Secondary fracture prevention in Spanish primary care: results of the PREFRAOS Study.

This study demonstrated a large treatment gap in elderly subjects experiencing fragility fracture in Spanish primary care, a low treatment persistence among subjects who do receive treatment, and more than one-quarter having no follow-up visits post-fracture. These data highlight the need to improve secondary fracture prevention in primary care. PURPOSE: To describe osteoporosis (OP) treatment patterns and follow-up in subjects with fragility fracture seen in Spanish primary care (PC). METHODS: This observational, retrospective chart review included subjects aged ≥ 70 years listed in the centers' records (November 2018 to March 2020), with ≥ 1 fragility fracture and prior consultation for any reason; subjects who had participated in another study were excluded. Outcomes included OP treatments and follow-up visits post-fragility fracture. RESULTS: Of 665 subjects included, most (87%) were women; overall mean (SD) age, 82 years. Fewer than two thirds (61%) had received any prior OP treatment (women, 65%; men, 38%); of these, 38% had received > 1 treatment (women, 25%; men, 13%). Among treated subjects, the most frequent first-line treatments were alendronate (43%) and RANKL inhibitor denosumab (22%), with a higher discontinuation rate and shorter treatment duration observed for alendronate (discontinuation, 42% vs 16%; median treatment duration, 2.5 vs 2.1 years). Over one-quarter (26%) of subjects had no follow-up visits post-fragility fracture, with this gap higher in women than men (35% versus 25%). The most common schedule of follow-up visits was yearly (43% of subjects with a fragility fracture), followed by half-yearly (17%) and biennial (10%), with a similar trend in men and women. Most OP treatments were prescribed by PC physicians, other than teriparatide and zoledronate. CONCLUSIONS: Across Spanish PC, we observed a large gap in the treatment and follow-up of elderly subjects experiencing a fragility fracture. Our data highlights the urgent need to improve secondary fracture prevention in PC.

Bone loss after discontinuation of denosumab: the devil is in the details.

A 47-year-old postmenopausal woman with osteoporosis was treated with denosumab, which was discontinued due to side effects. She was therefore transitioned to a yearly intravenous infusion of zoledronic acid. An increase in bone turnover markers together with bone loss at the lumbar spine was observed before the second infusion, suggesting an overshooting of bone resorption due to denosumab discontinuation. On physical examination, the patient was restless and reported having lost about 10 kg since the last visit. A solitary left inferior thyroid nodule was noted on neck palpation. Circulating thyroid hormone levels were elevated, with suppressed thyroid-stimulating hormone. A thyroid scan showed increased uptake in the left inferior nodule with suppression of the remainder of the thyroid gland. A diagnosis of hyperthyroidism due to toxic adenoma was made. The patient was treated with radioactive iodine ablation, with consequent complete normalization of thyroid function. She continued yearly treatment with zoledronic acid. She remained clinically well with no further fractures. Bone turnover markers were appropriately suppressed and bone mineral density increased in the spine and hip. This case illustrates how the overshooting phenomenon following denosumab discontinuation may be compounded by the development of secondary conditions, which can result in suboptimal response to antiresorptive osteoporosis medications.

Sclerotic bone: a sign of bone reaction in patients with medication related osteonecrosis of the jaw.

Medication-related osteonecrosis of the jaw (MRONJ) is a serious adverse reaction associated with antiresorptive drugs such as bisphosphonates and denosumab. When dealing with advanced and/or multiple MRONJ lesions undergoing surgical therapy, the extent of surgery is often a topic of discussion. The aim of this study was to identify the differences in bone density in and around the MRONJ lesion before and after surgical treatment to evaluate the needed surgical extend of the modelling osteotomy. In this retrospective study 26 patients with MRONJ lesions that were surgically treated in our department were observed. Length, width and bone density were measured in panoramic radiograph pre and postoperatively with the Imaging processing software Sidexis and ImageJ (Fiji). The necrotic area, the surrounding sclerotic area as well as the healthy contralateral side were observed. Measurements were performed by two independent observers. Pearson correlation was calculated to determine the interobserver variability. Bone density was significantly reduced in the necrotic bone area compared to the healthy unaffected contralateral reference side. The sclerotic bone area surrounding the necrosis showed increased bone density compared to the contralateral unaffected reference side. The density of the sclerotic bone area was increased in the previously affected MRONJ area in the postoperative panoramic radiograph. The pre and postoperative density showed no significant correlation to healing behaviour. The focus of the modelling osteotomy in surgical treatment of mature MRONJ lesions should be predominantly on the parts that appear necrotic and less dense in the panoramic radiograph as sclerotic areas might be an expression of bone reaction.

