest that the three anabolic agents, teriparatide, abaloparatide and romosozumab, reduce nonvertebral and vertebral fractures faster and to a greater extent than the best antiresorptive treatments. SUMMARY: This review will summarize the evolving role of anabolic therapy in the management of the postmenopausal woman at high risk for fracture. Pivotal clinical trial data for the three anabolic agents are overviewed and studies comparing anabolic and antiresorptive medications are described. Studies comparing treatment sequences with anabolic and antiresorptive treatments are also summarized. High-risk patients who should be considered for initial treatment with anabolic medication are defined.

Romosozumab Treatment in Postmenopausal Women with Osteoporosis.

BACKGROUND: Romosozumab, a monoclonal antibody that binds sclerostin, increases bone formation and decreases bone resorption. METHODS: We enrolled 7180 postmenopausal women who had a T score of -2.5 to -3.5 at the total hip or femoral neck. Patients were randomly assigned to receive subcutaneous injections of romosozumab (at a dose of 210 mg) or placebo monthly for 12 months; thereafter, patients in each group received denosumab for 12 months, at a dose of 60 mg, administered subcutaneously every 6 months. The coprimary end points were the cumulative incidences of new vertebral fractures at 12 months and 24 months. Secondary end points included clinical (a composite of nonvertebral and symptomatic vertebral) and nonvertebral fractures. RESULTS: At 12 months, new vertebral fractures had occurred in 16 of 3321 patients (0.5%) in the romosozumab group, as compared with 59 of 3322 (1.8%) in the placebo group (representing a 73% lower risk with romosozumab; P<0.001). Clinical fractures had occurred in 58 of 3589 patients (1.6%) in the romosozumab group, as compared with 90 of 3591 (2.5%) in the placebo group (a 36% lower risk with romosozumab; P=0.008). Nonvertebral fractures had occurred in 56 of 3589 patients (1.6%) in the romosozumab group and in 75 of 3591 (2.1%) in the placebo group (P=0.10). At 24 months, the rates of vertebral fractures were significantly lower in the romosozumab group than in the placebo group after each group made the transition to denosumab (0.6% [21 of 3325 patients] in the romosozumab group vs. 2.5% [84 of 3327] in the placebo group, a 75% lower risk with romosozumab; P<0.001). Adverse events, including instances of hyperostosis, cardiovascular events, osteoarthritis, and cancer, appeared to be balanced between the groups. One atypical femoral fracture and two cases of osteonecrosis of the jaw were observed in the romosozumab group. CONCLUSIONS: In postmenopausal women with osteoporosis, romosozumab was associated with a lower risk of vertebral fracture than placebo at 12 months and, after the transition to denosumab, at 24 months. The lower risk of clinical fracture that was seen with romosozumab was evident at 1 year. (Funded by Amgen and UCB Pharma; FRAME ClinicalTrials.gov number, NCT01575834 .).

Long-term treatment strategies for postmenopausal osteoporosis.

PURPOSE OF REVIEW: Osteoporosis guidelines do not usually provide specific recommendations regarding what medication is most appropriate for individual patients. Generic oral bisphosphonates are often considered first-line treatment for osteoporosis, but treatment duration is limited, based on potential long-term safety concerns, and there is no consensus about what to do after 5 years. There are no recommendations concerning long-term management of osteoporosis over 30 or more years of postmenopausal life. RECENT FINDINGS: This review attempts to specify medication choices and provide the best clinical management strategies for women at different stages of life and with different underlying disease severity. Because there is no evidence that considers the entire postmenopausal lifespan, much of the discussion here will be based on expert opinion. The review considers a role for estrogens and selective estrogen receptor modulators, oral and intravenous bisphosphonates, denosumab and the anabolic agents, teriparatide and abaloparatide. SUMMARY: Optimal sequential monotherapy, over an average of 30 postmenopausal years, should be able to minimize exposure to pharmacology while maximizing benefits on bone strength and minimizing imminent and long-term risk of fracture.

Results of a fracture liaison service on hip fracture patients in an open healthcare system.

