Cost-Effectiveness of Cannabidiol Adjunct Therapy versus Usual Care for the Treatment of Seizures in Lennox-Gastaut Syndrome

Value of cannabidiol as adjunctive treatment for Lennox Gastaut syndrome: cost-effectiveness and budget impact analysis

BACKGROUND

Lennox-Gastaut syndrome (LGS) is a severe encephalopathic disease that leads to a decrease in the quality of life, physical injury, psychosocial impairment, and a significant increase in treatment costs. Cannabidiol (CBD) is approved for the adjunctive treatment of tonic-colonic seizures in LGS. This study aimed to determine the cost-effectiveness of CBD compared to the usual treatment in patients with LGS syndrome.

METHODS

We developed a lifetime-horizon Markov model to compare the cost-effectiveness of adjunctive CBD versus usual care. Additionally, we performed a budget impact analysis over a 5-year time horizon. The findings were presented as the incremental cost-effectiveness ratio (ICER) for CEA, with a willingness to pay threshold of $18,261 per QALY gained, and as the difference in the overall budget ($) between the scenarios with and without CBD for budget impact assessment.

RESULTS

In the base case scenario, CBD was cost-effective compared with usual care $6573 per QALY. Sensitivity analyses substantiated these results. From a healthcare perspective, there is a 77% probability that CBD is cost-effective at a willingness to pay of $18,261 per quality-adjusted life-year (QALY). Overall, the market access of CBD was associated to an increased budget of about $3,459,846 (+ 33%) in the next 5 years simulated.

CONCLUSIONS

Compared to usual care, CBD seems to be cost-effective in LGS patients and sustainable, with less than 34% overall budget increased in the next 5 years. Future studies need to confirm our results in the real word setting and in other countries.

Understanding the Burden of Lennox-Gastaut Syndrome: Implications for Patients, Caregivers, and Society in High and Low Resource Settings: A Narrative Review

Background

Lennox-Gastaut syndrome (LGS) poses significant challenges in diagnosis, management, and treatment due to its rare nature, diverse presentation, and drug-resistant seizures. While classical features aid diagnosis, challenges persist, impacting patient care and outcomes. Understanding the syndrome's burden is essential for improving healthcare policies and interventions.

Aim

This literature review aimed to comprehensively analyze clinical symptom burden, comorbidities, care requirements, quality of life (QoL), economic burden, caregiver burden, and treatment burden to pinpoint knowledge gaps for future research and intervention development, ultimately aiming to enhance the well-being of patients and caregivers.

Methods

A comprehensive literature review was conducted using electronic databases and manual searches to analyze clinical symptom burden, comorbidities, care requirements, QoL, economic burden, caregiver burden, and treatment burden associated with LGS.

Results

LGS significantly impacts the QoL for patients, with seizures, cognitive impairment, and social challenges affecting various aspects of daily living. Caregivers, particularly mothers, face significant stress and exhaustion, impacting their own health and well-being. Healthcare resource utilization is substantial, with elevated costs for LGS patients compared to controls. Cognitive impairment is prevalent and worsens over time, influencing educational and social outcomes. Prognosis varies based on factors like age of onset, underlying cause, and genetic factors, with limited treatment options available.

Conclusion

Managing LGS requires tailored approaches addressing seizures, comorbidities, and caregiver needs. While advancements in treatments and surgical techniques offer hope, challenges persist in achieving optimal outcomes and reducing the societal burden. The management of LGS involves a combination of pharmacological and nonpharmacological therapies, tailored to the individual patient's needs and response to treatment. Regular follow-up with a neurologist specialized in epilepsy is crucial for ongoing management, including annual reassessment of the diagnosis and treatment plan. The primary focus should always be on optimizing the patient's QoL, including learning and behavioral management, as complete seizure remission is rare.

A Cost-Utility Analysis of Add-On Cannabidiol Versus Usual Care Alone for the Treatment of Seizures Associated with Tuberous Sclerosis Complex in England and Wales

OBJECTIVES

The aim of this study was to evaluate the cost effectiveness of plant-derived highly purified cannabidiol (Epidyolex® in the UK; 100 mg/mL oral solution) as an add-on treatment to usual care for the management of treatment-refractory seizures associated with tuberous sclerosis complex (TSC) in patients aged ≥ 2 years.

METHODS

A cohort-based model was developed using a National Health Service perspective and lifetime horizon. Health states were based on weekly seizure frequency and seizure-free days, utilizing patient-level data from the GWPCARE6 trial (ClinicalTrials.gov identifier: NCT02544763). Two independent regression models were applied to individual patient-level data to predict seizure-free days and seizure frequency. Healthcare resource utilization data were sourced from a Delphi panel, and patient and caregiver health-related quality of life values were elicited using vignettes valued by the general public. Outcomes relating to TSC-associated neuropsychiatric disorders were modeled with costs and quality-adjusted life-years sourced from published literature.

RESULTS

In the base case, compared with usual care alone, 12 mg/kg/day cannabidiol was associated with an incremental cost-effectiveness ratio (ICER) of £23,797. The National Institute for Health and Care Excellence disease severity modifier reduced the ICER to £19,831. Probabilities of cost effectiveness at willingness-to-pay thresholds of £20,000 and £30,000 were 30% and 52%, respectively, for the base case and 39% and 66%, respectively, for the disease severity modifier. Results were robust to sensitivity and scenario analyses.

