Changes of Circulating MicroRNAs in Response to Treatment With Teriparatide or Denosumab in Postmenopausal Osteoporosis

CONTEXT

Expression of microRNAs (miRs) related to bone metabolism in the serum may be affected by antiosteoporotic treatment.

OBJECTIVE

To investigate the effect of two antiosteoporotic agents with opposite effects on bone metabolism on miR expression profile in the serum.

DESIGN

Observational, open label, nonrandomized clinical trial.

SETTING

The outpatient clinics for Metabolic Bone Diseases of 424 General Military Hospital, Thessaloniki, Greece.

PATIENTS AND INTERVENTIONS

Postmenopausal women with low bone mass were treated with either teriparatide (TPTD; n = 30) or denosumab (n = 30) for 12 months.

MAIN OUTCOME MEASURES

Changes in the serum expression of selected miRs linked to bone metabolism at 3 and 12 months of treatment. Secondary measurements: associations of measured miRs with changes in bone mineral density (BMD) at 12 months and the bone turnover markers (BTMs) C-terminal cross-linking telopeptide of type I collagen and procollagen type I N-terminal propeptide at 3 and 12 months.

RESULTS

We found significantly decreased relative expression of miR-33-3p at 3 months (P = 0.03) and of miR-133a at 12 months (P = 0.042) of TPTD treatment. BMD values at 12 months of TPTD treatment were significantly and inversely correlated with miR-124-3p expression at 3 months (P = 0.008). Relative expression of miR-24-3p and miR-27a was correlated with changes in BTMs during TPTD treatment and of miR-21-5p, miR-23a-3p, miR-26a-5p, miR-27a, miR-222-5p, and miR-335-5p with changes in BTMs during denosumab treatment.

CONCLUSIONS

Circulating miRs are differentially affected by treatment with TPTD and denosumab. TPTD affects the relative expression of miRs related to the expression of RUNX-2 (miR-33) and DKK-1 gene (miR-133).

Therapeutic benefits of neoadjuvant and post-operative denosumab on sacral giant cell tumor: a retrospective cohort study of 30 cases

PURPOSE

Denosumab, a new monoclonal antibody that inhibits receptor activator for nuclear factor Kβ ligand (RANKL), has recently been approved by FDA for the treatment of aggressive giant cell tumor of bone (GCTB). So we initiated this study to evaluate the clinical benifits of denosumab used preoperatively or postoperatively.

METHODS

Patients diagnosed with classic sacral GCT without metastasis were included in this study. Patients were assigned into 3 groups according to the use of denosumab: control group 1, post-operative group 2 and neoadjuvant group 3. The latter two groups were treated with 120 mg of subcutaneous denosumab every 4 weeks with loading doses on days 8 and 15 of the first cycle. The primary endpoints were event-free-survival (EFS) and objective response rate (OPR) based on RECIST criteria. A system (MUD system) proposed by our center was applied to score the sacral nerve deficit changes before surgery in group 3.

RESULTS

A total 30 patients (13 men and 17 women, mean age 34.7 years, range 15-56) were enrolled from April 2014 to July 2016. Group 1 included 10 patients, group 2 9 and group 3 11. The study ended in March 01, 2017, and followup ranged from 3 to 36 months (mean 18.3). Two patients with PET-CT showed SUV max uptake down to muscle tissue level. In the neoadjuvant group 3 7 patients had partial responses and 4 stable disease (ORR 63.6%; 95% CI 35-92). Most (80%) patients achieved significant improvement in pain and great relief in the bladder and bowel functions. In 4 patients the urocatheter was removed after neoadjuvant denosumab.

CONCLUSION

Neoadjuvant therapy with denosumab can significantly relieve the symptoms and neurologic deficits.

Rebound-associated vertebral fractures after discontinuation of denosumab for the treatment of maxillitis

We reported a 69-year-old female who discontinued denosumab due to dental treatment and subsequently suffered rebound-associated vertebral fractures 10 months after the last injection. This case raised an alarm regarding the discontinuation of denosumab for dental treatment. Denosumab, a human monoclonal antibody administered by subcutaneous injection, to the best of our knowledge, is the only fully investigated inhibitor of receptor activator of nuclear factor kappa B ligand. Discontinuation of denosumab leads to bone turnover rebound and rapid bone mineral density loss. Several studies have reported rebound-associated vertebral fractures after discontinuation of denosumab. We report on a new case of rebound-associated vertebral fractures after discontinuation of denosumab. A 69-year-old female, who withdrew from denosumab treatment after 3 years due to maxillitis, presented to our hospital with severe low back pain without any history of trauma. Ten months had passed since the last injection. Magnetic resonance imaging showed five acute vertebral fractures, which appeared to be rebound-associated vertebral fractures caused by discontinuation of denosumab due to dental treatment. This case clearly demonstrates the risk of discontinuation of denosumab for dental treatment.

Significant bone loss after stopping long-term denosumab treatment: a post FREEDOM study

We evaluate 38 elderly women who had received long-term denosumab treatment after stopping the drug. Taking into account the gain during treatment and the loss after stopping treatment, they lost 35.5% of the total gain in the spine, 44.6% of the total gain in the femoral neck, and 103.3% in the total hip.

INTRODUCTION

Denosumab (DMAb) is a soluble inhibitor of the receptor activator of nuclear factor-kappaB ligand (RANKL) and, therefore, does not incorporate into the bone matrix. Consistently, DMAb discontinuation is associated with reversal of the effects attained with treatment.

PURPOSE

The aim of this study is to assess changes in BMD after a year of discontinuation of DMAb in a group of postmenopausal women treated with DMAb for 7 or 10 years. Secondly, is to evaluate the occurrence of fragility fractures.

METHODS

Women who had participated in the FREEDOM study and its extension were invited to participate in this follow-up study. BMD at LS and hip and spine X-rays were obtained. Results were compared to the last value obtained while in treatment to assess changes after discontinuation.

RESULTS

Thirty-eight women, mean age: 81 ± 3.4 years completed study procedures; none had received bisphosphonates after stopping DMAb. Mean gap time between DMAb last dose and the follow-up visit was 17 months (range 16-20 months). Bone mineral density (BMD) decreased significantly in all regions: - 8.1% in LS, - 6% in FN, and - 8.4% in TH. Five (5/38, 13.15%) patients had a fragility fracture, one suffered a wrist fracture, and four experienced vertebral fractures. Three patients suffered one vertebral fracture and one of them had two vertebral fractures. Laboratory results showed the following mean values: CTX = 996 ± 307 pg/ml (normal values 550 ± 226 pg/ml); osteocalcin = 55.2 ± 18.6 ng/ml (normal value 42 ng/ml); and 25 OH vitamin D = 23.7 ± 6.9 ng/ml.

CONCLUSION

Our results describe the rapid bone loss occurring after cessation of denosumab treatment. Further studies are needed to assess if patients have a higher risk of fracture after stopping DMAb and if so, which patients have the highest risk, and assess the role of transitioning to bisphosphonates in the long term.

Cost-Effectiveness Analysis of Monthly Zoledronic Acid, Zoledronic Acid Every 3 Months, and Monthly Denosumab in Women With Breast Cancer and Skeletal Metastases: CALGB 70604 (Alliance)

Purpose Skeletal-related events (SREs) such as pathologic fracture, spinal cord compression, or the necessity for radiation or surgery to bone metastasis cause considerable morbidity, decrements in quality of life, and costs to the health care system. The results of a recent large randomized trial (Cancer and Leukemia Group B/Alliance for Clinical Trials in Oncology [CALGB/Alliance 70604]) showed that zoledronic acid (ZA) every 3 months was noninferior to monthly ZA in reducing the risks of SREs. We sought to determine the cost-effectiveness (CE) of monthly ZA, ZA every 3 months, and monthly denosumab in women with breast cancer and skeletal metastases. Methods Using a Markov model, costs per SRE avoided were calculated for the three treatments. Sensitivity analyses were performed where denosumab SRE probabilities were assumed to be 50%, 75%, and 90% lower than the ZA SRE probabilities. Quality-adjusted life-years were also calculated. The analysis was from the US payer perspective. Results The mean costs of the denosumab treatment strategy are nine-fold higher than generic ZA every 3 months. Quality-adjusted life-years were virtually identical in all the three treatment arms; hence, the optimal treatment would be ZA every 3 months because it was the least costly treatment. The sensitivity analyses showed that relative to ZA every 3 months, the incremental costs per mean SRE avoided for denosumab ranged from $162,918 to $347,655. Conclusion ZA every 3 months was more CE in reducing the risks of SRE than monthly denosumab. This analysis was one of the first to incorporate the costs of generic ZA and one of the first independent CE analyses not sponsored by either Novartis or Amgen, the makers of ZA and denosumab, respectively. ZA every 3 months is the more CE option and more reasonable alternative to monthly denosumab.