We assessed osteoporosis management in patients admitted for rehabilitation of acute hip fracture to an open system community hospital before and after institution of a fracture liaison service (FLS). Pre-FLS, we surveyed 60 patients 4-6 months after hip fracture. Subsequently, the FLS program performed routine consultations, and recommended lab, bone density testing (BMD) and osteoporosis medication. FLS program outcomes were assessed by survey in 75 patients after hip fracture. In the pre-FLS population, after hip fracture, 55 % changed calcium intake, 48 % changed vitamin D intake, and 35 % obtained a BMD. Osteoporosis medication was taken by 38 % before and 33 % after hip fracture. Post-FLS, 56 % changed calcium intake, 68 % changed vitamin D intake and 65 % obtained a BMD. Post-FLS, osteoporosis medication was taken by 21 % of patients before and 19 % after hip fracture. Our FLS program in hip fracture patients improved non-pharmacologic measures, but not the use of osteoporosis medication.

Effect of Abaloparatide vs Placebo on New Vertebral Fractures in Postmenopausal Women With Osteoporosis: A Randomized Clinical Trial.

IMPORTANCE: Additional therapies are needed for prevention of osteoporotic fractures. Abaloparatide is a selective activator of the parathyroid hormone type 1 receptor. OBJECTIVE: To determine the efficacy and safety of abaloparatide, 80 µg, vs placebo for prevention of new vertebral fracture in postmenopausal women at risk of osteoporotic fracture. DESIGN, SETTING, AND PARTICIPANTS: The Abaloparatide Comparator Trial In Vertebral Endpoints (ACTIVE) was a phase 3, double-blind, RCT (March 2011-October 2014) at 28 sites in 10 countries. Postmenopausal women with bone mineral density (BMD) T score ≤-2.5 and >-5.0 at the lumbar spine or femoral neck and radiological evidence ≥2 mild or ≥1 moderate lumbar or thoracic vertebral fracture or history of low-trauma nonvertebral fracture within the past 5 years were eligible. Postmenopausal women (>65 y) with fracture criteria and a T score ≤-2.0 and >-5.0 or without fracture criteria and a T score ≤-3.0 and >-5.0 could enroll. INTERVENTIONS: Blinded, daily subcutaneous injections of placebo (n = 821); abaloparatide, 80 µg (n = 824); or open-label teriparatide, 20 µg (n = 818) for 18 months. MAIN OUTCOMES AND MEASURES: Primary end point was percentage of participants with new vertebral fracture in the abaloparatide vs placebo groups. Sample size was set to detect a 4% difference (57% risk reduction) between treatment groups. Secondary end points included change in BMD at total hip, femoral neck, and lumbar spine in abaloparatide-treated vs placebo participants and time to first incident nonvertebral fracture. Hypercalcemia was a prespecified safety end point in abaloparatide-treated vs teriparatide participants. RESULTS: Among 2463 women (mean age, 69 years [range, 49-86]), 1901 completed the study. New morphometric vertebral fractures occurred less frequently in the active treatment groups vs placebo. The Kaplan-Meier estimated event rate for nonvertebral fracture was lower with abaloparatide vs placebo. BMD increases were greater with abaloparatide than placebo (all P < .001). Incidence of hypercalcemia was lower with abaloparatide (3.4%) vs teriparatide (6.4%) (risk difference [RD], −2.96 [95%CI, −5.12 to −0.87]; P = .006). [table: see text]. CONCLUSIONS AND RELEVANCE: Among postmenopausal women with osteoporosis, the use of subcutaneous abaloparatide, compared with placebo, reduced the risk of new vertebral and nonvertebral fractures over 18 months. Further research is needed to understand the clinical importance of RD, the risks and benefits of abaloparatide treatment, and the efficacy of abaloparatide vs other osteoporosis treatments. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01343004.

Anabolic and antiresorptive therapy for osteoporosis: combination and sequential approaches.

In the recent Bone Key Reports review, it was noted that combinations of anabolic and antiresorptive agents have potential to improve bone density and bone strength more than either agent as monotherapy. Small clinical trials have been performed evaluating combinations of PTH1-34 (TPTD) or PTH1-84 (PTH) with a variety of antiresorptives including hormone/estrogen therapy, raloxifene, alendronate, risedronate, ibandronate, zoledronic acid, and denosumab. Most of the studies evaluate dual-energy X-ray absorptiometry outcomes, and a few trials report volumetric mineral density (BMD) by quantitative computed tomography, followed by finite element modeling to calculate bone strength. None of the studies has been powered to assess differences in fracture incidence between combination therapy and monotherapy. BMD outcomes vary based on the timing of introduction of the anabolic agent (before, during, or after antiresorptive treatment), as well as the specific anabolic and antiresorptive used. Furthermore, effects of combination therapies are site-dependent. The most consistent effect of combining antiresorptive agents with PTH or TPTD is a superior hip BMD outcome compared with TPTD/PTH alone. This is most evident when TPTD/PTH is combined with a bisphosphonate or denosumab. In contrast to findings in the hip, in the majority of studies, there is no benefit to spine BMD with combination therapy vs monotherapy. The 2 exceptions to this are when TPTD is combined with denosumab and when TPTD is given as monotherapy first for 9 months, followed by the addition of alendronate (with continuation administration of TPTD). Based on what we now know, in patients previously treated with bisphosphonates who suffer hip fractures or who have very low or declining hip BMD, strong consideration should be given to starting TPTD and continuing a potent antiresorptive agent (possibly switching to zoledronic acid or denosumab) to improve hip BMD and strength quickly. Furthermore, in treatment naïve individuals with very severe osteoporosis, such as those with spine and hip fractures, combination therapy with TPTD and denosumab or TPTD followed by combination treatment with a potent bisphosphonate or denosumab should be considered to maximize early increases in BMD throughout the skeleton (Cosman BoneKEy Rep 3, 2014).