CONCLUSIONS

At 12 mg/kg/day and an ICER threshold of £20,000-£30,000, we provide evidence for the cost effectiveness of add-on cannabidiol treatment for patients with TSC-associated seizures aged ≥ 2 years who are refractory to current treatment.

The burden of illness in Lennox-Gastaut syndrome: a systematic literature review

BACKGROUND

Lennox-Gastaut syndrome (LGS) is a severe developmental and epileptic encephalopathy characterized by drug-resistant epilepsy with multiple seizure types starting in childhood, a typical slow spike-wave pattern on electroencephalogram, and cognitive dysfunction.

METHODS

We performed a systematic literature review according to the PRISMA guidelines to identify, synthesize and appraise the burden of illness in LGS (including "probable" LGS). Studies were identified by searching MEDLINE, Embase and APA PsychInfo, Cochrane's database of systematic reviews, and Epistemonikos. The outcomes were epidemiology (incidence, prevalence or mortality), direct and indirect costs, healthcare resource utilization, and patient and caregiver health-related quality of life (HRQoL).

RESULTS

The search identified 22 publications evaluating the epidemiology (n = 10), direct costs and resource (n = 10) and/or HRQoL (n = 5). No studies reporting on indirect costs were identified. With no specific ICD code for LGS in many regions, several studies had to rely upon indirect methods to identify their patient populations (e.g., algorithms to search insurance claims databases to identify "probable" LGS). There was heterogeneity between studies in how LGS was defined, the size of the populations, ages of the patients and length of the follow-up period. The prevalence varied from 4.2 to 60.8 per 100,000 people across studies for probable LGS and 2.9-28 per 100,000 for a confirmed/narrow definition of LGS. LGS was associated with high mortality rates compared to the general population and epilepsy population. Healthcare resource utilization and direct costs were substantial across all studies. Mean annual direct costs per person varied from $24,048 to $80,545 across studies, and home-based care and inpatient care were significant cost drivers. Studies showed that the HRQoL of patients and caregivers was adversely affected, although only a few studies were identified. In addition, studies suggested that seizure events were associated with higher costs and worse HRQoL. The risk of bias was low or moderate in most studies.

CONCLUSIONS

LGS is associated with a significant burden of illness featuring resistant seizures associated with higher costs and worse HRQoL. More research is needed, especially in evaluating indirect costs and caregiver burden, where there is a notable lack of studies.

Rare Neurological Diseases: an Overreview of Pathophysiology, Epidemiology, Clinical Features and Pharmacoeconomic Considerations in the Treating

Rare diseases (RD) are serious chronic diseases affecting small number of people compared to the general population. There are between 6000 and 8000 RDs, which affect about 400 million people worldwide. Drugs used for causal treatment of RDs are called orphan drugs. RDs bear great clinical and economic burden for patients, their families, healthcare systems and society overall. There are at least two reasons for the high cost of treatment of RDs. First, there is no causal therapy for majority of RDs, so exacerbations, complications, and hospitalizations in those patients are common. The second reason is high price of available orphan drugs, which are not cost-effective when traditional pharmacoeconomic evaluation is employed. The pharmacoeconomic aspect of the treatment of RDs is especially important in the field of neurology, since at least one fifth of all RDs is composed of neurological conditions. The aim of this paper was to provide a concise overview of the pathophysiological, epidemiological and clinical characteristics of some of the most important and common rare neurological diseases, with special reference to their impact on society and economy.

Cost-Effectiveness of Medicinal Cannabis for Management of Refractory Symptoms Associated With Chronic Conditions: A Systematic Review of Economic Evaluations

OBJECTIVES

Although there is a growing body of evidence suggesting that cannabinoids may relieve symptoms of some illnesses, they are relatively high-cost therapies compared with illicit growth and supply. This article aimed to comprehensively review economic evaluations of medicinal cannabis for alleviating refractory symptoms associated with chronic conditions.

METHODS

Seven electronic databases were searched for articles published up to September 6, 2020. The quality of reporting of economic evaluations was assessed using the Consolidated Health Economic Evaluation Reporting Standards checklist. The extracted data were grouped into subcategories according to types of medical conditions, organized into tables, and reported narratively.

RESULTS

This review identified 12 cost-utility analyses conducted across a variety of diseases including multiple sclerosis (MS) (N = 8), pediatric drug-resistant epilepsies (N = 2), and chronic pain (N = 2). The incremental cost-effectiveness ratio varied widely from cost saving to more than US$451 800 per quality-adjusted life-year depending on the setting, perspectives, types of medicinal cannabis, and indications. Nabiximols is a cost-effective intervention for MS spasticity in multiple European settings. Cannabidiol was found to be a cost-effective for Dravet syndrome in a Canadian setting whereas a cost-utility analysis conducted in a US setting deemed cannabidiol to be not cost-effective for Lennox-Gastaut syndrome. Overall study quality was good, with publications meeting 70% to 100% (median 83%) of the Consolidated Health Economic Evaluation Reporting Standards checklist criteria.

CONCLUSIONS

Medicinal cannabis-based products may be cost-effective treatment options for MS spasticity, Dravet syndrome, and neuropathic pain, although the literature is nascent. Well-designed clinical trials and health economic evaluations are needed to generate adequate clinical and cost-effectiveness evidence to assist in resource allocation.