One and two-year persistence with different anti-osteoporosis medications: a retrospective cohort study

Adherence to anti-osteoporosis medications is poor. We carried out a cohort study using a real-world population database to estimate the persistence of anti-osteoporosis drugs. Unadjusted 2-year persistence ranged from 10.3 to 45.4%. Denosumab users had a 40% lower risk of discontinuation at 2 years compared to alendronate users.

PURPOSE

The purpose of this study was to estimate real-world persistence amongst incident users of anti-osteoporosis medications.

METHODS

This is a retrospective cohort using data from anonymised records and dispensation data ( www.sidiap.org ). Eligibility comprised the following: women aged ≥50, incident users of anti-osteoporosis medication (2012), with data available for at least 12 months prior to therapy initiation. Exclusions are other bone diseases/treatments and uncommon anti-osteoporosis drugs (N < 100). Follow-up was from first pharmacy dispensation until cessation, end of study, censoring or switching. Outcomes are 2- and 1-year persistence with a permissible gap of up to 90 days. Persistence with alendronate was compared to other bisphosphonates, strontium ranelate, selective oestrogen receptor modulators, teriparatide and denosumab. Cox models were used to estimate hazard ratios of therapy cessation according to drug used after adjustment for age, sex, BMI, smoking, alcohol drinking, Charlson co-morbidity index, previous fractures, use of anti-osteoporosis medication/s, oral corticosteroids and socio-economic status.

RESULTS

A total of 19,253 women were included. Unadjusted 2-year persistence [95% CI] ranged from 10.3% [9.1-11.6%] (strontium ranelate) to 45.4% [43.1-47.8%] (denosumab). One-year persistence went from 35.8% [33.9%-37.7%] (strontium ranelate) to 65.8% [63.6%-68.0%] (denosumab). At the end of the first year and compared to alendronate users, both teriparatide and denosumab users had reduced cessation risk (adjusted HR 0.76, 95% CI 0.67-0.86 and 0.54, 95% CI 0.50-0.59 respectively) while at the end of the second year, only denosumab had a lower risk of discontinuation (adjusted HR 0.60, 95% CI 0.56-0.64).

CONCLUSIONS

Unadjusted 2-year persistence is suboptimal. However, both teriparatide and denosumab users had better 1-year persistence and only denosumab had 2-year better persistence compared to alendronate users. Unmeasured confounding by indication might partially explain our findings.

Denosumab-Associated Severe Hypocalcemia in a Patient With Chronic Kidney Disease

Denosumab is a monoclonal antibody directed against the receptor activator of nuclear factor kappa B ligand (RANKL). Denosumab has been shown to reduce the risk of skeletal-related events, including spinal cord compression, pathologic fracture and hypercalcemia of malignancy in patients with bone metastases. Hypocalcemia is a known side effect of denosumab, occurring in an estimated 8-14% of the patients. Here, we present an asymptomatic patient with stage-5 chronic kidney disease and severe hypocalcemia who had received denosumab 1 month earlier.

Retrospective evaluation of serum CTX levels after denosumab discontinuation in patients with or without prior exposure to bisphosphonates

Discontinuation of denosumab (Dmab) therapy is associated with lower serum CTX levels in osteoporotic patients previously exposed to bisphosphonates compared to those who were not.

INTRODUCTION

Discontinuation of Dmab therapy is followed by a transient increase of bone turnover markers (BTMs) above pretreatment values, together with accelerated bone loss, and potentially an increased risk of multiple vertebral fractures. Since a substantial proportion of patients discontinuing Dmab have previously been exposed to bisphosphonates (BPs), we hypothesized that previous BP therapy could attenuate this increase in bone turnover because of the prolonged biological effects of BPs on bone.

METHODS

In a retrospective observation, we assessed serum CTX levels between 7 and 24 months after the last Dmab injection in 37 patients (33 women and 4 men, aged 50 to 84 years). CTX levels were analyzed according to the number of Dmab injections (1 or multiple) and previous exposure to BPs.

RESULTS

In 8 patients who had received only 1 Dmab injection, 7 out of 8 were previously on BPs and none of them showed CTX values above the premenopausal range after Dmab discontinuation. CTX also remained in the premenopausal range in 14 out of 17 patients who discontinued Dmab after multiple (4.1 ± 1.4, range 2-7) injections but were previously exposed to BPs (mean exposure 6.9 ± 5.8 years, range 11 months-15 years; mean time interval between BP exposure and Dmab initiation 25 ± 10 months, range 0-48). In contrast, in 12 patients who discontinued Dmab after multiple (5, range 3-9) injections without prior exposure to BPs, mean CTX levels as measured on average 11.3 months (range 6-23) after the last Dmab injection were above the upper limit of premenopausal range (mean +114%, range 28-320%, p = 0.003-0.005 vs previous BPs).

CONCLUSION

The higher CTX levels occurring after Dmab discontinuation in patients who have received multiple injections may be prevented by prior exposure to BPs. This observation may be related to the persistent effects of BPs on bone that prevent the resorbing activity of newly formed osteoclasts when RANK Ligand is no more antagonized.

Changes of Bone-Related Minerals during Denosumab Administration in Post-Menopausal Osteoporotic Patients

Objectives: This retrospective study included 21 patients with primary osteoporosis who were treated with the anti-resorption drug, denosumab. To date, there has been no detailed report on the changes of bone-related minerals after anti-resorption drug therapy. Methods: Twenty-one post-menopausal females were retrospectively enrolled. Serum zinc (Zn), magnesium (Mg), iron (Fe), copper (Cu), grip strength, and estimated glomerular filtration rate (eGFR) were examined at one week and 1, 2, 4, 6, 8, 10, and 12 months. Lumbar spine (L1-4) bone mineral density (L-BMD) and bilateral total hip BMD (H-BMD) were examined before and at 4, 8, and 12 months after treatment commencement. Results: Serum Zn tended to decrease at one week and one month, and tended to increase during 10 to 12 months. Serum Cu maintained during zero to eight months, then decreased at 10 and 12 months. Serum Fe gradually increased after four months. Serum Mg sharply increased at one week, then decreased further. Grip strength increased for two months, then slightly decreased and maintained 4 to 12 months. eGFR almost maintained for zero to eight months, then slightly decreased thereafter. L-BMD values significantly increased at eight (5.8%) (p < 0.01) and 12 months (9.8%) (p < 0.01). H-BMD increased during the period (at 12 months: 3.7%). Conclusions: These results suggest that at later phases of denosumab therapy, Zn and Fe tended to increase while Mg tended to decrease, all of which are important for bone metabolism. Thus, denosumab might improve Zn and Fe metabolism, and thereby likely increase BMD. Since denosumab may not improve Mg, it is better to obtain Mg supplementation during the therapy.

Cost-effectiveness of denosumab versus zoledronic acid for preventing skeletal-related events in the Czech Republic

AIMS

This study assessed the cost-effectiveness of the subcutaneous RANKL inhibitor, denosumab, vs the intravenous bisphosphonate, zoledronic acid, for the prevention of skeletal-related events (SREs) in patients with prostate cancer, breast cancer, and other solid tumors (OST) in the Czech Republic.

MATERIALS AND METHODS

A lifetime Markov model was developed to compare the effects of denosumab and zoledronic acid on costs (including drug costs and administration, patient management, SREs, and adverse events), quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios from a national payer perspective. Different discount rates, time horizons, SRE rates, distributions, and nature (asymptomatic vs all SREs), and the inclusion of treatment discontinuation were considered in scenario analyses. The robustness of the model was tested using deterministic and probabilistic sensitivity analyses.

