Update on monthly oral bisphosphonate therapy for the treatment of osteoporosis: focus on ibandronate 150 mg and risedronate 150 mg

Treatment pattern in postmenopausal women with osteoporosis: a population-based cohort study in South Korea

INTRODUCTION

The treatment landscape of postmenopausal osteoporosis (OP) in an Asian population is yet to be explored.

MATERIALS AND METHODS

We conducted a retrospective cohort study to explore treatment patterns and characteristics associated with treatment interruption in postmenopausal women diagnosed with OP between 2008 and 2014. Treatment pattern assessment included the initial distribution of OP medications and treatment interruption rate according to the treatment groups during a 3-year follow-up period. We used multivariate logistic regression to estimate odds ratio (OR) and 95% confidence interval (CI) to identify factors associated with treatment interruption.

RESULTS

Of 21,813 patients, 87.9% initiated oral bisphosphonates (BP), followed by ibandronate intravenous (IV; 5.4%), selective estrogen receptor modulators (SERMs; 5.2%), pamidronate IV (1.4%) and zoledronic acid (0.06%). Treatment interruption was most notable in the first year of treatment, with cumulative treatment interruption rates highest for oral BP (76.3%) and lowest for pamidronate IV (50.5%). Compared to oral BP users, users of ibandronate IV (OR 0.34, 95% CI 0.30-0.39), pamidronate IV (0.49, 0.39-0.63), zoledronic acid (0.26, 0.09-0.77), and SERMs (0.50, 0.44-0.57) were less likely to interrupt treatment. Of characteristics assessed, presence of rheumatoid arthritis increased the odds of treatment interruption in ibandronate IV group (3.94, 2.12-7.33), and concomitant use of glucocorticoids for oral BP (1.11, 1.03-1.19) and pamidronate IV (2.04, 1.06-3.93) groups, respectively.

CONCLUSION

Given the frequent treatment interruptions across all OP medications, our findings on the factors associated with treatment interruption will serve to implement targeted interventions in reinforcing persistence to OP treatment.

History of risedronate

Herein we review the discovery, development, commercial history and legacy of risedronate or NE-58095, a potent N-containing bisphosphonate developed by scientists at the Cincinnati Miami Valley Laboratories and the Norwich Eaton Laboratories of Procter and Gamble. It is characterized by a hydroxyl substituent (R₁) and a pyridyl-methylene substituent (R₂) at the carbon bridging two phosphonate moieties. It was shown to have greater potency than alendronate in cell-based systems while binding affinity to bone matrix was lower than alendronate, accounting for the relatively rapid offset of bone turnover inhibition when therapy is discontinued. Risedronate was shown to significantly reduce serum alkaline phosphatase and clinical features in patients with Paget's disease and was approved for this indication, at a dose of 30 mg daily for 2 months, in 1998. Formal dose response testing for treatment of osteoporosis was not performed. In large Phase 3 studies, 5 mg risedronate daily increased bone mineral density more than did the 2.5 mg dose. As a result, the 2.5 mg dose was dropped from most of the Phase 3 studies after 12 months. The 5 mg daily dose was approved for treating and preventing postmenopausal osteoporosis and glucocorticoid-induced osteoporosis in 2000. The drug was subsequently approved for treating men with osteoporosis. Following the leads of other companies, weekly and monthly preparations were developed and approved, based on non-inferiority BMD studies vs the 5 mg daily oral dose as was a unique dosing regimen of 75 mg given on 2 consecutive days each month. Finally, to overcome the effect of food on limiting the already poor gastrointestinal absorption of the drug, a once-weekly oral preparation containing the chelating agent EDTA and with an enteric coating delaying dissolution until the tablet was in the small intestine was approved in 2010 to be administered after breakfast. The Alliance for Better Bone Health, a collaboration between Procter & Gamble Pharmaceuticals and sanofi-aventis U.S. was formed to market risedronate as Actonel® and, subsequently, Actonel-EC® or Atelvia®. These drugs are still marketed by sanofi-aventis in some countries. The sale of the pharmaceutical division of Procter & Gamble to Warner Chilcott (US) was based, in large part, on the perceived value and marketability of the risedronate drugs. When marketing targets of Warner-Chilcott were not met, the rights of risedronate were sold to Allergan USA, Inc. which never actively promoted the drug. Generic forms of risedronate were introduced into the United States in 2015 but are rarely used, although several generic forms are actively marketed in other countries.

Osteoporosis treatment: why ibandronic acid?

INTRODUCTION

In this article, we have summarized the specific evidence on ibandronic acid (or ibandronate) efficacy, tolerability, and feasibility acquired from trials and clinical use.

AREAS COVERED

This critical review focuses on evidence from randomized controlled clinical trials, meta-analyses, surrogate markers, bridging trials, long-term extension studies, observational studies, clinical experiences in osteoporosis in addition to postmenopausal treatment adherence in clinical practice, and safety profile of ibandronic acid.

EXPERT OPINION

Pivotal studies on ibandronic acid efficacy in terms of antifracture effects on nonvertebral fractures had some intrinsic limitations. However, a large body of indirect evidence suggests that ibandronate has significantly sustained vertebral and nonvertebral antifracture efficacies in women with postmenopausal osteoporosis, in comparison to those observed with other nitrogen-containing bisphosphonates. Discrepancies in efficacy between the available bisphosphonate regimens appear to be a function of dose rather than to inherent differences in their respective therapeutic potential. Drugs or treatment regimens that minimize the risk of osteoporotic fractures and make the treatment of osteoporosis more convenient and suitable for patients are preferred: ibandronic acid marketed at oral doses of 150 mg once monthly and 3 mg quarterly as intravenous injection has these characteristics. The safety profile of ibandronic acid treatment appears to be good overall and in some cases better than that of other nitrogen-containing bisphosphonates.

