Romosozumab and cardiovascular safety in Japan

Treatment effects, adverse outcomes and cardiovascular safety of romosozumab - Existing worldwide data: A systematic review and meta-analysis

Background

Romosozumab is a novel monoclonal antibody that binds to sclerostin, and has dual effects of increasing bone formation and decreasing bone resorption, giving it a unique mechanism of action. The objective of this study was to perform a systematic review and meta-analysis based on existing worldwide data on treatment effects and safety of romosozumab in randomized controlled trials.

Methods

A systematic search was carried out on four databases including PubMed, Embase, Web of Science and Cochrane Central Register of Controlled Trials (CENTRAL). The keywords used for search was "(romosozumab) AND (osteoporosis OR safety)". Randomized controlled trial or post-hoc studies of the included randomized controlled trial which studied the effects and safety of romosozumab were included. The quality of selected studies was assessed with the Cochrane collaboration tool and the PEDro scale.

Results

20 studies were included for qualitative analysis. 14 studies were included for meta-analysis. In total, there were 13,507 (n = 13,507) participants with 637 men and 12,870 women from original cohorts. The overall mean difference was in favor of romosozumab treatment for lumbar spine (10.04 (95 % confidence interval (CI) = 7.51-12.57; p < 0.00001)), total hip (4.04 (95 % CI = 3.10-4.99; p < 0.00001)) and femoral neck bone mineral density (3.77 (95 % CI = 2.90-4.64; p < 0.00001)) at 12 months. There was significantly less likelihood of new vertebral fractures with romosozumab compared to control (odds ratio (OR) 0.42 (95 % CI = 0.20-0.89); p = 0.02) at 12 months of treatment. There was significantly less likelihood of new vertebral fracture at 24 months with 12 months of romosozumab followed by sequential treatment with anti-resorptive compared to control with only anti-resorptive agent use (OR 0.36 (95 % CI = 0.18-0.71); p = 0.003). There was no significant difference in serious adverse events and fatal adverse events with use of romosozumab compared with control in our meta-analyses. There were no significant differences in serious cardiovascular events in Asian population of romosozumab with control group with 12 months of romosozumab treatment followed by 24 months of anti-resorptive agent with OR 1.09 (95 % CI = 0.40-2.96; P = 0.86). There was no significant difference between romosozumab group and control group for the median time to radiographic healing. Our qualitative analysis on Quantitative Computed Tomography (QCT), Finite element analysis (FEA) and bone biopsy analyses demonstrated that romosozumab improved parameters and measures in these domains as well.

Conclusion

In conclusion, our study showed that romosozumab was an effective agent to treat osteoporosis with high quality evidence. There were no significant differences in the adverse events, serious adverse events, fatal adverse events identified. Further subgroup analysis of cardiovascular events and cardiovascular death in the total population showed no differences either.

The translational potential of this article

Given the results, romosozumab is an effective agent to treat patients with very-high risk of osteoporotic fractures.

Drug utilization pattern of romosozumab and other osteoporosis treatments in Japan, 2019-2021

INTRODUCTION

Describe real-world treatment of osteoporosis and romosozumab treatment patterns in Japan.

MATERIALS AND METHODS

Data for patients initiating romosozumab or other antiosteoporotic medications between March 01, 2018, and May 31, 2022, were extracted from the Medical Data Vision (MDV) and Japan Medical Data Center (JMDC) databases. Patients were categorized into four cohorts: those who newly initiated romosozumab within the first (MDV: n = 4782; JMDC: n = 2578) or second (MDV: n = 3888; JMDC: n = 2446) year after launch and those who initiated teriparatide (TPTD; MDV: n = 14,576; JMDC: n = 8259) or non-TPTD antiosteoporotic medications within the first year of romosozumab launch (MDV: n = 352,142; JMDC: n = 185,785).

RESULTS

Mean age, sex, baseline cardiovascular history, comorbidities, and concomitant medications were similar across cohorts. In the MDV database, fracture history was higher in the romosozumab year-1 (59.3%), year-2 (64.1%), and TPTD (65.5%) cohorts versus the non-TPTD cohort (24.4%). Similar rates were identified in the JMDC database: romosozumab year-1 (64.7%), year-2 (66.6%), TPTD (67.5%), and non-TPTD (27.8%). Vertebral fractures were most common in all cohorts. 12-month romosozumab discontinuation varied between the year-1 and year-2 cohorts in MDV (62.4% and 58.8%) and JMDC (57.1% and 52.7%), whereas mean number of injections remained consistent (MDV: 9.7 and 9.8; JMDC: 7.3 and 7.8). Romosozumab persistence was lower in year-1 versus year-2 (MDV: 37.6% and 42.9%; JMDC: 41.2% and 47.3%).