RESULTS

Across tumor types, denosumab was associated with fewer SREs, improved QALYs, and higher total costs over a lifetime. The incremental cost per QALY gained for denosumab vs zoledronic acid was 382,673 CZK for prostate cancer, 408,450 CZK for breast cancer, and 608,133 CZK for OST. Incremental costs per SRE avoided for the same tumor type were 54,007 CZK, 51,765 CZK, and 94,426 CZK, respectively. In scenario analyses, the results remained similar to baseline, when different discount rates and time horizons were considered. At a non-official willingness-to-pay threshold of 1.2 million CZK, the probabilities of denosumab being cost-effective vs zoledronic acid were 0.64, 0.67, and 0.49 for prostate cancer, breast cancer, and OST, respectively.

LIMITATIONS

The SRE rates used were obtained from clinical trials; studies suggest rates may be higher in clinical practice. Additional evidence on real-world SRE rates could further improve the accuracy of the modeling.

CONCLUSIONS

Compared with zoledronic acid, denosumab provides a cost-effective treatment option for the prevention of SREs in patients with prostate cancer, breast cancer, and OST in the Czech Republic.

Denosumab: Current Use in the Treatment of Primary Bone Tumors

Denosumab, a human monoclonal antibody that inhibits bone resorption by binding on the receptor activator of the nuclear factor kappa-β ligand, has recently emerged as an additional option in the treatment of musculoskeletal osteolytic tumors. This article focuses on the recent literature regarding the effectiveness of denosumab in the management of giant cell tumor, multiple myeloma, aneurysmal bone cyst, and osteosarcoma. The mechanism of action of denosumab in the management of these tumors and the associated side effects are discussed in detail. [ Orthopedics. 2017; 40(4):204-210.].

Safety Observations With 3 Years of Denosumab Exposure: Comparison Between Subjects Who Received Denosumab During the Randomized FREEDOM Trial and Subjects Who Crossed Over to Denosumab During the FREEDOM Extension

Denosumab is a fully human monoclonal antibody against receptor activator of NF-κB ligand (RANKL) that decreases osteoclast formation, function and survival, and is approved for the treatment of postmenopausal women with osteoporosis at increased or high risk for fracture, among other indications. During the pivotal 3-year fracture trial FREEDOM, denosumab 60 mg subcutaneously every 6 months significantly reduced new vertebral (68%), hip (40%), and nonvertebral (20%) fractures; increased bone mineral density (BMD); and reduced bone turnover markers compared with placebo in postmenopausal women with osteoporosis. Questions have arisen regarding imbalances of certain low-frequency adverse events (AEs) observed in FREEDOM, as well as the top 5 most frequent adverse reactions listed in the United States prescribing information (USPI; back pain, pain in extremity, musculoskeletal pain, hypercholesterolemia, and cystitis). We examined the incidences of these AEs in women who originally received placebo during FREEDOM and then received denosumab for up to 3 years during the FREEDOM Extension (Crossover Group). This provided a unique opportunity for comparison with the original 3-year denosumab FREEDOM observations. We also examined the incidences of these AEs over 6 years of denosumab treatment (Long-term Group; ie, comparing a second 3 years of treatment with findings in the first 3 years). There was no indication of increasing trends regarding the imbalances of either low-frequency AEs or common AEs observed in FREEDOM. © 2017 American Society for Bone and Mineral Research.

Cost-effectiveness of denosumab versus oral alendronate for elderly osteoporotic women in Japan

We constructed a Markov microsimulation model among hypothetical cohorts of community-dwelling elderly osteoporotic Japanese women without prior hip or vertebral fractures over a lifetime horizon. Compared with weekly oral alendronate for 5 years, denosumab every 6 months for 5 years is cost-saving or cost-effective at a conventionally accepted threshold.

INTRODUCTION

The objective of the study was to examine the cost-effectiveness of subcutaneous denosumab every 6 months for 5 years compared with weekly oral alendronate for 5 years in Japan.

METHODS

We calculated incremental cost-effectiveness ratios [ICERs] (2016 US dollars [$] per quality-adjusted life year [QALY]), using a Markov microsimulation model among hypothetical cohorts of community-dwelling osteoporotic Japanese women without prior hip or vertebral fractures at various ages of therapy initiation (65, 70, 75, and 80 years) over a lifetime horizon from three perspectives: societal, healthcare sector, and government.

RESULTS

Denosumab was cost-saving compared with alendronate at ages 75 and 80 years from any of the three perspectives. The ICERs of denosumab compared with alendronate were $25,700 and $5000 per QALY at ages 65 and 70 years from a societal perspective and did not exceed a willingness-to-pay of $50,000 per QALY from the other two perspectives. In deterministic sensitivity analyses, results were sensitive to changes in the effectiveness of denosumab for reducing hip fracture and clinical vertebral fracture and the rate ratio of non-persistence with denosumab compared to alendronate. In probabilistic sensitivity analyses, the probabilities of denosumab being cost-effective compared with alendronate were 89-100% at a willingness-to-pay of $50,000 per QALY.

CONCLUSIONS

Among community-dwelling elderly osteoporotic women in Japan, denosumab every 6 months for 5 years is cost-saving or cost-effective at a conventionally accepted threshold of willingness-to-pay at all ages examined, compared with weekly alendronate for 5 years. This study provides insight to clinicians and policymakers regarding the relative economic value of osteoporosis treatments in elderly women.

Observations following discontinuation of long-term denosumab therapy

Stopping denosumab after 8 years of continued treatment was associated with bone loss during a 1-year observation study in patients who were not prescribed osteoporosis treatment. Bone loss was attenuated in patients who began another osteoporosis therapy. Treatment to prevent bone loss upon stopping denosumab should be considered.

INTRODUCTION

This study aimed to understand osteoporosis management strategies during a 1-year observational follow-up after up to 8 years of denosumab treatment in a phase 2 study.

METHODS

During the observational year, patients received osteoporosis management at the discretion of their physician and returned to the clinic for BMD assessment and completion of an osteoporosis management questionnaire. Incidence of serious adverse events and fractures was collected. Analyses were descriptive.

RESULTS

Of 138 eligible patients, 82 enrolled in and completed the observation study. Most (65 [79%]) did not receive prescription osteoporosis medication, with "my doctor felt I no longer needed a medication" being the most common reason (23 [35%]). Of the 17 patients who took osteoporosis medications, 8 discontinued therapy during the observation study. In patients treated with denosumab for 8 years (N = 52), BMD decreased during the 1-year observation study (6.7% [lumbar spine], 6.6% [total hip]). Those who took osteoporosis medication during the observation study showed a smaller decline in BMD than those who did not. No new safety concerns were identified. Eight patients (9.8%), all of whom had at least one predisposing risk factor, experienced 17 fractures. This included seven patients who experienced one or more vertebral fractures.

CONCLUSIONS

Consistent with denosumab's mechanism of action, treatment cessation led to reversal of the drug's effect on BMD and perhaps fracture risk. For patients who took osteoporosis therapy, bone loss was attenuated. For patients at high fracture risk, switching to another osteoporosis therapy if denosumab is discontinued seems appropriate.

Vitamin D and Calcium Are Required during Denosumab Treatment in Osteoporosis with Rheumatoid Arthritis

The aim of this 12-month retrospective study was to evaluate differences in the outcomes of denosumab alone or denosumab combined with vitamin D and calcium supplementation in patients having osteoporosis (OP) with rheumatoid arthritis (RA). Patients were divided into the denosumab monotherapy group (denosumab group, 22 cases) or denosumab plus vitamin D supplementation group (combination group, 21 cases). We measured serum bone alkaline phosphatase (BAP), N-terminal propeptide of type 1 collagen (P1NP), tartrate-resistant acid phosphatase (TRACP)-5b, and urinary N-terminal telopeptide of type-I collagen (NTX) at baseline, 1 week, and 1, 2, 4, 6, 8, and 12 months. We also assessed bone mineral density (BMD) of the lumbar 1-4 vertebrae (L-BMD) and bilateral total hips (H-BMD) at baseline and 4, 8, and 12 months. Matrix metalloprotanase-3 (MMP-3), Disease Activity Score-28 C-reactive protein (DAS28-CRP), Simplified Disease Activity Index (SDAI), and Health Assessment Questionnaire-Disability Index (HAQ-DI) were assessed before treatment and at 12 months to evaluate RA conditions. The study results showed that BAP, TRACP-5b, and NTX were significantly decreased, but tended to return to pre-treatment levels around 6 and 12 months in both groups. While L-BMD and H-BMD substantially increased in both groups, H-BMD had become significantly higher in the combination group at 12 months (p < 0.01) as compared with the denosumab group. There were no significant differences between the groups regarding MMP-3, DAS28-CRP, SDAI, or HAQ-DI. Compared with denosumab monotherapy, combination therapy of denosumab with vitamin D and calcium significantly increased H-BMD in patients having OP with RA.

