Changes in RANKL and TRAcP 5b after discontinuation of denosumab suggest RANKL mediated formation of osteoclasts results in the increased bone resorption.

In patients discontinuing long-term denosumab, RANKL levels are high 6 months after the last denosumab injection. Nine and 12 months after the last denosumab injection RANKL levels are lower, but TRAcP 5b levels are higher, suggesting that accumulated RANKL increases the number of active osteoclasts. PURPOSE: The rapid increase in bone turnover occurring when discontinuing long-term treatment with denosumab (DMAB), an antibody that neutralizes receptor activator of nuclear factor kappa-B ligand (RANKL) is not fully understood. We aimed to investigate the mechanisms underlying the rebound activation of bone resorption by measuring tartrate-resistant acid phosphatase 5b (TRAcP 5b), RANKL, osteoprotegerin (OPG), C-terminal collagen crosslinks (CTX), and procollagen type I N-propeptide (P1NP) in patients discontinuing long-term DMAB. METHODS: Sixty-one patients with BMD T-score > - 2.5 at the spine and hip discontinuing long-term DMAB were randomized to treatment with zoledronate (ZOL) 6 months (6 M group, n = 20), 9 months (9 M group, n = 20) or 12 months after the last DMAB injection or when bone turnover was high (12 M group, n = 21). Bone turnover markers were measured immediately before initiation of ZOL treatment. RESULTS: We found higher CTX and PINP in the 9 M and 12 M groups compared to the 6 M group (p < 0.001). In the 6 M group, TRAcP 5b was lower and RANKL higher than in the other two groups (p < 0.001). TRAcP 5b correlated negatively with RANKL (R = - 0.54), and time since the last DMAB injection correlated positively with CTX (R = 0.56), PINP (R = 0.72), TRAcP 5b (R = 0.51) and negatively with RANKL (R = - 0.70) (p < 0.001 for all). We found no difference in OPG between groups. CONCLUSION: Following discontinuation of long-term DMAB, we find high levels of RANKL, which most likely result in an increase in the number of active osteoclasts (illustrated by TRAcP5b) causing an increased bone turnover.

Discontinuation of denosumab in men with prostate cancer.

In patients with non-metastatic prostate cancer, treated with radiation therapy and androgen deprivation therapy for 3 years and DMAB on average for 5 years, BMD was in the normal or osteopenic range. Discontinuation of DMAB led to a bone loss of 2-5%. In men with osteopenia, the bone loss was prevented by zoledronate. PURPOSE: Patients with prostate cancer receiving androgen deprivation therapy (ADT) are treated with denosumab (DMAB) to prevent fractures and preserve bone mass. We wanted to investigate the change in BMD in men with non-metastatic prostate cancer discontinuing DMAB. METHODS: We conducted a retrospective cohort study based on medical records from patients referred to the Department of Endocrinology from the Department of Urology, Aarhus University Hospital between June 1, 2018, and June 1, 2021. We retrieved information on biochemistry and DXA performed 0-6 months after the last DMAB injection and a second DXA performed approximately 12 months after the first. In case of a BMD T-score ≤ - 1 at the lumbar spine or total hip at the first DXA, the patients were treated with zoledronate. The primary endpoint was change in lumbar spine BMD. RESULTS: We included 50 patients with non-metastatic prostate cancer. The mean DMAB treatment duration was 5 ± 0.1 years. Among the patients treated with zoledronate (n = 9), BMD was maintained at the spine and femoral neck after a mean of 16 months. We found a significant decrease in BMD; - 4.9 ± 4.2%, - 1.9 ± 3.5%, and - 2.4 ± 3.6% at the spine, total hip, and femoral neck between the first and second DXA in the patients not treated with zoledronate (n = 24) (p ≤ 0.01 for all). One patient who did not receive ZOL sustained multiple fragility vertebral fractures after DMAB discontinuation. CONCLUSION: In men with non-metastatic prostate cancer, discontinuation of DMAB after stopping ADT led to an average bone loss of 2-5%. Zoledronate prevented bone loss in men with osteopenia.

Denosumab Discontinuation.

PURPOSE OF REVIEW: To review the pathophysiology, the clinical consequences as well as way of mitigating the effects of denosumab discontinuation. RECENT FINDINGS: Treatment with denosumab (DMAB) is reversible and upon discontinuation there is a rapid increase in bone turnover and a subsequent bone loss. During this phase of high bone turnover, an increased risk of fractures has been reported. Therefore, treatment with DMAB could be considered life-long. However, side-effects may prompt the need for discontinuation and moreover, treatment with DMAB may have increased BMD to levels where continuing treatment does not provide further fracture risk reduction. Patients stopping DMAB should be offered subsequent antiresorptive treatment with an intense monitoring regimen during the initial year as most of the bone loss occurs within these initial 12 months. In this review, we evaluated the literature published over the past 1 to 3 years investigating DMAB withdrawal with focus on bone turnover markers, bone mineral density, and fracture risk and the transition to other anti-osteoporosis therapies. Furthermore, we summarized the current recommendations of international guidelines. In this review, we evaluated the literature published over the past 1 to 3 years investigating denosumab (DMAB) discontinuation and the transition to other anti-osteoporosis therapies. Additionally, we summarized the current recommendations of international guidelines.

