Cost effectiveness of replacing diclofenac with a fixed combination of misoprostol and diclofenac in patients with rheumatoid arthritis

Cost-effectiveness analysis of sodium zirconium cyclosilicate for hyperkalemia among patients with chronic kidney disease or heart failure in Kuwait

INTRODUCTION

Our model was conducted from Kuwaiti payer's perspective to provide evidence on the cost-effectiveness of Sodium zirconium cyclosilicate (SZC) versus patiromer to correct and maintain serum potassium (K+) in combination with renin-angiotensin-aldosterone system inhibitors (RAASis) with different dose titration in patients with chronic kidney disease/heart failure (CKD/HF) with/without renal replacement therapy (RRT).

METHODOLOGY

The model was developed as a patient-level, fixed-time increment stochastic simulation to simulate the complexity of disease, including multiple coexisting and competing conditional risks. This model was established to compare SZC versus patiromer as a treatment for hyperkalemia (HK) among adult populations with underlying conditions of advanced CKD stages 3a-5 or HF to correct and maintain serum K + over a lifetime horizon. The clinical outcomes of SZC and patiromer were demonstrated through arm-specific K + trajectories extracted from the HARMONIZE trial and OPAL-HK trial, respectively. The utility data was captured from different studies. Direct medical cost was captured from local data from Kuwaiti hospitals. Sensitivity analyses were conducted to assess the uncertainty in the model.

RESULTS

Within different scenarios of CKD/HF, SZC was a cost-saving option, with/without RRT, whether one-off administration or repeated administration, except for one-off treatment administration among the HF cohort, which generated an incremental cost effectiveness ratio of KWD 331/quality adjusted life year (QALY). The incremental QALY of SZC ranged from 0.007 to 0.202. In addition, the savings observed with SZC fall within a range of KWD -60 to KWD -1,235 at serum K+ ≥ 5.1 mmol/L.

CONCLUSION

The evidence generated by our model recommends the inclusion of SZC as a treatment option to correct HK and maintain normal serum K + level for CKD/HF patients within the Kuwaiti healthcare system. The costs saved from reducing frequent HK episodes, RAASis discontinuation/down titration, major cardiovascular events, and hospitalization offset the drug acquisition cost of SZC.

Cost effectiveness of guanfacine extended release as an adjunctive therapy to a stimulant compared with stimulant monotherapy for the treatment of attention-deficit hyperactivity disorder in children and adolescents

BACKGROUND

Attention-deficit hyperactivity disorder (ADHD) is a common psychiatric disorder in childhood, affecting 3-7% of school-age children in the US and imposing substantial economic burden. Stimulants are considered first-line pharmacological treatment and are the most prescribed treatment for ADHD. However, approximately 30% of children with ADHD do not have an optimal response to a single stimulant and may require adjunctive therapy.

OBJECTIVE

Our objective was to conduct a cost-effectiveness analysis (CEA) of adding a non-stimulant, guanfacine extended release (GXR), to stimulants versus maintaining existing stimulant monotherapy in the treatment of ADHD in children and adolescents with suboptimal response to stimulant monotherapy.

METHODS

A 1-year Markov model was developed to estimate costs and effectiveness from a US third-party payer perspective. Effectiveness was measured by the QALY. The model assumed that patients transitioned among four health states (normal, mild, moderate and severe), defined by the Clinical Global Impression-Severity (CGI-S) scale. Transition probabilities were estimated in an ordered logit model using patient-level data from a multicentre, 9-week, double-blind, placebo-controlled, dose-optimization study, where subjects (n = 461) continued their stable morning stimulant and were randomized to GXR administered in the morning, GXR administered in the evening, or placebo. The model assumed that patients in moderate/severe health states after week 8 would discontinue ADHD treatment and remain in that state for the rest of the study period. Direct costs included drug wholesale acquisition costs and health state costs, all in $US, year 2010 values. Utility associated with each health state was obtained from the literature and disutilities associated with adverse events were applied for the first 4 weeks. One-way sensitivity analyses and probabilistic sensitivity analysis (PSA) were conducted by varying costs, utilities, adverse-event duration, and transition probabilities.

RESULTS

Compared with maintaining existing stimulant monotherapy, adding GXR to existing stimulant monotherapy was associated with an incremental drug cost of $US1016 but a lower medical cost of $US124, resulting in a total incremental cost of $US892 at 1 year. The addition of GXR to stimulants led to an incremental QALY of 0.03 and an incremental cost-effectiveness ratio (ICER) of $US31,660/QALY. In one-way sensitivity analysis, ICER values ranged from $US19,723, when 100% of patients were assumed to be severe in their initial health state, to $US46,631, when the last observed states from the clinical trial were carried forward to the end of the 1-year analysis period. PSA demonstrated a 94.6% likelihood that the ICER falls below $US50,000/QALY.

CONCLUSIONS

The impairment associated with residual ADHD symptoms after stimulant therapy is becoming increasingly recognized. This is the first analysis of the cost effectiveness of stimulants combined with an adjunctive medication. This study suggests that the adjunctive therapy of GXR with stimulants is a cost-effective treatment based on a willingness-to-pay threshold of $US50,000/QALY. This may address an unmet need among patients with suboptimal response to stimulant monotherapy.