[Denosumab in clinical practice : beware before, during and after]

Denosumab is a very effective treatment of osteoporosis, easy to use and very well tolerated. Due to some associated risks, a close clinical follow-up is necessary. Before the first injection, it is necessary to correct hypocalcaemia or vitamin D deficiency when present. Calcemia has to be followed in case of renal insufficiency. Injections of denosumab should be done scrupulously every 6 months (± 3 weeks). Discontinuation of denosumab is associated with a severe rebound effect characterized by increased markers of bone remodeling, a rapid decrease of bone density values, and a risk of multiple spontaneous vertebral fractures. The administration of a potent bisphosphonate (zoledronate, alendronate) minimises or avoids this rebound effect.

Frequency of discontinuation of injectable osteoporosis therapies in US patients over 2 years

Little is known about treatment patterns with injectable osteoporosis therapies. At 12 months, the probability of discontinuation was 69.1% among patients using ibandronate, followed by teriparatide (67.1%), zoledronic acid (59.2%), and denosumab (48.8%). By 24 months, discontinuation was higher for each treatment. The majority of US patients discontinue injectable osteoporosis treatment by the end of the first year following initiation.

INTRODUCTION

This study was designed to assess the frequency of treatment discontinuation over time among patients who initiate injectable osteoporosis therapies.

METHODS

This retrospective observational study utilized an administrative claims database to measure discontinuation of injectable osteoporosis therapy, reported at 6-month intervals over 2 years. Eligible patients were aged ≥55 years, had newly initiated injectable osteoporosis therapy between January 2008 and June 2012, and were continuously enrolled in the health plan for ≥1 year prior to and ≥1.5 years after the date the first injectable medication was received (the index date). Follow-up time ranged from 18 to 24 months. Injectable osteoporosis treatments included in the analysis were denosumab, ibandronate, teriparatide, and zoledronic acid. Discontinuation was assessed using Kaplan-Meier survival analysis and was defined at each time point as the percentage of patients who did not receive the dose scheduled for that time point. A 90-day grace period was allowed to accommodate flexibility in the scheduling of post-index re-administrations. Sensitivity analyses assessed discontinuation using grace periods of 60 and 30 days.

RESULTS

A total of 4756 patients met the inclusion criteria for the study, with 617 utilizing denosumab, 233 ibandronate, 778 teriparatide, and 3128 zoledronic acid. At 12 months, discontinuation was highest among patients using ibandronate (69.1%), followed by teriparatide (67.1%), zoledronic acid (59.2%), and denosumab (48.8%). By 24 months, discontinuation was higher for each treatment: 87.5% for ibandronate, 87.9% for teriparatide, 79.8% for zoledronic acid, and 64.3% for denosumab.

CONCLUSIONS

The majority of US patients discontinue injectable osteoporosis treatment by the end of the first year following initiation.

Baseline Characteristics and Changes in Bone Mineral Density T-Scores of Bulgarian Women with Postmenopausal Osteoporosis Receiving Denosumab in Routine Clinical Practice

BACKGROUND

Postmenopausal osteoporosis (PMO) is common among women over 50 years of age and is associated with an increased risk of fracture. Bone-targeted agents, such as denosumab, can reduce fracture risk in patients with PMO.

OBJECTIVE

The aim was to describe baseline characteristics and changes in bone mineral density (BMD) T-scores among women with PMO receiving denosumab in Bulgaria.

METHODS

This multicenter chart review included women with PMO receiving denosumab for ≥1 year in Bulgaria (October 2011-August 2013). Participants were required to have a baseline BMD T-score of ≤-2.5 standard deviations (SDs) at one or more skeletal sites.

RESULTS

Overall, 222 women were included. The mean (SD) age at denosumab initiation was 64.2 (8.5) years; 26.6% reported a previous osteoporotic fracture and 6.8% a previous hip fracture. Only half of those reporting a previous fracture (49.2%) had received prior osteoporosis therapy. At baseline, mean (SD) BMD T-scores were lumbar spine -3.2 SD (0.6 SD), total hip -2.3 SD (0.8 SD), and femoral neck -2.7 SD (0.7 SD). After 1 year of denosumab treatment, scores increased significantly at all three sites, reaching -2.7 SD (0.6 SD), -2.1 SD (0.9 SD), and -2.4 SD (0.7 SD), respectively (all p < 0.0001 vs. baseline). No serious adverse drug reactions were identified.

CONCLUSION

Denosumab is usually prescribed in women with PMO at high fracture risk. In the patients who were persistent with treatment at 1 year, denosumab was well tolerated and effective at increasing BMD T-scores at several skeletal sites.

Hypocalcaemia after denosumab in older people following fracture

Hypocalcaemia following denosumab therapy can be observed in older adults. This is more common if their pre-treatment corrected serum calcium concentrations are less than 2.28 mmol/L. Denosumab remains a safe treatment in older people but we recommend a cautious approach in people at risk.

INTRODUCTION

Previous studies have indicated that denosumab, an anti-RANK ligand (RANKL) monoclonal antibody, for treatment of osteoporosis is well-tolerated. There is little data specifically regarding its adverse effect profile in a hospitalised older person. Primarily, this study wished to determine the frequency of hypocalcaemia following denosumab administration in older people admitted to hospital following fracture. Secondarily, this study wished to determine any associations that may predict the development of hypocalcaemia.

METHODS

This was a prospective study of 33 participants using a paired study design aged 70 years old or more with fragility fractures who were given denosumab in a rehabilitation hospital in Sydney. The primary outcome was the frequency of hypocalcaemia. Hypocalcaemia was defined as corrected serum concentration of less than 2.20 mmol/L on day 14 after denosumab administration.

RESULTS

Of the 33 participants with a mean age of 84.6 ± 1.2 years old, 5 participants (15.2 %) developed hypocalcaemia post injection. A paired t test showed a mean difference between the baseline and post injection calcium concentrations to be 0.059 mmol/L (95 %CI 0.020-0.098; t = 3.080, p = 0.004). Regression analysis showed that pre-denosumab serum calcium concentration correlated with the post-denosumab injection calcium concentration (R = 0.631, 95 %CI 0.288-0.977; p = 0.001). No other variables were significant. Further, a baseline serum calcium concentration of 2.28 mmol/L was able to predict post-denosumab hypocalcaemia with a sensitivity of 80 % and specificity of 86 %.

CONCLUSIONS

Denosumab is a relatively safe treatment of osteoporosis. This study shows that hypocalcaemia following denosumab therapy can be observed in older adults. Clinicians should be aware of this adverse effect when using denosumab in the older people.

Severe Rebound-Associated Vertebral Fractures After Denosumab Discontinuation: 9 Clinical Cases Report

CONTEXT

Denosumab inhibits bone resorption, increases bone mineral density, and reduces fracture risk. Denosumab was approved for the treatment of osteoporosis and the prevention of bone loss in some oncological situations. Denosumab discontinuation is associated with a severe bone turnover rebound (BTR) and a rapid loss of bone mineral density. The clinical consequences of the BTR observed after denosumab discontinuation are not known.

CASES DESCRIPTION

We report 9 women who presented 50 rebound-associated vertebral fractures (RAVFs) after denosumab discontinuation. A broad biological and radiological assessment excluded other causes than osteoporosis. These 9 cases are unusual and disturbing for several reasons. First, all vertebral fractures (VFs) were spontaneous, and most patients had a high number of VFs (mean = 5.5) in a short period of time. Second, the fracture risk was low for most of these women. Third, their VFs occurred rapidly after last denosumab injection (9-16 months). Fourth, vertebroplasty was associated with a high number of new VFs. All the observed VFs seem to be related to denosumab discontinuation and unlikely to the underlying osteoporosis or osteopenia. We hypothesize that the severe BTR is involved in microdamage accumulation in trabecular bone and thus promotes VFs.