Oral daily PTH(1-34) tablets (EB613) in postmenopausal women with low BMD or osteoporosis: a randomized, placebo-controlled, six-month, phase 2 study.

Anabolic treatment is indicated for high and very-high risk patients with osteoporosis, but acceptance is limited because current anabolic medications require subcutaneous injections. The purpose of this study was to assess the effects of a novel orally administered parathyroid hormone (PTH) tablet on serum markers of bone formation [N-terminal propeptide of Type I procollagen (PINP) and osteocalcin (OC)] and bone resorption [crosslinked C-telopeptide (CTX)], bone mineral density (BMD) and safety in postmenopausal women with low BMD or osteoporosis. In this 6-month, double-blind, placebo-controlled study, 161 patients were randomized to oral PTH tablets containing 0.5, 1.0, 1.5, or 2.5 mg or placebo daily. Biochemical markers were assessed at 1, 2, 3 and 6 months and BMD of lumbar spine, total hip and femoral neck was measured at 6 months. Biochemical marker changes were dose dependent with minimal or no effect at the two lowest doses. At the highest dose (2.5 mg once daily), serum PINP and OC levels increased 30% within 1 month after oral PTH initiation (p < 0.0001), remained elevated through 3 months and were back to baseline at 6 months. In contrast, serum CTX levels declined 16% and 21% below baseline at 3 and 6 months respectively (both p ≤ 0.02). At 6 months, 2.5 mg tablets increased mean BMD vs placebo of the lumbar spine by 2.7%, total hip by 1.8%, and femoral neck by 2.8% (all p ≤ 0.01). There were no drug-related serious adverse events. The most common adverse events were headache, nausea, and dizziness. In contrast to subcutaneous PTH, the oral PTH tablet appears to increase BMD rapidly by the dual mechanism of stimulating formation and inhibiting bone resorption. This might be the first effective oral anabolic alternative to subcutaneous administration for the treatment of low BMD or osteoporosis.

Despite the superior benefits of bone building (anabolic) agents and guidelines supporting their use, these medications are used in a minority of patients for whom they are appropriate, in part because they require daily or monthly injections, which limit patient acceptance. An oral anabolic tablet has potential to address this substantial treatment gap. In this double-blind, placebo controlled, dose-finding randomized study, 161 postmenopausal women with low bone mineral density or osteoporosis were treated with varying doses of the active part of parathyroid hormone [PTH(1-34)] or placebo given in daily oral tablets for 6 months. The highest oral PTH tablet dose (2.5 mg), produced an increase in markers of bone formation while simultaneously decreasing the markers of bone breakdown. Significant gains in bone mineral density of the spine and hip were observed at the end of the 6-month study and there were no significant safety concerns. The 2.5 mg oral PTH tablet dose was well tolerated when patients were instructed to titrate up to the full dose. We conclude that this PTH tablet might be the first effective orally administered bone building medication and should be studied further in treatment of women with osteoporosis.

Effect of Abaloparatide on Bone Microarchitecture Assessed by Trabecular Bone Score in Women With Osteoporosis: Post Hoc Analysis of ACTIVE and ACTIVExtend.

