Effects of Romosozumab with and without Active Vitamin D Analog Supplementation for Postmenopausal Osteoporosis

The Effectiveness and Safety of Romosozumab and Teriparatide in Postmenopausal Women With Osteoporosis

PURPOSE

The purpose of this observational study was to investigate the effectiveness and safety of romosozumab (ROMO) and teriparatide (TPTD) in a clinical setting.

METHODS

A total of 315 postmenopausal women were included based on the reimbursement criteria for ROMO and TPTD at the Department of Endocrinology at Aarhus University Hospital. Criteria for ROMO were bone mineral density (BMD) T-score < -2.5 (femoral neck [FN], total hip [TH], or lumbar spine [LS]) + a fragility fracture (hip, spine, pelvis, distal forearm, or proximal humerus) within 3 years. Criteria for TPTD: within 3 years, ≥ 2 vertebral fractures or 1 vertebral fracture + BMD T-score (FN, TH, or LS) < -3. Data were collected from medical records. The primary end point was percentage change from baseline in BMD (FN, TH, and LS) at month 12. BMD was measured by dual-energy x-ray absorptiometry (DXA).

RESULTS

At month 12, ROMO led to significantly (P < .001) larger increases than TPTD in BMD (FN: 4.8% vs 0.2%, TH: 5.7% vs 0.3%, and LS: 13.7% vs 9.3%). Discontinuation rate was lower with ROMO than with TPTD. Lower incidence of cardiovascular adverse events was observed with ROMO compared to TPTD. Treatment-naïve patients had nonsignificantly higher BMD increases compared to previously treated patients with both ROMO and TPTD.

CONCLUSION

Treatment with ROMO yields larger increases in BMD than TPTD after 12 months and a higher rate of completion. ROMO was associated with a higher adherence.

Verifying the effectiveness of romosozumab re-administration on bone mineral density

Upon completing romosozumab therapy for osteoporosis, sequential treatment with other agents is required. However, for patients at high fracture risk despite such therapy, re-administration of romosozumab might be a potent subsequent option to prevent additional fractures. Currently, there is insufficient real-world clinical data verifying the efficacy of romosozumab re-administration. This study evaluated its efficacy. We enrolled 72 osteoporosis patients who remained at high risk of fractures after a 12-mo course of romosozumab, followed by sequential therapy either with bisphosphonates, denosumab, or teriparatide. Patients were re-administered another 12-mo romosozumab to assess changes in bone mineral density (BMD) and the percentages of patients achieving a T-score > -2.5 at the completion. Our result exhibited that BMD at the lumbar spine and femoral neck increased significantly through the re-administration phase (p < .001). The percentage of patients achieving a T-score > -2.5 in the lumbar spine, total hip and femoral neck increased significantly compared to before initial romosozumab therapy, with the greatest improvement seen after re-administration (all p < .001). Bone formation markers increased significantly (p < .001) during re-administration, while resorption markers showed no significant change (p = .408). The impact of prior sequential therapy was also evaluated. BMD increased significantly at all sites for patients who received bisphosphonates as sequential therapy (p < .05). After denosumab therapy, significant BMD increases were observed only in the lumbar spine (p < .01), while the total hip and femoral neck showed no significant change. After teriparatide therapy, BMD temporarily decreased during the sequential period but increased significantly after romosozumab re-administration, especially in the lumbar spine and femoral neck (both p < .001). In conclusion, romosozumab re-administration is an effective treatment. Furthermore, its efficacy varies depending on the sequential therapy used, with the highest effectiveness seen in the order of teriparatide, bisphosphonates, and denosumab.

Sequential and combination therapy with romosozumab

The introduction of the bone-forming agent romosozumab has led to a dramatic improvement in osteoporosis treatment. While bisphosphonates remain the most commonly used drugs for the treatment of osteoporosis, it is recommended that patients at high risk of fractures initially receive bone-forming agents, followed by sequential treatment with bone resorption inhibitors. Romosozumab, an anti-sclerostin antibody, is an osteoporosis medication with both bone formation-stimulating and bone resorption-inhibiting properties, demonstrating significant efficacy in increasing bone mineral density and reducing fracture risk. However, due to the limited 12-month initial treatment period, sequential therapy with other osteoporosis medications is necessary following the completion of romosozumab administration. Due to the current lack of sufficient evidence regarding the use of romosozumab in sequential and combination therapies, this review aims to evaluate the efficacy of romosozumab as a sequential treatment, its effectiveness in combination with other agents, and its role in reducing new fragility fractures and increasing bone mineral density following sequential therapy after romosozumab. This review will summarize clinical trials and real-world data, providing valuable information to guide treatment decisions.

Verification of efficacy and safety of ibandronate or denosumab for postmenopausal osteoporosis after 12-month treatment with romosozumab as sequential therapy: The prospective VICTOR study

Romosozumab is a potent drug for treating postmenopausal osteoporosis but has a limited dosing period of 12 months. Bone mineral density (BMD) decreases soon after romosozumab discontinuation, thus emphasizing the importance of appropriate sequential treatment. The present VICTOR randomized controlled study compared the efficacy of ibandronate and denosumab as sequential therapy options following 12-month romosozumab treatment. Subjects completing 12 months of romosozumab administration for severe postmenopausal osteoporosis were randomly assigned to receive either ibandronate or denosumab for an additional 12 months. The primary outcome of interest was the percentage changes in BMD at the lumbar spine, total hip, and femoral neck from 12 months (completion of romosozumab) to 18 and 24 months of total treatment (6 and 12 months, respectively, after the conversion to sequential therapy). Secondary outcomes included alterations in serum bone turnover markers and the incidence of adverse events. Sixty-two subjects each in the ibandronate and denosumab groups completed the sequential therapy. The respective percentage changes in BMD at the lumbar spine from 12 months to 24 months were 2.5 % in the ibandronate group and 5.4 % in the denosumab group. At 24 months, we observed significant differences versus 12 months for both groups as well as between the groups (all P < 0.01), showing a superior ability to increase BMD at the lumbar spine for denosumab over ibandronate. BMD gains at the total hip and femoral neck exhibited comparably favorable trends. P1NP and TRACP-5b were significantly decreased from 12 to 24 months (-64.9 % and - 26.8 % in the ibandronate group and - 67.4 % and - 36.3 % in the denosumab group, respectively; all P < 0.001 versus 12 months). Several minor adverse events were recorded in both groups, none of which led to the discontinuation of the trial. The VICTOR study revealed that denosumab could be considered more effective than ibandronate, with few severe adverse events, for the enhancement of BMD as a sequential agent after romosozumab in postmenopausal osteoporosis patients.