Treatment of Osteoporosis in Men on Androgen Deprivation Therapy in Japan.

Background and Objectives: Androgen deprivation therapy (ADT) for prostate cancer has greatly improved treatment outcomes. As patient survival rates have increased, reports of decreased bone density and increased bone fractures as side effects of ADT have emerged. The prevalence of osteoporosis in Japanese men was 4.6%. The purpose of this study was to evaluate the effect of osteoporosis treatment in prostate cancer patients who underwent ADT in Japan. Materials and Methods: The subjects were 33 male patients who had undergone ADT for prostate cancer, who were noted to have decreased bone density. Mean age was 76.2 ± 7.7 years (64-87). Medications included vitamin D in one case, bisphosphonates (BP) in 27 cases, and denosumab in five cases. The evaluation method examined the rate of change in bone mineral density (BMD) before osteoporosis treatment and 1 year after. For comparison, a group without osteoporosis treatment intervention (n = 33) was selected, and matched for prostate cancer treatment and age. The rate of change in trabecular bone score (TBS) was also calculated. Results: The percentage changes in BMD before and 1 year after treatment were as follows: lumbar spine, 7.1 ± 5.8% in the treatment group versus -3.9 ± 4.1% in the no treatment group; femoral neck, 5.5 ± 6.2% in the treatment group versus -0.9 ± 3.9% in the no treatment group; total femur, 6.6 ± 6.4% in the treatment group versus the no treatment group which was -1.7 ± 3.2%. In all cases, there was a clear significant difference (p < 0.01). The percent change in TBS was further calculated in the same manner. There was no significant difference between the two groups: +1.7 ± 3.8% in the treated group versus +0.3 ± 4.1% in the untreated group. Conclusions: Osteoporosis treatment in Japanese patients with prostate cancer on ADT therapy was found to significantly increase BMD compared to the untreated group. BP and denosumab were found to be very effective in increasing BMD.

The Evaluation and Management of Lung Metastases in Patients with Giant Cell Tumors of Bone in the Denosumab Era.

Giant cell tumor of bone (GCTB) is characterized by uncertain biological behavior due to its local aggressiveness and metastasizing potential. In this study, we conducted a meta-analysis of the contemporary literature to evaluate all management strategies for GCTB metastases. A combination of the terms "lung metastases", "giant cell tumor", "bone", "treatment", and "oncologic outcomes" returned 133 patients meeting our inclusion criteria: 64 males and 69 females, with a median age of 28 years (7-63), at the onset of primary GCTB. Lung metastases typically occur at a mean interval of 26 months (range: 0-143 months) after treatment of the primary site, commonly presenting as multiple and bilateral lesions. Various treatment approaches, including surgery, chemotherapy, radiotherapy, and drug administration, were employed, while 35 patients underwent routine monitoring only. Upon a mean follow-up of about 7 years (range: 1-32 years), 90% of patients were found to be alive, while 10% had died. Death occurred in 25% of patients who had chemotherapy, whereas 96% of those not treated or treated with Denosumab alone were alive at a mean follow-up of 6 years (range: 1-19 years). Given the typically favorable prognosis of lung metastases in patients with GCTB, additional interventions beyond a histological diagnosis confirmation may not be needed. Denosumab, by reducing the progression of the disease, can play a pivotal role in averting or delaying lung failure.

Current Concepts in the Treatment of Giant Cell Tumor of Bone: An Update.