Although bone mineral density (BMD) is a predictor of fracture, many fractures occur in women with T-scores > -2.5. Bone microarchitecture, assessed by trabecular bone score (TBS), predicts fracture risk independent of BMD. We evaluated whether abaloparatide improves TBS and whether TBS trends were associated with vertebral fracture risk reduction. Women with osteoporosis randomized to abaloparatide or placebo for 18 months (ACTIVE), followed by alendronate for 24 months (ACTIVExtend), with evaluable TBS, were included in this post hoc analysis (N = 911). TBS was calculated from spine BMD scans using an algorithm adjusted for tissue thickness (TBSth ) at baseline, 6, 18, and 43 months. Mean increments in TBSth from baseline within and between treatment groups, proportion of women with TBSth increments above least significant change (LSC) and proportion with degraded TBSth (<1.027) were calculated. Risk estimates for vertebral fracture were compared using binary logistic regressions adjusted for baseline age and spine BMD. At baseline, 42% had degraded TBSth . Mean TBSth increased 4% after 18 months abaloparatide (p < 0.001) and was unchanged with placebo. After 2 subsequent years of alendronate, the total cumulative TBSth increase was 4.4% with abaloparatide/alendronate and 1.7% with placebo/alendronate (group difference, p < 0.001). At 43 months, the proportion of women with degraded TBSth had declined to 21% with abaloparatide/alendronate and 37% with placebo/alendronate (p < 0.05). An increase in TBSth  ≥ LSC was observed in 50% of abaloparatide-treated women at 18 months and was associated with decreased odds (odds ratio [OR]; 95% confidence interval [CI]) of vertebral fracture (0.19; 95% CI, 0.04-0.80, 6 months; 0.30; 95% CI, 0.11-0.79, 43 months). In conclusion, abaloparatide increased TBSth rapidly and progressively over 18 months and increments were maintained over 2 years with alendronate. TBSth increase was associated with vertebral fracture risk reduction. Microarchitectural improvement may be one mechanism by which abaloparatide strengthens vertebral bone. © 2023 Radius Health, Inc and The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Effects of four-year cyclic versus two-year daily teriparatide treatment on volumetric bone density and bone strength in postmenopausal women with osteoporosis.

PURPOSE: To evaluate the effects of cyclic vs daily teriparatide treatment (TPTD) on volumetric bone mineral density (vBMD) and bone strength at the hip and spine in women who were previously untreated. METHODS: A total of 86 women were randomized to a 24-month open label treatment of either daily TPTD (20 µg daily) or cyclic TPTD (20 µg daily for 3 months followed by 3 months off). During a 2-year extension, women in the daily TPTD group were switched to alendronate (ALN) and those in the cyclic TPTD group continued on cyclic TPTD (without any ALN). QCT images were acquired at baseline, 2-years (n = 54) and 4-years (n = 35) and analyzed for volumetric integral, cortical and trabecular bone mineral density (vBMD) and bone strength (by finite element analysis) at the hip and spine. The primary analysis presented here compared the responses across equal total TPTD doses (2 years daily vs 4 years cyclic). RESULTS: In the spine, integral vBMD and strength increased substantially after 2 years daily and 4 years cyclic TPTD, with no significant differences (vBMD +12 % vs +11 %, respectively, p = 0.70; spine strength +21 % vs +16 %, respectively, p = 0.35). At the hip, the gains were smaller, but again no significant differences were detected between the groups for the increases in either vBMD (+2 % in both groups, p = 0.97) or hip strength (3 % vs 3 %, p = 0.91). In the spine, the vBMD increment was about twice as large in the trabecular vs peripheral compartment; in the hip, significant vBMD gain was seen only in the trabecular compartment. CONCLUSIONS: The gains in volumetric BMD and bone strength for an equivalent dose of TPTD did not depend on whether it was administered every day over two years or cyclically over four years.

Responses of urinary N-telopeptide and renal calcium handling to PTH infusion after treatment with estrogen, raloxifene, and tamoxifen.

This prospective, randomized, placebo-controlled study investigated whether estrogen, tamoxifen, and raloxifene protect the skeleton from the acute catabolic effects of continuous PTH(1-34) infusion. It was infused over 24 h in 25 postmenopausal women both before and while on medication for 16-20 weeks (estrogen n = 7, raloxifene n = 5, tamoxifen n = 7, placebo n = 6). Blood and urine samples were collected at baseline and every 4 h during the PTH(1-34) infusion and analyzed for calcium homeostasis, bone remodeling, and specific cytokines. Data for the premedication PTH(1-34) infusions were pooled. During the premedication PTH(1-34) infusions, serum calcium and urine phosphorus increased, while serum phosphorus and urine calcium declined. Osteocalcin decreased (mean 18%), while urine NTX increased (mean 315%). Serum IL-6 increased 260%, but there were no other cytokine changes as a result of the PTH(1-34) infusion. On medication, the mean peak change in NTX with PTH(1-34) infusion was less (77, 59, and 31 nM/mM with raloxifene, tamoxifen, and estrogen, respectively). The reduction in urine calcium excretion was prolonged with each agent but only significantly with estrogen. There was no reduction in the IL-6 elevation induced by PTH(1-34) with any medication. The differential skeletal resorption response to PTH(1-34) infusion after the treatments may reflect different potencies of these agents or variability in interaction with the estrogen receptor. Renal calcium conservation and the blunted response of bone resorption to PTH(1-34) infusion may be mechanisms by which estrogen and estrogen agonist/antagonist agents preserve bone mass.