Current considerations for the treatment of severe chronic pain: the potential for tapentadol

Studies suggest that around 20% of adults in Europe experience chronic pain, which not only has a considerable impact on their quality of life but also imposes a substantial economic burden on society. More than one-third of these people feel that their pain is inadequately managed. A range of analgesic drugs is currently available, but recent guidelines recommend that NSAIDs and COX-2 inhibitors should be prescribed cautiously. Although the short-term efficacy of opioids is good, adverse events are common and doses are frequently limited by tolerability problems. There is a perceived need for improved pharmacological treatment options. Currently, many treatment decisions are based solely on pain intensity. However, chronic pain is multifactorial and this apaproach ignores the fact that different causative mechanisms may be involved. The presence of more than one causative mechanism means that chronic pain can seldom be controlled by a single agent. Therefore, combining drugs with different analgesic actions increases the probability of interrupting the pain signal, but is often associated with an increased risk of drug/drug interactions, low compliance and increased side effects. Tapentadol combines μ-opioid receptor agonism and noradrenaline reuptake inhibition in a single molecule, with both mechanisms contributing to its analgesic effects. Preclinical testing has shown that μ-opioid agonism is primarily responsible for analgesia in acute pain, whereas noradrenaline reuptake inhibition is more important in chronic pain. In clinical trials in patients with chronic pain, the efficacy of tapentadol was similar to that of oxycodone, but it produced significantly fewer gastrointestinal side-effects and treatment discontinuations. Pain relief remained stable throughout a 1-year safety study. Thus, tapentadol could possibly overcome some of the limitations of currently available analgesics for the treatment of chronic pain.

An economic approach to health care

Economic analyses have the potential to put all of the positive and negative outcomes of an intervention into perspective to aid decision making. The quality of the data upon which the analysis is based has an impact on the resulting quality of the analysis itself. Analysis of cost-effectiveness requires the input of many types of data, and where data are not available, assumptions must be made. There are many instances where the analysis may go wrong, and it is important to remain cognizant of these. The critical parts of the analysis, which have also been identified in quality assessment tools, include the following: design of the study question, sources of probability estimates and cost data, sensitivity analysis, and the interpretation of results. If the readers are able to identify the assumptions of the analysis they are better equipped to judge the validity. We have reviewed economic analyses relating to two hot economic topics in rheumatology. These are the cost-effectiveness of cyclooxygenase-2 (COX-2) inhibitors for 'arthritis' and cost-effectiveness of anti-tumor necrosis factor alpha (anti-TNF) agents for rheumatoid arthritis (RA). The results of the COX-2 analyses vary by review. Some show cost savings, while others calculate a significant cost in order to achieve any change in quality of life. Given the unanswered questions that still exist, it seems reasonable to conclude that COX-2 inhibitors may be cost effective when used in patients at a high risk of GI complications. Unanswered questions remain regarding the concomitant use of low-dose ASA and proton pump inhibitors and how they may affect the results of these economic analyses. The cost-effectiveness of anti-TNF agents has not been explored in as much detail as that of the COX-2 agents. Two studies have presented cost-effectiveness models that include a hypothetical biologic agent. Two economic analyses report on the cost-effectiveness of etanercept compared with traditional disease-modifying anti-rheumatic drugs (DMARDs) in methotrexate-resistant and methotrexate-naïve patients with RA. Both the analyses show that etanercept has a cost-effectiveness ratio of around 40,000 US dollars for every patient who achieves an American College of Rheumatology 20% improvement score (ACR 20) within a 6-month period. A cost-utility analysis was published regarding the use of infliximab in methotrexate resistant RA. It showed a cost-utility ratio of 3400:34,000 Euro per quality adjusted life year (QALY) gained, depending on the country evaluated (Sweden and the UK, respectively). An important finding in all three studies was that indirect costs dominate costs in RA; therefore, they should be included in all future analyses of this disease.

Cost-effectiveness analysis of NSAIDs, NSAIDs with concomitant therapy to prevent gastrointestinal toxicity, and COX-2 specific inhibitors in the treatment of rheumatoid arthritis

The objective was to assess the cost-effectiveness of nonsteroidal anti-inflammatory agents (NSAIDs), NSAIDs with concomitant therapy to prevent gastrointestinal (GI) toxicity, and cyclooxygenase-2 specific inhibitors (COX-2) in the treatment of rheumatoid arthritis (RA). Markov (state-transition) models were used to simulate a cohort taking disease-modifying antirheumatic drugs, low dose steroid, and one of the following strategies: (1) NSAIDs without prophylaxis, (2) NSAIDs with misoprostol, (3) NSAIDs with proton-pump inhibitor (PPI), or (4) COX-2. Costs were measured in 1999 US dollars and health effects are expressed as quality-adjusted life years (QALYs). COX-2 was the most cost-effective strategy for preventing GI toxicity. The incremental cost/effectiveness (C/E) ratio between COX-2 and no prophylaxis was 56,751 dollar/QALY. Although COX-2 are the best option (among the strategies analyzed) to prevent GI toxicity, the incremental C/E ratio between COX-2 and no prophylaxis is higher than 50,000 dollar/QALY.

Gastrointestinal side effects of NSAIDs - pharmacoeconomic implications

NSAIDs are frequently used as analgesics. They have a high incidence of GI adverse effects that have both social and economic costs. These costs impose a considerable strain on healthcare resources. This review discusses the epidemiology and economic cost of these adverse GI events. It also highlights the variability in risk and the impact of newer drugs. Risk stratification and the subsequent guided use of NSAIDs is likely to limit the pharmacoeconomic implications.