CONCLUSION

Studies are urgently needed to determine 1) the pathophysiological processes involved, 2) the clinical profile of patients at risk for RAVFs, and 3) the management and/or treatment regimens after denosumab discontinuation. Health authorities, physicians, and patients must be aware of this RAVF risk. Denosumab injections must be scrupulously done every 6 months but not indefinitely.

[Osteoporosis treatment can be discontinued based on an individual assessment]

In most patients, treatment of osteoporosis is a long-term challenge. Because alendronate and zoledronic acid accumulate in bone with some persistent antifracture efficacy after therapy, it is reasonable to consider a "drug holiday" for low-risk patients. It is recommended that the duration and length of drug holiday should be individualized for each patient. For all other bisphosphonates data are limited. For other antiresorptive and anabolic agents "drug holiday" is not recommended.

Denosumab: targeting the RANKL pathway to treat rheumatoid arthritis

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic inflammatory disorder characterized by focal pathologic bone resorption due to excessive activity of osteoclasts (OC). Receptor activator of nuclear factor kappa B ligand (RANKL) is essential for the proliferation, differentiation, and survival of OC. Denosumab (DMab) is a humanized monoclonal antibody that binds to RANKL with high affinity and blocks its subsequent association with its receptor RANK on the surface of OC precursors. Area covered: The authors review the molecular and cellular mechanisms underlying therapeutic applications of DMab, provide recent highlights on pharmacology, efficacy and safety of DMab, and discuss the potential of DMab as a novel therapeutic option for the treatment of rheumatoid arthritis. Expert opinion: Clinical results suggest that DMab is efficient both in systemic and articular bone loss in RA with limited side effects. Diminished bone erosion activity was also noted in RA patients on corticosteroids and bisphosphonates. Combination of DMab with an anti-TNF agent was not associated with increased infection rates. Collectively, these data indicate that DMab, in combination with methotrexate and possibly other conventional synthetic Disease Modifying Anti-Rheumatic Drugs (csDMARDs), is an effective, safe and cost-effective option for the treatment of RA.

The effects of switching daily teriparatide to oral bisphosphonates or denosumab in patients with primary osteoporosis

The aim of this 12-month, observational study was to compare the effects of switching daily teriparatide (TPTD) to oral bisphosphonates (BP) therapy or denosumab (DMAb) therapy in patients with primary osteoporosis. Patients [n = 78; 71 postmenopausal women and seven men; mean age 76.3 (64-94) years; mean duration of prior daily TPTD therapy 20.1 (6-24) months] were allocated to either the (1) "switch-to-BP" group [n = 36; weekly alendronate 35 mg (n = 19), weekly risedronate 17.5 mg (n = 12), monthly minodronate 50 mg (n = 5)]; or (2) "switch-to-DMAb" group (n = 42; 60 mg sc every 6 months) based on each physicians' decision. Changes in bone mineral density (BMD) and serum bone turnover markers were monitored every 6 months. No significant difference was observed in baseline clinical characteristics between the groups. After 12 months, the increase in BMD was significantly greater in the switch-to-DMAb group compared to the switch-to-BP group: lumbar spine (6.2 vs. 2.6 %; P < 0.01), total hip (4.2 vs. 1.1 %; P < 0.05), and femoral neck (3.5 vs. 1.4 %; P < 0.05). In addition, the patients in the switch-to-DMAb group showed a significant decrease compared to those in the switch-to-BP group in TRACP-5b (-55.8 vs. -32.8 %; P < 0.01) and ucOC (-85.5 vs. -65.0 %; P < 0.001), while no significant difference was observed in PINP (-67.5 vs. -62.1 %). Switching daily TPTD to DMAb significantly increased BMD and decreased bone resorption marker compared to switching to oral BP at 12 months, and thus may provide an effective sequential treatment option after daily TPTD treatment.

Case-Based Review of Osteonecrosis of the Jaw (ONJ) and Application of the International Recommendations for Management From the International Task Force on ONJ

Osteonecrosis of the jaw (ONJ) has been associated with antiresorptive therapy in both oncology and osteoporosis patients. This debilitating condition is very rare and advances in diagnosis and management may now effectively reduce the risk of its development and offer valuable treatment options for affected patients. This paper provides a case-based review of ONJ and application of the International Task Force on ONJ (referred to as the "Task Force") recommendations for the diagnosis and management of ONJ. The Task Force was supported by 14 international societies and achieved consensus from representatives of these multidisciplinary societies on key issues pertaining to the diagnosis and management of ONJ. The frequency of ONJ in oncology patients receiving oncology doses of bisphosphonate (BP) or denosumab is estimated at 1%-15%, and the frequency in the osteoporosis patient population receiving much lower doses of BP or denosumab is estimated at 0.001%-0.01%. Although the diagnosis of ONJ is primarily clinical, imaging may be helpful in confirming the diagnosis and staging. In those with multiple risk factors for ONJ for whom major invasive oral surgery is being planned, interruption of BP or denosumab therapy (in cancer patients) is advised, if possible, before surgery, until the surgical site heals. Major oral surgery in this context could include multiple extractions if surgical extractions are required, not simple forceps extractions. ONJ development may be reduced by optimizing oral hygiene and postoperatively using topical and systemic antibiotics as appropriate. Periodontal disease should be managed before starting oncology doses of BP or denosumab. Local debridement may be successful in disease unresponsive to conservative therapy. Successful surgical intervention has been reported in those with stage 3 disease; less severe disease is best managed conservatively. Teriparatide may be helpful in healing ONJ lesions and may be considered in osteoporosis patients at a high fracture risk in the absence of contraindications. Resumption of BP or denosumab therapy following healing of ONJ lesions is recommended, and there have not been reports of subsequent local recurrence.

Factors associated with high 24-month persistence with denosumab: results of a real-world, non-interventional study of women with postmenopausal osteoporosis in Germany, Austria, Greece, and Belgium

Persistence with osteoporosis therapy is vital for fracture prevention. This non-interventional study of postmenopausal women receiving denosumab in Germany, Austria, Greece, and Belgium found that persistence with denosumab remains consistently high after 24 months in patients at high risk of fracture.

PURPOSE

Continued persistence with osteoporosis therapy is vital for fracture prevention. This non-interventional study of clinical practice evaluated medication-taking behavior of postmenopausal women receiving denosumab in Germany, Austria, Greece, and Belgium and factors influencing persistence.

METHODS

Subcutaneous denosumab (60 mg every 6 months) was assigned according to prescribing information and local guidelines before and independently of enrollment; outcomes were recorded during routine practice for up to 24 months. Persistence was defined as receiving the subsequent injection within 6 months + 8 weeks of the previous injection and adherence as administration of subsequent injections within 6 months ± 4 weeks of the previous injection. Medication coverage ratio (MCR) was calculated as the proportion of time a patient was covered by denosumab. Associations between pre-specified baseline covariates and 24-month persistence were assessed using multivariable logistic regression.

RESULTS

The 24-month analyses included 1479 women (mean age 66.3-72.5 years) from 140 sites; persistence with denosumab was 75.1-86.0%, adherence 62.9-70.1%, and mean MCR 87.4-92.4%. No covariate had a significant effect on persistence across all four countries. For three countries, a recent fall decreased persistence; patients were generally older with chronic medical conditions. In some countries, other covariates (e.g., older age, comorbidity, immobility, and prescribing reasons) decreased persistence. Adverse drug reactions were reported in 2.3-6.9% patients.

CONCLUSIONS

Twenty-four-month persistence with denosumab is consistently high among postmenopausal women in Europe and may be influenced by patient characteristics. Further studies are needed to identify determinants of low persistence.

[Drug-induced osteonecrosis of the jaw - not just bisphosphonates]

Metastatic bone disease and osteoporosis have a large impact on quality of life and are associated with the development of skeletal-related events (SREs), such as fractures and spinal cord compression. Pharmacologic managing of metastatic bone disease and osteoporosis typically involves antiresorptive agents such as bisphosphonates and RANKL inhibitors. Undesired adverse effects resulting from the use of these drugs include osteonecrosis of the jaw (ONJ). Dentoalveolar surgery, particularly tooth extraction, appears to increase the risk of ONJ. However, spontaneous events were also documented. Therefore, it is of upmost importance for the general practitioner to have updated knowledge in order to prevent and early diagnose ONJ. We present a case of a metastatic breast cancer patient who spontaneously developed ONJ following the use of Denosumab, a monoclonal RANKL antibody.