Curettage is recommended for the treatment of Campanacci stages 1-2 giant cell tumor of bone (GCTB) in the extremities, pelvis, sacrum, and spine, without preoperative denosumab treatment. In the distal femur, bone chips and plate fixation are utilized to reduce damage to the subchondral bone and prevent pathological fracture, respectively. For local recurrence, re-curettage may be utilized when feasible. En bloc resection is an option for very aggressive Campanacci stage 3 GCTB in the extremities, pelvis, sacrum, and spine, combined with 1-3 doses of preoperative denosumab treatment. Denosumab monotherapy once every 3 months is currently the standard strategy for inoperable patients and those with metastatic GCTB. However, in case of tumor growth, a possible malignant transformation should be considered. Zoledronic acid appears to be as effective as denosumab; nevertheless, it is a more cost-effective option. Therefore, zoledronic acid may be an alternative treatment option, particularly in developing countries. Surgery is the mainstay treatment for malignant GCTB.

Characteristics of isatuximab-derived interference in serum protein electrophoresis and immunofixation, and an absence of sustained in vivo interference due to belantamab mafodotin and denosumab.

OBJECTIVES: Some therapeutic monoclonal antibodies, like daratumumab and elotuzumab, produce interfering monoclonal bands on serum protein electrophoresis (SPEP) and immunofixation electrophoresis (IFE). Whether other common therapeutic antibodies also produce interference has not been systematically evaluated. DESIGN AND METHODS: SPEP/IFE from patients receiving isatuximab (48 patients), belantamab mafodotin (BM; 41), and denosumab (41) were retrospectively reviewed for therapeutic antibody interference. Cases exhibiting isatuximab interference were quantified and the maximum duration of isatuximab effect was evaluated. To characterize band position, neat human serum was spiked with BM or denosumab at supratherapeutic concentrations. Band migration patterns were compared on SPEP and IFE, with band position expressed relative to other constant protein fractions. RESULTS: Isatuximab-induced IFE interference was common (81.3 % of evaluated patients) with a maximum observed duration of 8 weeks. 10.4 % of isatuximab patients had IgG kappa monoclonal gammopathies that co-migrated with the drug; this subset could benefit from HYDRASHIFT 2/4 isatuximab testing. 8.3 % of IFE cases were negative for an isatuximab band but showed large, endogenous M-spikes migrating elsewhere. All patients in this group expired within 1 year of this finding. We hypothesize that an inability to detect isatuximab in this setting corresponds to a large residual myeloma burden that reduces isatuximab serum concentration. This observation may serve as a negative prognostic factor. Spiking studies demonstrated that BM and denosumab produce interference in vitro, but sustained interference was not observed in >40 treated patients. CONCLUSIONS: Therapeutic antibody interference in patients receiving isatuximab is common, and can persist for at least 8 weeks after administration. >10 % of patients receiving isatuximab may benefit from HYDRASHIFT testing post-therapy. In contrast, BM and denosumab fail to produce sustained interference in treated patients.

Denosumab and sclerotherapy for recurrent spinal aneurysmal bone cyst in a child.

Aneurysmal bone cyst (ABC) is a non-malignant, locally destructive, blood-filled lesion in the bone that tends to grow aggressively. A young girl presented with a rapid recurrence after aggressive surgery of a large symptomatic sacral-spinal ABC. After a multidisciplinary tumour board, she was successfully treated with sclerotherapy and monthly intravenous denosumab. The patient has maintained asymptomatic for over 36 months now and has returned to full activity and strength. She never required surgery and has had radiologic resolution of the lesions. Treatment of recurrent ABC requires a multidisciplinary team approach. We believe this to be the first report to use this combined therapy to provide an alternative to morbid surgery for children with ABCs.

Multicentric carpotarsal osteolysis syndrome with variants of MAFB gene: a case report and literature review.