CONCLUSION

Patients initiating romosozumab and TPTD had a high fracture history. Given the dual effects of promoting bone formation and suppressing resorption, improving romosozumab adherence and persistence over time may be important for antiosteoporotic therapy.

Discovery of the small molecular inhibitors against sclerostin loop3 as potential anti-osteoporosis agents by structural based virtual screening and molecular design

Sclerostin is a secreted glycoprotein that expresses predominantly in osteocytes and inhibits bone formation by antagonizing the Wnt/β-catenin signaling pathway, and the loop3 region of sclerostin has recently discovered as a novel therapeutic target for bone anabolic treatment without increasing cardiovascular risk. Herein, we used a structural based virtual screening to search for small molecular inhibitors selectively targeting sclerostin loop3. A novel natural product hit ZINC4228235 (THFA) was identified as the sclerostin loop3-selective inhibitor with a Kd value of 42.43 nM against sclerostin loop3. The simplification and derivation of THFA using molecular modeling-guided modification allowed the discovery of an effective and loop3-selective small molecular inhibitor, compound (4-(3-acetamidoprop-1-yn-1-yl)benzoyl)glycine (AACA), with improved binding affinity (Kd = 15.4 nM) compared to the hit THFA. Further in-vitro experiment revealed that compound AACA could attenuate the suppressive effect of transfected sclerostin on Wnt signaling and bone formation. These results make AACA as a potential candidate for development of anti-osteoporosis agents without increasing cardiovascular risk.

[Osteoporosis treatment for fracture prevention in elderly]

Fracture prevention in the elderly is an urgent issue at all levels: individual, family, and societal. Osteoporosis is the underlying cause of fractures in the elderly, and it is important to understand its pathogenesis and treatment. Diet, exercise, and pharmacotherapy are all important for fracture prevention. Particularly with regard to pharmacotherapy, it is important to understand the mechanism of action of each drug and its characteristics and problems from a clinical point of view. Appropriate treatment of osteoporosis has been proven to reduce fractures in the elderly, and its widespread implementation is desirable.

Sclerostin and Cardiovascular Disease

PURPOSE OF REVIEW

The role of wnt signalling in atherogenesis raises the possibility that the wnt inhibitor, sclerostin, provides a natural defence to this process, and that anti-sclerostin antibodies might increase the risk of atherosclerosis and associated conditions such as CVD. This article aims to triangulate evidence concerning possible adverse effects of sclerostin inhibition on CVD risk.

RECENT FINDINGS

Randomised controlled trials of treatment with the anti-sclerostin antibody, romosozumab, have yielded conflicting evidence with respect to possible adverse effects of sclerostin inhibition on CVD risk. To further examine the causal relationship between sclerostin inhibition and CVD risk, three Mendelian randomisation (MR) studies have examined effects of sclerostin lowering on CVD outcomes, using common genetic variants in the SOST gene which produces sclerostin, to mimic effects of a randomised trial. Concordant findings were seen in two studies, comprising an effect of sclerostin lowering on increased risk of MI and type II diabetes mellitus. One study also suggested that sclerostin lowering increases coronary artery calcification. Triangulation of evidence from different sources provides some suggestion that sclerostin lowering increases MI risk, supporting the need for CVD risk assessment when considering treatment with romosozumab.

Role of Sclerostin in Cardiovascular Disease

Sclerostin is most recognized for its role in controlling bone formation but is also expressed in the heart, aorta, coronary, and peripheral arteries. This review summarizes research on sclerostin's role in cardiovascular disease. Rodent studies have found sclerostin to be expressed at sites of arterial calcification. In contrast, aortic sclerostin was reported to be downregulated in a mouse model of abdominal aortic aneurysm, and transgenic upregulation or administration of sclerostin was found to prevent abdominal aortic aneurysm and atherosclerosis formation. Sclerostin deficiency was reported to stimulate cardiac rupture in one rodent model. In humans, 7 of 11 studies reported a significant association between high serum sclerostin and high carotid intima media thickness. Ten of 15 studies reported a significant association between high serum sclerostin and severe arterial calcification. Twelve of 14 studies reported a significant association between high serum sclerostin and high arterial stiffness or atherosclerosis severity. Four of 9 studies reported a significant association between high serum sclerostin and high risk of cardiovascular events. A meta-analysis of randomized controlled trials suggested that administration of the sclerostin blocking antibody romosozumab did not significantly increase the risk of major adverse cardiovascular events (risk ratio, 1.14 [95% CI, 0.83-1.57]; P=0.54) or cardiovascular death (risk ratio, 0.92 [95% CI, 0.53-1.59]; P=0.71). Human genetic studies reported variants predisposing to low arterial sclerostin expression were associated with a high risk of cardiovascular events. Overall, past research suggests a cardiovascular protective role of sclerostin but findings have been inconsistent, possibly due to variations in study design, the unique populations and models studied, and the heterogeneous methods used.