Ovarian stimulation in young adult cancer survivors on targeted cancer therapies

OBJECTIVE

To describe a clinical approach to and outcomes of IVF in reproductive-aged cancer survivors receiving targeted cancer therapies.

DESIGN

Case report.

SETTING

Not applicable.

PATIENT(S)

The first case is of a female patient with metastatic lung cancer receiving long-term crizotinib, an anaplastic lymphoma kinase inhibitor. The second case is of a female patient with metastatic colon cancer receiving long-term denosumab, a RANKL antibody. Both patients presented desiring fertility.

INTERVENTION(S)

In vitro fertilization.

MAIN OUTCOME MEASURE(S)

Live birth and embryo banking.

RESULT(S)

The potential impact of targeted therapy on oocytes and pregnancy was investigated via literature review and pharmaceutical company inquiries. After oncologic, fertility, and psychological counseling, both survivors underwent ovarian stimulation, IVF, and preimplantation genetic screening. One couple achieved live births of dizygotic twins via gestational surrogacy. The second couple froze one euploid blastocyst for future fertility. Both survivors are stable from their cancer standpoints.

CONCLUSION(S)

Successful fertility treatments are possible in the context of exposure to crizotinib and denosumab.

Rebound-associated vertebral fractures after discontinuation of denosumab-from clinic and biomechanics

Rebound-associated vertebral fractures may follow treatment discontinuation of highly potent reversible bone antiresorptives, resulting from the synergy of rapid bone resorption and accelerated microdamage accumulation in trabecular bone.

INTRODUCTION

The purposes of this study are to characterize rebound-associated vertebral fractures following the discontinuation of a highly potent reversible antiresorptive therapy based on clinical observation and propose a pathophysiological rationale.

METHODS

This study is a case report of multiple vertebral fractures early after discontinuation of denosumab therapy in a patient with hormone receptor-positive non-metastatic breast cancer treated with an aromatase inhibitor.

RESULTS

Discontinuation of highly potent reversible bone antiresorptives such as denosumab may expose patients to an increased fracture risk due to the joined effects of absent microdamage repair during therapy followed by synchronous excess activation of multiple bone remodelling units at the time of loss-of-effect. We suggest the term rebound-associated vertebral fractures (RVF) for this phenomenon characterized by the presence of multiple new clinical vertebral fractures, associated with either no or low trauma, in a context consistent with the presence of high bone turnover and rapid loss of lumbar spine bone mineral density (BMD) occurring within 3 to 12 months after discontinuation (loss-of-effect) of a reversible antiresorptive therapy in the absence of secondary causes of bone loss or fractures. Unlike atypical femoral fractures that emerge from failure of microdamage repair in cortical bone with long-term antiresorptive treatment, RVF originate from the synergy of rapid bone resorption and accelerated microdamage accumulation in trabecular bone triggered by the discontinuation of highly potent reversible antiresorptives.

CONCLUSIONS

Studies are urgently needed to i) prove the underlying pathophysiological processes suggested above, ii) establish the predictive criteria exposing patients to an increased risk of RVF, and iii) determine appropriate treatment regimens to be applied in such patients.

Severe spontaneous vertebral fractures after denosumab discontinuation: three case reports

Osteoporosis treatments are usually given for a limited period of time in order to balance benefits and risks. We report three cases of postmenopausal women without any previous fragility fracture who presented severe spontaneous vertebral fractures after denosumab discontinuation. We think that the occurrence of these fractures could be explained by the severe rebound effect observed after denosumab discontinuation and that a consensus regarding the end of treatment with denosumab has to be defined.

Assessment of off-label use of denosumab 60 mg injection during the early postmarketing period using health insurance claims data

Off-label use of denosumab 60 milligram (mg) injection was assessed within an administrative claims database. The completeness of claims to assess off-label use was investigated with medical record review. Potential denosumab 60 mg off-label use was observed based on claims, but many had evidence of on-label indications based on medical record review.

INTRODUCTION

Denosumab 60 mg injection is approved in the USA to treat patients at high fracture risk due to postmenopausal osteoporosis, male osteoporosis, and hormone therapy for the treatment of prostate and breast cancers. Its RANK ligand-inhibiting effect makes it a candidate for the off-label treatment of other conditions mediated by the rate of bone resorption by osteoclasts. To better understand its utilization patterns, we assessed off-label use of denosumab 60 mg within an administrative claims database.

METHODS

Definite, probable, and possible denosumab 60 mg users were identified during the early postmarketing period within a claims database of a US healthcare insurer. Medical record review confirmed a sample of these users. Off-label use among definite and probable users and all chart-confirmed users was classified using claims-derived age, dose interval, and diagnosis and treatment received relative to the administration date. Among chart-confirmed users classified as off-label, patient characteristics related to treatment indication were abstracted from medical records to investigate the completeness of claims to study off-label medication use.

RESULTS

Off-label use was identified based on claims in approximately 25 % of definite and probable denosumab 60 mg users and 35 % of chart-confirmed users. Medical record review identified evidence of on-label indications in 81 % of chart-confirmed users classified as off-label in claims.

CONCLUSIONS

Many of the off-label denosumab 60 mg users had diagnoses or treatment consistent with on-label indications based on medical record review, suggesting these are under-recorded in claims data. It is warranted to be cautious when using administrative databases to assess off-label medication use.

Pain and analgesic use associated with skeletal-related events in patients with advanced cancer and bone metastases

PURPOSE

Bone metastases secondary to solid tumors increase the risk of skeletal-related events (SREs), including the occurrence of pathological fracture (PF), radiation to bone (RB), surgery to bone (SB), and spinal cord compression (SCC). The aim of this study was to evaluate the impact of SREs on patients' pain, analgesic use, and pain interference with daily functioning.

METHODS

Data were combined from patients with solid tumors and bone metastases who received denosumab or zoledronic acid across three identically designed phase 3 trials (N = 5543). Pain severity (worst pain) and pain interference were assessed using the Brief Pain Inventory at baseline and each monthly visit. Analgesic use was quantified using the Analgesic Quantification Algorithm.

RESULTS

The proportion of patients with moderate/severe pain and strong opioid use generally increased in the 6 months preceding an SRE and remained elevated, while they remained relatively consistent over time in patients without an SRE. Regression analysis indicated that all SRE types were significantly associated with an increased risk of progression to moderate/severe pain and strong opioid use. PF, RB, and SCC were associated with significantly greater risk of pain interference overall. Results were similar for pain interference with emotional well-being. All SRE types were associated with significantly greater risk of pain interference with physical function.

CONCLUSIONS

SREs are associated with increased pain and analgesic use in patients with bone metastases. Treatments that prevent SREs may decrease pain and the need for opioid analgesics and reduce the impact of pain on daily functioning.

Effect of Denosumab Administration on Lumbar Vertebral Strength of Patients with Vertebral Bony Metastases: Preliminary Study

The purpose of this study was to examine the usefulness of administration of denosumab (antibody against tumor necrosis factor superfamily member 11) as a preventative therapy for skeletal-related events (SREs), such as fracture or paralysis, by computed-tomography (CT)-based on the finite element method (FEM). Patients who had undergone treatment for vertebral metastases with denosumab administration from December 2013 to August 2015 at our Institution were reviewed. We investigated patient data at the time before denosumab administration and at 1, 3 and 6 months using CT. A total of six patients were eligible; four males and two females, with ages ranging from 35 to 73 years, with a mean age of 56 years. Repeated measures analysis of variance showed a significant increase (p=0.0055, F=10.67). To our knowledge, this is the first article to substantiate the effects of the SRE-preventative drug denosumab.

An open-label study in healthy men to evaluate the risk of seminal fluid transmission of denosumab to pregnant partners

AIMS

Denosumab is a fully human monoclonal immunoglobulin G2 antibody that inhibits bone resorption and increases bone mass and strength. The present clinical study assessed serum and seminal fluid pharmacokinetics following a single denosumab dose in healthy men, and evaluated whether denosumab in seminal fluid poses any risk to a fetus in the event of unprotected sexual intercourse with a pregnant partner.

METHODS

An open-label, single-dose study in 12 healthy men was conducted over a 106-day period. Subjects received a single subcutaneous dose of 60-mg denosumab on day 1. Serum and seminal fluid samples were collected at specified time points to assess denosumab pharmacokinetics. Adverse events were recorded.