BACKGROUND: Multicentric carpotarsal osteolysis (MCTO) is a rare genetic disorder characterized by the progressive loss of bone in the hands, feet, and other skeletal structures. It presents with symptoms that may resemble those of juvenile idiopathic arthritis, making diagnosis challenging for clinicians. The identification of MAF BZIP Transcription Factor B (MAFB) mutations as significant contributors to MCTO represents a major breakthrough in our understanding of the pathogenesis of this rare skeletal disorder. CASE PRESENTATION: Our objective was to present the phenotype, treatment, and outcome of a patient with a variant of MAFB-induced MCTO to broaden the range of clinical features associated with MCTO and share our clinical experience for improved diagnosis and treatment. In our case, early MRI examination of the bones and whole exome sequencing enabled an early and accurate MCTO diagnosis, and timely Denosumab administration resulted in no deterioration. CONCLUSION: This suggests that MRI examination and whole exome sequencing should be considered when MCTO is suspected, and Denosumab might be an option in the treatment of MCTO.

Cost-Effectiveness Analysis of Denosumab in the Prevention of Skeletal-Related Events Among Patients With Breast Cancer With Bone Metastasis in India.

PURPOSE: Denosumab is clinically superior to zoledronic acid (ZA) for preventing and delaying time to first and subsequent skeletal-related events (SREs) among patients with breast cancer (BC) with bone metastases. We evaluated the cost and health benefits of denosumab and ZA (once every 4 weeks and once every 12 weeks) among four different molecular subtypes of BC with bone metastases in India. MATERIALS AND METHODS: A Markov model was developed in Microsoft Excel to estimate lifetime health consequences and resulting costs among cohort of 1,000 patients with BC with bone metastasis, for three intervention scenarios, namely denosumab (once every 4 weeks), ZA (once every 4 weeks), and ZA (once every 12 weeks). The health outcomes were measured in terms of SREs averted and quality-adjusted life-years (QALYs) gained. The cost of each intervention scenario was measured using both the health system and the patient's perspectives. Indirect costs because of lost productivity were not included. The future costs and outcomes were discounted at the standard rate of 3%. RESULTS: Over a lifetime, the incremental number of SREs averted with use of denosumab once every 4 weeks (compared with ZA once every 4 weeks and once every 12 weeks) among patients with luminal A, luminal B, human epidermal growth factor receptor 2-enriched, and triple negative breast cancer were estimated as 0.39, 0.26, 0.25, and 0.19, respectively. The number of QALYs lived were slightly higher in the denosumab arm (1.45-2.80) compared with ZA once every 4 weeks and once every 12 weeks arms (1.44-2.78). However, denosumab once every 4 weeks was not found to be a cost-effective alternative for either of the four molecular subtypes of breast cancer. ZA once every 12 weeks was found to be a cost-effective option with an average cost-effectiveness ratio ranging between ₹68,254 and ₹73,636. CONCLUSION: ZA once every 12 weeks is the cost-effective treatment option for BC with bone metastases in India. The present study findings hold significance for standard treatment guidelines under India's government-funded health insurance program.

Medication-related osteonecrosis of the jaw in a paediatric patient taking denosumab: a case report.

Medication-related osteonecrosis of the jaw (MRONJ) is a known complication of antiresorptive and anti-angiogenic therapies in adults. Increasingly, these drugs are being prescribed for children with a variety of conditions, such as osteogenesis imperfecta and cancers of the bone. Review of the literature, however, reveals no reported paediatric MRONJ cases to date. We present such a case in a nine-year-old female patient with a vertebral aneurysmal bone cyst, who received dental extractions subsequent to denosumab therapy.

Long-term effects of denosumab on bone mineral density and turnover markers in patients undergoing hemodialysis.