The interplay between HPV and host immunity in head and neck squamous cell carcinoma.

Persistent infection with human papillomavirus (HPV) type 16 is a major risk factor for the development of head and neck squamous cell carcinoma (HNSCC), in particular oropharyngeal squamous cell carcinoma (OPSCC). The oropharyngeal epithelium differs from the mucosal epithelium at other commonly HPV16-infected sites (i.e., cervix and anogenital region) in that it is juxtaposed with the underlying lymphatic tissue, serving a key immunologic function in the surveillance of inhaled and ingested pathogens. Therefore, the natural history of infection and immune response to HPV at this site may differ from that at other anatomic locations. This review summarizes the literature concerning the adaptive immune response against HPV in the context of HNSCC, with a focus on the T-cell response. Recent studies have shown that a broad repertoire of tumor-infiltrating HPV-specific T-cells are found in nearly all patients with HPV-positive tumors. A systemic response is found in only a proportion of these. Furthermore, the local response is more frequent in OPSCC patients than in cervical cancer patients and HPV-negative OPSCC patients. Despite this, tumor persistence may be facilitated by abnormalities in antigen processing, a skewed T-helper cell response, and an increased local prevalence of T-regulatory cells. Nonetheless, the immunologic profile of HPV-positive vs. HPV-negative HNSCC is associated with a significantly better outcome, and the HPV-specific immune response is suggested to play a role in the significantly better response to therapy of HPV-positive patients. Immunoprofiling may prove a valuable prognostic tool, and immunotherapy trials targeting HPV are underway, providing hope for decreasing treatment-related toxicity.

Treatment With Zoledronate Subsequent to Denosumab in Osteoporosis: A 2-Year Randomized Study.

Increased bone turnover and rapid bone loss follow discontinuation of denosumab. We investigated the long-term efficacy of zoledronate (ZOL) in maintaining bone mineral density (BMD) after discontinuation of denosumab. In this randomized, open-label, interventional study, we included 61 postmenopausal women and men older than 50 years discontinuing denosumab after 4.6 ± 1.6 years. We administered ZOL 6 months (6 M) or 9 months (9 M) after the last denosumab or when bone turnover had increased (observation group [OBS]). ZOL was readministrated if p-cross-linked C-terminal telopeptide (p-CTX) increased ≥1.26 µg/L or BMD decreased ≥5%. The results after 12 months have previously been published; here we report the outcome after 24 months (ClinicalTrials NCT03087851). Fifty-eight patients completed the study. From 12 to 24 months after the initial ZOL, lumbar spine (LS) BMD was maintained: 0.9 ± 0.9%, 0.4 ± 0.8%, and 0.3 ± 0.7% in the 6 M, 9 M, and OBS groups, respectively (p > .05, no between-group differences). Similarly, total hip (TH) and femoral neck (FN) BMD did not change in any group during year 2. From baseline to 24 months after ZOL, LS BMD decreased by 4.0 ± 0.8%, 4.1 ± 0.8%, and 4.3 ± 1.5% in the 6 M, 9 M, and OBS groups, respectively (p < .001, no between-group differences). Significant bone loss (LS, TH, or FN) was found in all groups 24 months after ZOL: 6 M group: n = 12 (60%), 9 M group: n = 7 (37%), and OBS group: n = 10 (53%). P-CTX did not change significantly during the second year (p > .05, no between-group differences). No patient fulfilled the CTX or fracture criteria for retreatment during year 2; however, 9 patients were retreated at M24 due to BMD loss ≥5%. Two patients sustained a non-vertebral fracture during year 2. Treatment with ZOL subsequent to long-term denosumab did not fully prevent increased bone turnover and bone loss during the first year; however, CTX remained with the reference range and BMD was maintained during the second year. © 2021 American Society for Bone and Mineral Research (ASBMR).

Treatment with Zoledronate Subsequent to Denosumab in Osteoporosis: a Randomized Trial.