RESULTS

Denosumab was measurable at low concentrations in seminal fluid (~2% of serum concentrations). The mean [standard deviation (SD)] maximum observed drug concentration (Cmax ) was 6170 (2070) ng ml(-1) (serum) and 100 (81.9) ng ml(-1) (seminal fluid). The median time to Cmax (tmax ) was 8 days (serum) and 21 days (seminal fluid). The mean (SD) area under the plasma concentration-time curve (AUC) from time zero to the time of the last quantifiable concentration (AUClast ) was 333 000 (122 000) day•ng ml(-1) (serum) and 5220 (4880) day•ng ml(-1) (seminal fluid). The mean (SD) Cmax and AUC ratios between seminal fluid and serum were 0.0217 (0.0154) and 0.0170 (0.0148), respectively. Using conservative assumptions for ejaculate volume (6 ml), vaginal absorption (100%) and placental transfer (100%), the measured mean denosumab seminal fluid Cmax would result in fetal exposure that was more than 110 times below the preclinically derived 'no effect level' for denosumab.

CONCLUSIONS

These results indicate a negligible risk to a fetus exposed to denosumab via seminal fluid transfer to a pregnant partner.

[Pharmacokinetics of anti-RANKL antibody drugs:Denosumab.]

Antibody drug is a kind of glycoprotein which molecular weight is over one hundred thousand. The number of pharmaceutical approval of antibody drug has been increasing in recent years. In terms of a working mechanism and pharmacokinetics, antibody drug is markedly different from existing low molecular weight drugs. In prospect, about body kinetics is the same. This paper describes general features of antibody drug mainly about internal kinetics in the first half. In the last half, body kinetics of human anti-RANKL monoclonal antibody called Denosumab and body kinetics changes in special population are outlined.

The effect of 8 or 5 years of denosumab treatment in postmenopausal women with osteoporosis: results from the FREEDOM Extension study

The FREEDOM study and its Extension provide long-term information about the effects of denosumab for the treatment of postmenopausal osteoporosis. Treatment for up to 8 years was associated with persistent reduction of bone turnover, continued increases in bone mineral density, low fracture incidence, and a favorable benefit/risk profile.

INTRODUCTION

This study aims to report the results through year 5 of the FREEDOM Extension study, representing up to 8 years of continued denosumab treatment in postmenopausal women with osteoporosis.

METHODS

Women who completed the 3-year FREEDOM study were eligible to enter the 7-year open-label FREEDOM Extension in which all participants are scheduled to receive denosumab, since placebo assignment was discontinued for ethical reasons. A total of 4550 women enrolled in the Extension (2343 long-term; 2207 cross-over). In this analysis, women in the long-term and cross-over groups received denosumab for up to 8 and 5 years, respectively.

RESULTS

Throughout the Extension, sustained reduction of bone turnover markers (BTMs) was observed in both groups. In the long-term group, mean bone mineral density (BMD) continued to increase significantly at each time point measured, for cumulative 8-year gains of 18.4 and 8.3 % at the lumbar spine and total hip, respectively. In the cross-over group, mean BMD increased significantly from the Extension baseline for 5-year cumulative gains of 13.1 and 6.2 % at the lumbar spine and total hip, respectively. The yearly incidence of new vertebral and nonvertebral fractures remained low in both groups. The incidence of adverse and serious adverse events did not increase over time. Through Extension year 5, eight events of osteonecrosis of the jaw and two events of atypical femoral fracture were confirmed.

CONCLUSIONS

Denosumab treatment for up to 8 years was associated with persistent reductions of BTMs, continued BMD gains, low fracture incidence, and a consistent safety profile.

Further reductions in nonvertebral fracture rate with long-term denosumab treatment in the FREEDOM open-label extension and influence of hip bone mineral density after 3 years

Limited data exist on the efficacy of long-term therapies for osteoporosis. In osteoporotic postmenopausal women receiving denosumab for 7 years, nonvertebral fracture rates significantly decreased in years 4-7 versus years 1-3. This is the first demonstration of a further benefit on fracture outcomes with long-term therapy for osteoporosis.

INTRODUCTION

This study aimed to evaluate whether denosumab treatment continued beyond 3 years is associated with a further reduction in nonvertebral fracture rates.

METHODS

Participants who completed the 3-year placebo-controlled Fracture REduction Evaluation of Denosumab in Osteoporosis every 6 Months (FREEDOM) study were invited to participate in an open-label extension. The present analysis includes 4,074 postmenopausal women with osteoporosis (n = 2,343 long-term; n = 1,731 cross-over) who enrolled in the extension, missed ≤1 dose during their first 3 years of denosumab treatment, and continued into the fourth year of treatment. Comparison of nonvertebral fracture rates during years 1-3 of denosumab with that of the fourth year and with the rate during years 4-7 was evaluated.

RESULTS

For the combined group, the nonvertebral fracture rate per 100 participant-years was 2.15 for the first 3 years of denosumab treatment (referent) and 1.36 in the fourth year (rate ratio [RR] = 0.64; 95 % confidence interval (CI) = 0.48 to 0.85, p = 0.003). Comparable findings were observed in the groups separately and when nonvertebral fracture rates during years 1-3 were compared to years 4-7 in the long-term group (RR = 0.79; 95 % CI = 0.62 to 1.00, p = 0.046). Fracture rate reductions in year 4 were most prominent in subjects with persisting low hip bone mineral density (BMD).

CONCLUSIONS

Denosumab treatment beyond 3 years was associated with a further reduction in nonvertebral fracture rate that persisted through 7 years of continuous denosumab administration. The degree to which denosumab further reduces nonvertebral fracture risk appears influenced by the hip bone density achieved with initial therapy.

How Long to Treat with Denosumab

Chronic diseases typically require long-term treatment. Osteoporosis is a chronic disease in which fracture risk is high, and treatment is required to prevent fragility fractures. Denosumab is a fully human monoclonal antibody that inhibits RANK ligand, a powerful bone-resorbing cytokine. It is approved for individuals with osteoporosis who are at high risk for fracture. Clinical trial results confirm that denosumab is effective over the long term and has an excellent safety profile. In patients at high risk for osteoporotic fracture, therefore, long-term treatment with denosumab appears to present an attractive benefit profile.

Denosumab in treatment-naïve and pre-treated with zoledronic acid postmenopausal women with low bone mass: Effect on bone mineral density and bone turnover markers

PURPOSE

To compare denosumab-induced changes in lumbar spine (LS) and femoral neck (FN) bone mineral density (BMD), bone markers and free soluble receptor activator of nuclear factor kappaB ligand (sRANKL) between treatment naïve postmenopausal women with low bone mass (naïve group) and those who were previously treated with a single zoledronic acid infusion (post-Zol group).

PROCEDURES

Procollagen type 1N-terminal propeptide (P1NP), C-terminal cross-linking telopeptide of type 1 collagen (CTx) and sRANKL levels were measured in serum samples obtained at baseline and 3, 6 and 12months after denosumab initiation. LS and FN BMD were measured at baseline and 12months.

RESULTS

LS and FN BMD increased significantly in both naïve and post-Zol group (p<0.001 and p=0.025 vs. p<0.001 and p=0.017, respectively). Despite the higher P1NP and CTx levels in naïve patients at baseline (both p<0.001), denosumab caused comparable decreases in both groups at month 3, which returned to post-Zol group baseline levels at month 6 and 12 in all patients. Similarly, sRANKL levels decreased significantly at month 3 in both groups and returned to baseline levels at months 6 and 12.

CONCLUSIONS

In patients previously treated with zoledronic acid, sequential denosumab treatment is effective in terms of BMD increases and bone turnover suppression. Despite the lower baseline levels in patients pre-treated with zoledronic acid, bone markers are similarly decreased in both groups following denosumab administration and maintain their reversibility. Denosumab reversibly suppresses endogenous free sRANKL levels in both naïve and zoledronic acid pre-treated patients.

Persistence, adherence, and medication-taking behavior in women with postmenopausal osteoporosis receiving denosumab in routine practice in Germany, Austria, Greece, and Belgium: 12-month results from a European non-interventional study

Persistence with and adherence to osteoporosis therapy are critical for fracture reduction. This non-interventional study is evaluating medication-taking behavior of women with postmenopausal osteoporosis (PMO) receiving denosumab in Germany, Austria, Greece, and Belgium. Patients were representative of the PMO population and highly persistent with and adherent to denosumab at 12 months.