Multiple Vertebral Fractures After Denosumab Discontinuation: FREEDOM and FREEDOM Extension Trials Additional Post Hoc Analyses.

It is uncertain whether the risk of vertebral fracture (VF) and multiple vertebral fractures (MVFs; ≥2 VFs) after denosumab (DMAb) discontinuation is related to treatment duration. A prior analysis of Fracture Reduction Evaluation of Denosumab in Osteoporosis Every 6 Months (FREEDOM) and FREEDOM Extension trials did not find a relationship with DMAb duration and may have underreported MVF incidence because it included women who did not have radiographs. In this post hoc exploratory analysis, the crude incidence and annualized rates of VF and MVF were determined in patients with ≥7 months' follow-up and ≥1 spine radiograph after discontinuing placebo or DMAb. A multivariate analysis was performed to identify predictors of MVF. Clinical characteristics of patients with ≥4 VFs were explored. This analysis included women who discontinued after placebo (n = 327) or DMAb either from FREEDOM or FREEDOM Extension (n = 425). The DMAb discontinuation group was subsequently dichotomized by treatment duration: short-term (≤3 years; n = 262) and long-term (>3 years; n = 213) treatment. For any VF, exposure-adjusted annualized rates per 100 patient-years (95% confidence interval [CI]) were 9.4 (95% CI, 6.4-13.4) for placebo, 6.7 (95% CI, 4.2-10.1) for short-term DMAb, and 10.7 (95% CI, 7.4-15) for long-term DMAb. Annualized rates for MVF were 3.6 (95% CI, 1.9-6.3), 2.9 (95% CI, 1.4-5.4), and 7.5 (95% CI, 4.8-11.1), respectively. Annualized rates for ≥4 VFs were 0.59 (95% CI, 0.1-2.1), 0.57 (95% CI, 0.1-2.1), and 3.34 (95% CI, 1.7-6.0), respectively. In a multivariate regression model, DMAb duration was significantly associated with MVF risk (odds ratio 3.0; 95% CI, 1.4-6.5). Of 15 patients with ≥4 VFs, 13 had DMAb exposure (mean ± standard deviation [SD], 4.9 ± 2.2 years). The risk of MVF after DMAb discontinuation increases with increased duration of DMAb treatment. Patients transitioning off DMAb after 3 years may warrant more frequent administration of zoledronic acid or another bisphosphonate to maintain bone turnover and bone mineral density (BMD) and prevent MVF. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Denosumab in the Treatment of Osteoporosis: 10 Years Later: A Narrative Review.

The fully human monoclonal antibody denosumab was approved for treatment of osteoporosis in 2010 on the basis of its potent antiresorptive activity, which produces clinically meaningful increases in bone mineral density (BMD) and reduces fracture risk at key skeletal sites. At that time, questions remained regarding the long-term safety and efficacy of this receptor activator of nuclear factor kappa-B ligand (RANKL) inhibitor; and with clinical experience, new questions have arisen regarding its optimal use. Here, we examine these questions through the lens of data from the FREEDOM trial program and other studies to determine where denosumab fits in the osteoporosis treatment landscape. Clinical consensus and evidentiary support have grown for denosumab as a highly effective anti-osteoporosis therapy for patients at high risk of fracture. In the 10-year FREEDOM Extension study, denosumab treatment produced progressive incremental increases in BMD, sustained low rates of vertebral fracture, and further reduction in nonvertebral fracture risk without increased risk of infection, cancer, or immunogenicity. There was no evidence that suppression of bone turnover or mineralization was excessive, and rates of osteonecrosis of the jaw (ONJ) and atypical femoral fracture (AFF) were very low. It is now recognized, however, that transitioning to another anti-osteoporosis therapy after denosumab discontinuation is essential to mitigate a transient rebound of bone turnover causing rapid BMD loss and increased risk of multiple vertebral fractures (MVFs). Taken together, the available data show that denosumab has a favorable benefit/risk profile and is a versatile agent for preventing osteoporotic fractures in the short and long term. Video abstract: Denosumab in the Treatment of Osteoporosis-10 Years Later (MP4 62727 KB).