Evidence of sustained vertebral and nonvertebral antifracture efficacy with ibandronate therapy: a systematic review

BACKGROUND

The antifracture efficacy of ibandronate at vertebral and nonvertebral sites was assessed.

METHODS

A literature review of randomized phase III clinical trials, meta-analyses or observational studies that reported fracture endpoints or surrogate markers, and compared ibandronate with placebo or an active comparator.

RESULTS

In a phase III study, 2.5 mg daily oral ibandronate reduced the incidence of new vertebral fractures versus placebo and the relative risk reduction (RRR) was sustained over 3 years (62%; p = 0.0001). In two bridging studies, oral ibandronate 150 mg once monthly and 3 mg quarterly intravenous (i.v.) were superior to oral 2.5 mg daily in producing bone mineral density (BMD) increases at all sites over 2 years (p < 0.05). These improvements were sustained over 5 years. In meta-analyses of pivotal ibandronate studies, doses equivalent to annual cumulative exposure (ACE) ≥ 10.8 mg (including 150 mg once monthly and 3 mg quarterly i.v.) significantly reduced the incidence of nonvertebral fractures versus placebo or ACE 5.5 mg (2.5 mg daily) (RRR 29.9% and 38%, respectively; p < 0.05). Therefore, prevention of nonvertebral fractures was found in all patients with the commercially available highest doses, and not only in high-risk patients as observed in randomized clinical trials with lower doses. Finally, a 12-month, observational study of claims databases reported comparable rates of nonvertebral fractures and a statistically significantly lower rate of vertebral fractures (p < 0.01) with ibandronate versus weekly bisphosphonates.

CONCLUSION

A large body of evidence suggests that ibandronate has sustained vertebral and nonvertebral antifracture efficacy in women with postmenopausal osteoporosis.

Efficacy and safety of monthly 150 mg oral ibandronate in women with postmenopausal osteoporosis: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND/AIMS

The aim of this study was to assess the efficacy and safety of monthly oral 150 mg ibandronate in women with postmenopausal osteoporosis (PMO).

METHODS

A systematic review and meta-analysis were performed to determine treatment efficacy and safety outcomes between monthly oral 150 mg ibandronate and weekly 70 mg alendronate, daily 2.5 mg ibandronate, and a placebo.

RESULTS

Eight randomized controlled trials were included in this systematic review and meta-analysis. Once-monthly 150 mg ibandronate therapy was clinically comparable to weekly 70 mg alendronate, showing increased bone mineral density (BMD) in both the lumbar spine and total hip. Pooled data from two cross-over trials showed that significantly more women with PMO preferred once-monthly ibandronate therapy to once-weekly alendronate therapy (relative risk [RR], 2.422; 95% confidence interval [CI], 2.111 to 2.825; p < 1 × 10(-8)) and found the monthly ibandronate regimen more convenient than the weekly alendronate regimen (RR, 3.096; 95% CI, 2.622 to 3.622; p < 1 × 10(-8)). Monthly 150 mg ibandronate therapy resulted in a significantly higher change in BMD of the lumbar spine than with the placebo. A once monthly 150 mg regimen produced greater increases in lumbar spine, total hip, femoral neck, and trochanter BMD than daily treatment, with a similar incidence of adverse events between the groups.

CONCLUSIONS

Once monthly 150 mg ibandronate therapy was clinically comparable to weekly 70 mg alendronate, and patients strongly preferred the convenience of monthly ibandronate over weekly alendronate. Monthly 150 mg ibandronate was superior to, and as well tolerated as, the daily treatment.

Cost of non-persistence with oral bisphosphonates in post-menopausal osteoporosis treatment in France

BACKGROUND

During the last decade, oral bisphosphonates (BP) became the most widely prescribed pharmacologic class for post-menopausal osteoporosis. However, many surveys revealed the important issue of poor persistence with those drugs resulting in a failure of treatment to reduce fracture risk sufficiently. Using a published Markov model, this study analyses the economic impact of non-persistence with bisphosphonates in the context of the introduction of generics in France.

METHODS

Direct costs of vertebral, hip and wrist fracture were assessed and included in an existing 10-year Markov model developed to analyse consequences of non-persistence. Three alternatives of comparison were set: no treatment, real-world persistence, and ideal persistence. Simulated patients' characteristics matched those from a French observational study and the real-world adherence alternative employed persistence data from published database analysis. The risk of fracture of menopausal women and the risk reduction associated with the drugs were based on results reported in clinical trials. Incremental cost-effectiveness ratios (ICERs) were calculated first between real-world adherence and no treatment alternatives, and second between ideal and real-world persistence alternatives. The cost of non-persistence was defined as the difference between total cost of ideal and real-world persistence alternatives.

RESULTS

Within fractured women population, mean costs of 10-year management of fracture were significantly different between the three alternatives with €7,239 (± €4,783), €6,711 (± €4,410) and €6,134 (± €3,945) in the no-treatment, the real-world and ideal persistence alternatives, respectively (p < 0.0001). Cost-effectiveness ratio for real-world treatment persistence compared with no-treatment alternative was found dominant and as well, alternative of ideal persistence dominated the former. Each ten percentage point of persistence gain amounted to €58 per patient, and extrapolation resulted in a global annual cost of non-persistence of over €30 million to the French health care system, with a substantial transfer from hospital to pharmacy budgets.

CONCLUSION

Within term, improving persistence with oral bisphosphonates should be economically dominant on levels currently known in real-world. Given this potential savings, ambitious adherence-enhancing interventions should be considered in osteoporotic patients.