INTRODUCTION: Denosumab, a fully human anti-RANKL monoclonal antibody, is a widely used osteoporosis treatment that is increasingly being used in patients undergoing dialysis; however, its long-term efficacy and safety in these patients remain unknown. MATERIALS AND METHODS: This observational study comprised individuals aged ≥ 20 years undergoing hemodialysis and receiving denosumab. After denosumab administration, we analyzed the long-term changes in bone mineral density (BMD) and levels of bone turnover markers (BTMs) and calcium. RESULTS: The study included 45 patients who have been receiving denosumab for a median duration of 3.8 (interquartile range, 2.5-6.7) years. Tartrate-resistant acid phosphatase 5b (TRACP-5b) levels decreased from a median of 595 (434-778) mU/dL at baseline to 200 (141-430) mU/dL after 6 months of denosumab administration (P < 0.001) and remained low thereafter. Similarly, bone-specific alkaline phosphatase (BAP) levels decreased from a median of 18.2 (15.9-25.8) µg/L at baseline to 12.4 (9.9-15.6) µg/L after 6 months (P < 0.001) and remained low thereafter. Meanwhile, BMD, as assessed with dual energy X-ray absorptiometry and measured at the distal 1/3 of the radius, did not decrease (0.465 ± 0.112 g/cm2 at baseline vs. 0.464 ± 0.112 g/cm2 after administration; P = 0.616). Regarding hypocalcemia, corrected calcium levels reached were the lowest at 7 days after administration and normalized within 30 days. CONCLUSION: The study showed long-term suppression of TRACP-5b and BAP levels and sustaining BMD after denosumab administration over an extended period in patients undergoing hemodialysis.

Assessing EGFR-mutated NSCLC with bone metastasis: Clinical features and optimal treatment strategy.

BACKGROUND: This study aimed to examine the clinical characteristics of bone metastasis (BoM) in patients with non-small cell lung cancer (NSCLC) who have an epidermal growth factor receptor (EGFR) mutation and to identify the most effective treatment strategy using EGFR-tyrosine kinase inhibitors (TKIs). METHODS: The study included patients with stage IV EGFR-mutated NSCLC who were receiving first-line treatment with EGFR-TKIs between January 2014 and December 2020. These patients were divided into two groups based on the presence or absence of BoM at the time of initial diagnosis. The BoM group was further subdivided based on whether they received denosumab or not. RESULTS: The final analysis included 247 patients. Those with BoM at initial diagnosis had shorter progression-free survival (12.6 vs. 10.5 months, p = 0.002) and overall survival (OS) (49.7 vs. 30.9 months, p = 0.002) compared to those without BoM. There was a difference in the location of metastatic sites between the two groups, with a higher incidence of extrathoracic metastasis in the BoM group (p < 0.001). The incidence of T790M was higher in patients with BoM than in those without (47.4% vs. 33.9%, p = 0.042). Multivariate Cox regression analysis revealed that sequential osimertinib treatment and the addition of antiangiogenic therapy (AAT) and denosumab therapy improved OS in patients with BoM. CONCLUSIONS: The presence of BoM is a negative prognostic factor for NSCLC patients with an EGFR mutation, possibly due to the presence of extrathoracic metastases. However, adding AAT and denosumab, along with sequential osimertinib, to the treatment regimen for patients with BoM can improve survival outcomes.

Treatment of bone metastases from solid tumors with bone-modifying agents: a web survey of Italian oncologists investigating patterns of practice drug prescription and prevention of side effects.

PURPOSE: Optimal use of bone-modifying agents (BMAs) in patients with bone metastases from solid tumors is uncertain in some aspects: the drug choice; the planned treatment duration and long-term therapy; the prevention and management of possible side effects, including renal toxicity, hypocalcaemia, and medication-related osteonecrosis of the jaw (MRONJ). METHODS: Italian oncologists were invited to fulfil a 24-question web survey about prescription of BMAs for bone metastases of breast cancer, prostate cancer, and other solid tumors. Prevention and management of side effects were also investigated. RESULTS: Answers of 191 oncologists were collected. BMAs are usually prescribed at the time of diagnosis of bone metastases by 87.0% (breast cancer) and 76.1% (solid tumors except breast and prostate cancers) of oncologists; the decision is more articulated for prostate cancer (endocrine-sensitive versus castration-resistant). The creatinine level (32.3%), the availability of patient venous access (15.8%), and the type of primary neoplasm (13.6%) are the most reported factors involved in choice between bisphosphonates and denosumab. Zoledronic acid every 3 months was considered as a valid alternative to monthly administration by 94% of Italian oncologists. Oncologists reported a good confidence with measures aimed to prevent MRONJ, whereas uncertainness about prevention and management of hypocalcemia was registered. CONCLUSION: Italian oncologists showed a high attitude in prescribing bisphosphonates or denosumab at the time of diagnosis of bone metastases, with a large application of preventive measures of side effects. Further studies are needed to investigate some controversial aspects, such as optimal drug treatment duration and long-term drug schedules.