Discontinuing denosumab is associated with bone loss and possibly increased fracture risk. We investigated if treatment with zoledronate (ZOL) could prevent bone loss and if the timing of the ZOL infusion influenced the outcome. We report on a 2-year randomized, open label, interventional study including 61 patients with osteopenia, discontinuing denosumab after 4.6 ± 1.6 years. We administrated ZOL 6 months (6M group, n = 20) or 9 months (9M group, n = 20) after the last denosumab injection or when bone turnover had increased (OBS group, n = 21). We monitored the patients with DXA and bone turnover markers. Our primary endpoints were change in lumbar spine BMD (LSBMD) 6 months after ZOL and the proportion of patients who failed to maintain BMD. The study is ongoing (clinicaltrials.gov; NCT03087851). We included 61 participants and 59 patients completed follow-up 12 months after ZOL. Six months after ZOL, LSBMD had decreased significantly by (mean ± SE) 2.1% ± 0.9%, 4.3% ± 1.1%, and 3.0% ± 1.1% in the 6M, 9M, and OBS groups, respectively, and by 4.8% ± 0.7%, 4.1% ± 1.1%, and 4.7% ± 1.2% 12 months after ZOL in the 6M, 9M, and OBS groups, respectively (p < .02, no between-group differences). BMD loss above the least significant change was seen in all groups; at the spine: 6M, n = 6 (30%); 9M, n = 9 (45%); and OBS, n = 9 (47%); and at the total hip: 6M, n = 1 (5%); 9M, n = 5 (25%); and OBS, n = 2 (11%). In the 6M group p-crosslinked C-terminal telopeptide (p-CTX) decreased initially, but increased rapidly thereafter, and 6 months after ZOL, p-CTX was 0.60 ± 0.08 g/L. p-CTX increased rapidly in the 9M and OBS groups, was suppressed by ZOL but increased again thereafter; p-CTX was 0.47 ± 0.05 µg/L and 0.47 ± 0.05 µg/L in the 9M and OBS groups 6 months after ZOL, respectively. Incident vertebral fractures were seen in two women in the 9M group. Treatment with ZOL irrespective of the timing did not fully prevent loss of BMD in patients discontinuing denosumab. © 2020 American Society for Bone and Mineral Research.

Current Status of Bone-Forming Therapies for the Management of Osteoporosis.

In patients with osteoporosis and severely reduced bone mass and/or recurring fractures, antiresorptive therapy may not be the optimal first-line treatment. Two recent clinical trials comparing bone-forming treatment with antiresorptive therapy have demonstrated that bone-forming treatment is superior in reducing the fracture risk in patients with severe osteoporosis. All of the currently available bone-forming agents-teriparatide, abaloparatide, and romosozumab-increase bone mineral density (BMD) and reduce the fracture risk; however, the effect wears off with time and treatment is therefore only transient. Thus, a bone-forming therapy should be followed by antiresorptive treatment with a bisphosphonate or denosumab. The BMD response to bone-forming treatment is reduced in patients previously treated with antiresorptive drugs; however, based on the findings of the VERO trial, the anti-fracture efficacy of bone-forming treatment in comparison with antiresorptives seems to be preserved. This review provides an overview of the existing bone-forming therapies for osteoporosis including considerations of sequential and combination therapy.

The clinical potential of romosozumab for the prevention of fractures in postmenopausal women with osteoporosis.

The glycoprotein sclerostin inhibits activation of the canonical Wnt pathway and thereby suppresses bone formation by inhibiting the osteoblasts. Additionally, sclerostin increases bone resorption by stimulating the production of receptor activator of nuclear factor kappa-ß-ligand (RANKL). Romosozumab (ROMO) is a monoclonal antibody against sclerostin. Phase III clinical trials in postmenopausal women with osteoporosis have shown that ROMO increases bone mineral density at the lumbar spine and hip and reduces the risk of vertebral and clinical fractures in comparison with placebo. In women with severe osteoporosis, ROMO reduces the risk of vertebral, nonvertebral and clinical fractures in comparison with alendronate. ROMO is the first treatment for osteoporosis with dual action, and may become a valuable tool for improving the treatment of osteoporosis. At present, the approval of ROMO by the authorities is awaiting further investigations of a potential increased risk of cardiovascular events associated with ROMO treatment.

Non-parathyroid hypercalcemia associated with paraffin oil injection in 12 younger male bodybuilders: a case series.

INTRODUCTION: Injection of paraffin oil to augment muscles size is a troubling phenomenon known to cause a foreign body reaction with formation of granulomas. In a few case reports, long-term side effects have been reported in terms of hypercalcemia and renal failure. METHODS: We identified a case series of 12 male bodybuilders presenting with non-parathyroid hypercalcemia who previously had injected paraffin oil to increase muscles size. RESULTS: At admission, all patients had moderate-to-severe hypercalcemia with suppressed PTH levels and impaired renal function. Calcitriol levels were within the normal range or slightly elevated. Follow-up measurements showed marked hypercalciuria with nearly normal levels of bone turnover markers. A correlation was found between levels of peptidyl dipeptidase and calcitriol (R = 0.812, P = 0.050). Treatment with antiresorptive agents seemed less effective than glucocorticoids, which resulted in a significantly lowering of ionized calcium levels and improved renal function, although no patients were cured by this treatment. Immunosuppression with azathioprine or mycophenolate may have a glucocorticoid-saving effect. One patient had surgery with removal of affected muscle tissue, without any apparent effect on plasma calcium levels. CONCLUSION: The hypercalcemia and associated hypercalciuria seems to be due to an intestinal hyperabsorption of calcium. It remains to be elucidated, whether an increased calcitriol synthesis within granulomas is the only (main) mechanism by which intestinal calcium absorption is increased. Glucocorticoids seem most appropriate as the first choice for treatment. Bodybuilders should be warned against use of intramuscular oil injections (and other substances), as this may have severe adverse health consequences.