INTRODUCTION

Persistence with and adherence to osteoporosis therapy are important for optimal treatment efficacy, namely fracture reduction. This ongoing, non-interventional study will evaluate medication-taking behavior of women with postmenopausal osteoporosis (PMO) receiving denosumab in routine practice in four European countries.

METHODS

The study enrolled women who had been prescribed subcutaneous denosumab (60 mg every 6 months) in accordance with prescribing information and local guidelines. Persistence was defined as receiving the subsequent injection within 6 months + 8 weeks of the previous injection. Adherence was defined as receiving two consecutive injections within 6 months ± 4 weeks of each other. Medication coverage ratio (MCR) was calculated using the time a patient was covered with denosumab, as assessed from prescription records. Treatment was assigned prior to and independently of enrollment; outcomes are recorded during routine practice.

RESULTS

These planned 12-month interim analyses included data from 1500 patients from 141 sites. Mean age was 66.4-72.4 years, mean baseline total hip T-scores ranged from -2.0 to -2.1 and femoral neck T-scores from -2.2 to -2.6, and 30.7-62.1% of patients had prior osteoporotic fracture. Persistence was 87.0-95.3%, adherence 82.7-89.3%, and MCR 91.3-95.4%. In a univariate analysis, increased age, decreased mobility, and increased distance to the clinic were associated with significantly decreased persistence; parental history of hip fracture was associated with significantly increased persistence.

CONCLUSIONS

These data extend the real-world evidence regarding persistence with and adherence to denosumab, both of which are critical for favorable clinical outcomes, including fracture risk reduction.

Persistence with denosumab and persistence with oral bisphosphonates for the treatment of postmenopausal osteoporosis: a retrospective, observational study, and a meta-analysis

The objectives of this study were to estimate persistence with denosumab and put these results in context by conducting a review of persistence with oral bisphosphonates. Persistence with denosumab was found to be higher than with oral bisphosphonates.

PURPOSE

This study had two objectives: to analyse persistence in Swedish women initiating denosumab for treatment of postmenopausal osteoporosis (PMO) and to put these findings in context by conducting a literature review and meta-analysis of persistence data for oral bisphosphonates.

METHODS

The study used the Swedish Prescribed Drug Register and included women aged at least 50 years initiating denosumab between May 2010 and July 2012. One injection of denosumab was defined as 6-month persistence. Women were considered persistent for another 6 months if they filled their next prescription within 6 months + 56 days and survival analysis applied to the data. A literature search was conducted in PubMed to identify retrospective studies of persistence with oral bisphosphonates and pooled persistence estimates were calculated using a random-effects model.

RESULTS

The study identified 2,315 women who were incident denosumab users. Mean age was 74 years and 61% had been previously treated for PMO. At 12 and 24 months, persistence with denosumab was 83% (95% CI, 81-84%) and 62% (95% CI, 60-65%), respectively. The literature search identified 40 articles for inclusion in the meta-analysis. At 12 and 24 months, persistence with oral bisphosphonates ranged from 10% to 78% and from 16% to 46%, with pooled estimates of 45% and 30%, respectively.

CONCLUSION

These data from the Swedish Prescribed Drug Register and literature review suggest that persistence was higher with denosumab than with oral bisphosphonates.

Bone Tissue Properties Measurement by Reference Point Indentation in Glucocorticoid-Induced Osteoporosis

Glucocorticoids, widely used in inflammatory disorders, rapidly increase bone fragility and, therefore, fracture risk. However, common bone densitometry measurements are not sensitive enough to detect these changes. Moreover, densitometry only partially recognizes treatment-induced fracture reductions in osteoporosis. Here, we tested whether the reference point indentation technique could detect bone tissue property changes early after glucocorticoid treatment initiation. After initial laboratory and bone density measurements, patients were allocated into groups receiving calcium + vitamin D (Ca+D) supplements or anti-osteoporotic drugs (risedronate, denosumab, teriparatide). Reference point indentation was performed on the cortical bone layer of the tibia by a handheld device measuring bone material strength index (BMSi). Bone mineral density was measured by dual-energy X-ray absorptiometry (DXA). Although Ca+D-treated patients exhibited substantial and significant deterioration, risedronate-treated patients exhibited no significant change, and both denosumab- and teriparatide-treated participants exhibited significantly improved BMSi 7 weeks after initial treatment compared with baseline; these trends remained stable for 20 weeks. In contrast, no densitometry changes were observed during this study period. In conclusion, our study is the first to our knowledge to demonstrate that reference point indentation is sensitive enough to reflect changes in cortical bone indentation after treatment with osteoporosis therapies in patients newly exposed to glucocorticoids.

Giant cell tumor: rapid recurrence after cessation of long-term denosumab therapy

We report a case of rapid recurrence of a giant cell tumor (GCT) of the distal radius in a 24-year-old woman following the cessation of long-term denosumab therapy. GCT of bone is a histologically benign tumor with multinucleated giant cells on a background of mononuclear giant cells usually presenting as a well-defined epi-metaphyseal lytic lesion without sclerotic margins. Denosumab, a monoclonal antibody to the receptor activator of nuclear factor kappa-B ligand (RANKL), has proven to be an effective neoadjuvant treatment for GCT. The tumor in this case had demonstrated a good response with sustained control for over 2 years while on denosumab therapy. However, within 2 months of cessation of therapy, the tumor demonstrated rapid recurrence and progression with growth, osteolysis, and increased soft tissue component. Despite reinitiating denosumab therapy, there was progressive tumor growth and destruction, ultimately necessitating below-the-elbow amputation. This case illustrates the need for maintenance of denosumab therapy for GCT of bone or definitive surgical treatment prior to its cessation.

Three-year denosumab treatment in postmenopausal Japanese women and men with osteoporosis: results from a 1-year open-label extension of the Denosumab Fracture Intervention Randomized Placebo Controlled Trial (DIRECT)

SUMMARY

A 12-month extension phase of DIRECT in Japanese subjects with osteoporosis showed that total 3 years of denosumab treatment in Japanese postmenopausal women and men with osteoporosis was associated with low fracture rates, persistent bone turnover marker (BTM) reductions, continuous bone mineral density (BMD) increases, and a favorable overall benefit/risk profile.

INTRODUCTION

The DIRECT trial demonstrated that 2 years of treatment with denosumab 60 mg subcutaneously every 6 months significantly reduced the incidence of vertebral fracture compared to placebo in Japanese postmenopausal women and men with osteoporosis. The purpose of this study is to evaluate the efficacy and safety of denosumab treatment for up to 3 years.

METHODS

This study includes a 2-year randomized, double-blind, placebo-controlled phase and a 1-year open-label extension phase in which all subjects received denosumab. The data correspond to 3 years of denosumab treatment in subjects who received denosumab (long-term group) and 1 year of denosumab treatment in subjects who received placebo (cross-over group) in the double-blind phase.

RESULTS

Eight hundred and ten subjects who completed the double-blind phase enrolled into the extension phase, and 775 subjects completed the study. All subjects received denosumab with daily supplements of calcium and vitamin D. The cumulative 36-month incidences of new or worsening vertebral fractures and new vertebral fractures were 3.8 and 2.5 %, respectively, in the long-term group. In this group, the BMD continued to increase, and the reduction in BTMs was maintained. In the cross-over group, comparable BMD increases and BTMs reductions to those of in their first year of the long-term group were confirmed. Adverse events did not show a notable increase with long-term denosumab administration. One event of osteonecrosis of the jaw occurred in the cross-over group.

CONCLUSIONS

Three-year denosumab treatment in Japanese subjects with osteoporosis showed a favorable benefit/risk profile.

[Denosumab normalized plasma calcium concentration in malignancy-associated hypercalcaemia]

This case report shows how denosumab apparently treated bisphosphonate-refractory hypercalcaemia caused by a neuroendocrine tumour of the pancreas in a 48-year-old woman. We cannot eliminate the possibility that the patient's DOTATOC-treatment contributed to the decline in plasma calcium concentration. Preliminary results from a recent large, clinical trial, suggest that denosumab is a more potent treatment of malignancy-associated hypercalcaemia than bisphosphonates.