The RANKL inhibitor denosumab in combination with dual checkpoint inhibition is associated with increased CXCL-13 serum concentrations.

BACKGROUND: Recent evidence suggests additional immunomodulatory properties of RANKL inhibition possibly boosting the clinical efficacy of immune checkpoint inhibitors (ICI). METHODS: We conducted a prospective, multicentre clinical trial in unresectable stage IV melanoma patients with bone metastases who received denosumab in parallel with dual ICI (BONEMET) and performed comprehensive immune monitoring at baseline and 4, 12, and 24 weeks after initiation of therapy. Secondary endpoints included tolerability and efficacy. For comparison, biospecimens from melanoma patients treated with dual ICI without denosumab were analyzed accordingly and served as retrospective reference cohort. RESULTS: In both the BONEMET (n = 16) and the reference cohort (n = 18) serum levels of 17 cytokines, including IFNγ were significantly increased after 4 weeks of treatment. Patients who received ICI and denosumab showed a significantly higher increase in serum CXCL-13 and a significant decrease in VEGFc compared with the reference cohort. While no changes in T cell composition were observed at 4 weeks, patients in the BONEMET cohort showed a significant decrease in the peripheral naïve T-cell population and an increase in CD8+ effector cells after 12 weeks. Treatment-related adverse events occurred with comparable frequency (93.8% in the BONEMET cohort versus 83.3% in the reference cohort). 7/16 patients in the BONEMET cohort and 8/18 patients in the reference cohort achieved disease control. CONCLUSION: Denosumab in combination with dual ICI modulates cytokine expression and T-cell composition in peripheral blood. The upregulation of CXCL-13, a key factor for initiating tertiary lymphoid structures, strengthens the hypothesis that denosumab indeed boost immunological effects.

Association between pharmacotherapy and secondary vertebral fracture managed with a brace in a real-world setting: A nationwide database study in Japan.

AIM: This retrospective cohort study assessed the association between the incidence of secondary vertebral fracture managed with a brace (SVF) and pharmacotherapy. METHODS: The association between the incidence of SVF and the presence, type, and medication possession ratio (MPR) of pharmacotherapy was investigated using medical insurance data acquired from the National Database of Health Insurance Claims and Specific Health Checkups of Japan. RESULTS: The data of female patients (n = 637 303) were analyzed. The 2-year incidence of SVF was 73.5 per 10 000 patients (n = 4687). Approximately 0.73% of patients without medications and 0.74% with medications had SVF. Patients taking bisphosphonates (0.87), denosumab (0.77), and selective estrogen receptor modulators (0.88) had significantly lower standardized incidence ratios (SIRs) than patients not taking medications after the occurrence of primary fracture; meanwhile, patients taking parathyroid hormone medications had considerably higher SIRs than those not taking medications. The non-SVF group (59.1%) had a significantly higher mean MPR than the SVF group (55.5%). Patients taking denosumab in the non-SVF group (68.2%) had the highest mean MPR. The proportion of patients taking denosumab with an MPR of ≥80% in the non-SVF group was significantly higher than that in the SVF group. CONCLUSION: Patients taking medications were at a lower risk of developing SVF than those not taking medications. Although this study did not compare the medications' SVF prevention effects, patients taking denosumab had a 0.77 SIR of SVF in Japan. The effect of pharmacotherapy on SVF prevention might be affected by the MPR of each medication. Geriatr Gerontol Int 2024; 24: 390-397.