Effects of teriparatide and loading modality on modeling-based and remodeling-based bone formation in the human femoral neck.

PURPOSE: We have previously shown that a brief course of teriparatide (TPTD) stimulates bone formation in the cancellous and endocortical envelopes of the human femoral neck, and the regions of tension and compression respond differently. The purpose of the present study was to determine how much of the new bone was formed by modeling-based formation (MBF) or remodeling-based formation (RBF). METHODS: We performed a double-blind trial of TPTD vs. placebo (PBO) in patients about to undergo a total hip replacement (THR) for osteoarthritis. Participants were randomized to receive daily TPTD 20 µg or PBO for an average of 6.1 weeks (range 4.1-11.8 weeks) prior to THR. After an average of 3 weeks of study drug, double tetracycline labels were administered per standard protocol. During the THR an intact sample of the mid-femoral neck (FN) was procured; this was fixed, embedded, and sectioned transversely. Histomorphometric analysis was performed in the cancellous, endocortical, and periosteal envelopes. Additionally, separate analyses were performed in the tensile and compressive regions of the endocortical and periosteal envelopes. Sites of new bone formation were identified by the presence of tetracycline labels and designated as MBF if the underlying cement line was smooth and as RBF if it was scalloped. New bone formation on smooth cement lines adjacent to scalloped reversal lines was designated as overflow RBF (oRBF). The referent for all indices was bone surface (BS). RESULTS: In the cancellous and endocortical envelopes, the proportion of mineralizing surface engaged in RBF and oRBF was higher in the TPTD-treated than the PBO-treated subjects. There was also a trend toward higher MBF in TPTD vs. PBO in both envelopes. In linear mixed-effects models, TPTD was predicted to increase formation differently on the tensile and compressive surfaces depending on patient-specific anatomy, including body weight, FN angle, offset, and cortical width and porosity. Eroded surface was not different between groups in either envelope and no significant differences were observed in any parameter in the periosteal envelope. CONCLUSION: We conclude that the predominant early effect of TPTD in the human femoral neck is to stimulate RBF and oRBF with a trend toward an increase in MBF in the endocortical and cancellous envelopes.

Romosozumab Followed by Antiresorptive Treatment Increases the Probability of Achieving Bone Mineral Density Treatment Goals.

Increases in bone mineral density (BMD) with osteoporosis treatment are associated with reduced fracture risk. Increasing BMD is therefore a goal of osteoporosis therapy. Here, we compare the probability of achieving a T-score of > -2.5 over 3 years at the total hip (TH) or lumbar spine (LS) in women with osteoporosis, ≥55 years of age, after the following treatment sequences: 1 year romosozumab followed by 2 years denosumab (FRAME and FRAME extension trials), 1 year romosozumab followed by 2 years alendronate, or alendronate-only for 3 years (ARCH trial). Probabilities of attaining the BMD target within 1 year of treatment were also determined. At both skeletal sites, in women with a baseline Tscore ≥ -2.7, there was >50% probability of achieving the BMD target with any 3-year regimen. The probability of achieving the target BMD in those with a baseline TH Tscore equal to -3.0 was 61% with romosozumab/denosumab, 38% with romosozumab/alendronate, and 9% with alendronate. In those with a baseline LS Tscore equal to -3.0, the probability of achieving a T-score > -2.5 was 93% with romosozumab/denosumab, 81% with romosozumab/alendronate, and 55% with alendronate. With 1 year of treatment, in patients with a baseline TH T-score equal to -2.7, the probability of reaching the target Tscore with romosozumab was 71% to 78% and 38% with alendronate. For patients with an initial LS T-score equal to -3.0, the probability of achieving the target T-score over 1 year was 85% to 86% with romosozumab and 25% for alendronate. Our findings suggest baseline BMD and the probability of achieving BMD T-score goals are factors to consider when selecting initial treatment for patients with osteoporosis. As baseline T-score falls below -2.7 (TH) and -3.0 (LS), alendronate has <50% likelihood of achieving a BMD goal above osteoporosis range, whereas these probabilities remain relatively high for regimens beginning with romosozumab. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.