Recurrent severe hypocalcemia following chemotherapy regimen changes in advanced breast cancer: two case reports.

BACKGROUND: As an oncologic emergency related to abnormalities in calcium metabolism, hypercalcemia associated with paraneoplastic syndrome and bone metastases is well known. Meanwhile, the incidence of hypocalcemia is low, except in cases associated with bone-modifying agents used for bone metastases. Hypocalcemia induced by bone-modifying agents typically occurs early after the initial administration, and its incidence can be significantly reduced by preventive administration of calcium and vitamin D3 supplements. CASE REPORT: We report two cases of recurrent severe hypocalcemia occurring during chemotherapy for metastatic breast cancer with multiple bone metastases. Case 1: A 35-year-old Japanese woman developed metastases in the bone, liver, and ovaries during postoperative endocrine therapy for invasive lobular carcinoma of the breast. She underwent chemotherapy and treatment with denosumab. She experienced recurrent episodes of severe hypocalcemia subsequent to a change in the chemotherapy regimen. Case 2: A 65-year-old Japanese woman encountered multiple bone metastases after postoperative anti-human epidermal growth factor receptor 2 therapy and during endocrine therapy for invasive ductal carcinoma of the breast. She underwent anti-human epidermal growth factor receptor 2 therapy and treatment with denosumab. She experienced recurrent severe hypocalcemia subsequent to a change in the chemotherapy regimen to letrozole + lapatinib, trastuzumab emtansine, and lapatinib + capecitabine. CONCLUSIONS: We observed two cases of recurrent severe hypocalcemia in patients with advanced breast cancer and bone metastases after modifications to their therapy regimens. These cases differed from the typical hypocalcemia induced by bone-modifying agents. It is possible that antitumor drugs affect calcium and bone metabolism associated with bone metastases. While these cases are rare, it is crucial for oncologists to be aware of hypocalcemia not only at the initiation of bone-modifying agents but also throughout the entire antitumor therapy, as hypocalcemia can lead to fatal outcomes.

Effect of denosumab on inflammation and bone health in active Charcot foot: A phase II randomised controlled trial.

AIMS: We aimed to investigate the effect of denosumab on pedal bone health and clinical resolution in active Charcot foot (CN). METHODS: This multicentre open-label phase 2 randomised controlled trial recruited adults with diabetes mellitus and active CN within 3 months of onset. Participants were randomised to standard care alone, or with denosumab 60 mg subcutaneously. Denosumab was administered at baseline and again at 6 months, unless foot temperature had normalised (i.e. <2 °C compared to contralateral foot). Co-primary outcomes were change in calcaneal Stiffness Index and foot temperature normalisation over 18 months. RESULTS: Twelve participants per group were analysed; mean age 58 ± 11 years, 83 % male and 92 % had type 2 diabetes. Active CN duration was median 8 (IQR 7-12) weeks. Ninety-two percent were Eichenholtz stage 1 and 96 % involved the midfoot. After 1-month, median decline in Stiffness Index was less in the denosumab verses standard care group (0.5 [IQR -1.0 to 3.9] vs -2.8 [-8.5 to -1.0], p = 0.008). At 18-months, 92 % of the denosumab group attained foot temperature normalisation versus 67 % of the standard care group (p = 0.13). CONCLUSIONS: Denosumab ameliorated the early decline in calcaneal Stiffness Index associated with active CN. However, no difference in normalisation of foot temperature was observed.

Temporal patterns of osteoclast formation and activity following withdrawal of RANKL inhibition.

Rebound bone loss following denosumab discontinuation is an important clinical challenge. Current treatment strategies to prevent this fail to suppress the rise and overshoot in osteoclast-mediated bone resorption. In this study, we use a murine model of denosumab treatment and discontinuation to show the temporal changes in osteoclast formation and activity during RANKL inhibition and withdrawal. We show that the cellular processes that drive the formation of osteoclasts and subsequent bone resorption following withdrawal of RANKL inhibition precede the rebound bone loss. Furthermore, a rise in serum TRAP and RANKL levels is detected before markers of bone turnover used in current clinical practice. These mechanistic advances may provide insight into a more defined window of opportunity to intervene with sequential therapy following denosumab discontinuation.

Stopping denosumab, a medication commonly used to improve bone mass by blocking formation of bone resorbing osteoclasts, leads to a rebound loss in the bone which was gained during treatment. Current strategies to prevent this bone loss fail in most cases as they are unable to prevent the rise and overshoot in bone resorption by osteoclasts. Thie stems from an incomplete understanding of how osteoclasts behave during denosumab treatment and after treatment is discontinued. We use a mouse model of this phenomenon to show how osteoclast formation and activity changes throughout this process. We show that increases in the processes that drive the formation of osteoclasts can be detected in the circulation before bone loss occurs. These findings could therefore provide insight into a targeted 'window of opportunity' to intervene and prevent the rebound bone loss following stopping denosumab in patients.

Equivalence trial of proposed denosumab biosimilar GP2411 and reference denosumab in postmenopausal osteoporosis: the ROSALIA study.

Denosumab is a monoclonal antibody used to reduce risk of fractures in osteoporosis. ROSALIA was a multicenter, double-blind, randomized, integrated phase I/phase III study comparing the efficacy, pharmacokinetics (PK), pharmacodynamics (PD), immunogenicity, and safety of proposed biosimilar denosumab GP2411 with reference denosumab (REF-DMAb) (Prolia®; Amgen). Postmenopausal women with osteoporosis were randomized 1:1 to 2 60-mg doses of GP2411 or REF-DMAb, one at study start and one at week 26. At week 52, the REF-DMAb group was re-randomized 1:1 to a third dose of REF-DMAb or switch to GP2411. The primary efficacy endpoint was percentage change from baseline (%CfB) in LS-BMD at week 52. Secondary efficacy endpoints were %CfB in LS-BMD, FN-BMD, and TH-BMD at weeks 26 and 78 (and week 52 for FN-BMD and TH-BMD). Primary PK and PD endpoints were the area under the serum concentration-time curve extrapolated to infinity and maximum drug serum concentration at week 26, and the area under the effect-time curve of the %CfB in serum CTX at week 26. Secondary PK and PD endpoints included drug serum concentrations and %CfB in serum CTX and P1NP during the study period. Similar efficacy was demonstrated at week 52, with 95% CIs of the difference in %CfB in LS-BMD between treatment groups fully contained within prespecified equivalence margins. Similarity in PK and PD was demonstrated at week 26. Immunogenicity was similar between groups and was not impacted by treatment switch. The rate of new vertebral fractures was comparable. Treatment-emergent adverse events were comparable between groups (63.6% [GP2411/GP2411]; 76.0% [REF-DMAb/REF-DMAb]; 76.6% [REF-DMAb/GP2411]). In conclusion, ROSALIA showed similar efficacy, PK and PD, and comparable safety and immunogenicity of GP2411 to REF-DMAb in postmenopausal osteoporosis.

Denosumab is a biologic treatment that stops bone breakdown. This clinical trial evaluated how similar GP2411 (a denosumab biosimilar in development) is compared with European-approved reference denosumab in women with post-menopausal osteoporosis. Biosimilars are highly similar to the original treatment ('reference denosumab') and may have a lower price. 263 patients were randomly assigned to receive GP2411 and 264 to reference denosumab. Treatment was given at the study beginning, at Week 26 and at Week 52. 124 patients were re-assigned at Week 52 to test the effect of changing from reference denosumab to GP2411. The study showed similarity in how the body interacts with the treatments, what effects the treatment has (both measured over 26 weeks), and bone mineral density (measured over 78 weeks). Antibody responses to GP2411 were detected in similar proportions of patients on each treatment. Reported adverse events were similar between treatments before Week 52, and from Week 52 to 78, and <5% of patients experienced serious adverse events. A change of treatment from reference denosumab to GP2411 did not affect outcomes. These results showed similarity between GP2411 and reference denosumab in this population. In future, GP2411 may enable more patients to benefit from denosumab.