Challenges of Cost-Effectiveness Analyses of Novel Therapeutics for Inherited Retinal Diseases

EQ-5D-5L health utility scores in Australian adults with inherited retinal diseases: A cross-sectional survey

PURPOSE

Economic evaluations of interventions for ocular disease require utility scores that accurately represent quality of life in the target population. This study aimed to describe the distribution of EQ-5D-5L utility values among Australian adults with symptomatic inherited retinal diseases (IRDs) and to assess the relationship between these scores and vision-related quality of life.

METHODS

A survey was administered predominantly online in 2021. Participants completed the EQ-5D-5L general health utility instrument, the EQ vertical visual analogue scale (EQ-VAS) and the National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25). Self-reported IRD diagnoses were classified as being associated with central or widespread retinal involvement.

RESULTS

Responses from 647 participants aged 18-93 years were included, 50.1% were men and 77.6% had an IRD associated with widespread retinal involvement. The majority reported no problems with self-care and no pain/discomfort but did report anxiety/depression and problems with work, study, housework, or family/leisure activities. Most people with widespread involvement reported problems with mobility. Median EQ-5D-5L utility was 0.88 and 0.91 among people with widespread and central involvement, respectively (age and sex-adjusted p = 0.029); and median EQ-VAS was 75 and 80, respectively (adjusted p = 0.003). A moderate curvilinear correlation was observed between EQ-5D-5L and NEI-VFQ-25 composite score (Spearman's ρ 0.69), but not all people with poor vision-related quality of life had low EQ-5D-5L utility values.

CONCLUSIONS

EQ-5D-5L health utility values are correlated with vision-related quality of life among adults with IRDs. However, the EQ-5D-5L may not be sensitive to the full impact of vision impairment on quality of life.

The economic burden of inherited retinal disease in Singapore: a prevalence-based cost-of-illness study

OBJECTIVE

To assess the economic impact of inherited retinal disease (IRD) among Singaporeans.

METHODS

IRD prevalence was calculated using population-based data. Focused surveys were conducted for sequentially enrolled IRD patients from a tertiary hospital. The IRD cohort was compared to the age- and gender-matched general population. Economic costs were expanded to the national IRD population to estimate productivity and healthcare costs.

RESULTS

National IRD caseload was 5202 cases (95% CI, 1734-11273). IRD patients (n = 95) had similar employment rates to the general population (67.4% vs. 70.7%; p = 0.479). Annual income was lower among IRD patients than the general population (SGD 19,500 vs. 27,161; p < 0.0001). Employed IRD patients had lower median income than the general population (SGD 39,000 vs. 52,650; p < 0.0001). Per capita cost of IRD was SGD 9382, with a national burden of SGD 48.8 million per year. Male gender (beta of SGD 6543, p = 0.003) and earlier onset (beta of SGD 150/year, p = 0.009) predicted productivity loss. Treatment of the most economically impacted 10% of IRD patients with an effective IRD therapy required initial treatment cost of less than SGD 250,000 (USD 188,000) for cost savings to be achieved within 20 years.

CONCLUSIONS

Employment rates among Singaporean IRD patients were the same as the general population, but patient income was significantly lower. Economic losses were driven in part by male patients with early age of onset. Direct healthcare costs contributed relatively little to the financial burden.

A Review of Cost-Effectiveness Analyses for Open Angle Glaucoma Management

PURPOSE

Cost-effectiveness analyses (CEAs) quantify and compare both costs and measures of efficacy for different interventions. As the costs of glaucoma management to patients, payers, and physicians are increasing, we seek to investigate the role of CEAs in the field of glaucoma and how such studies impact clinical management.

METHODS

We adhered to the "Preferred Reporting Items for Systematic Reviews and Meta-analyses" guidelines for our systematic review structure. Eligible studies included any full-text articles that investigated cost-effectiveness or cost-utility as it relates to the field of open angle glaucoma management in the United States. Risk of bias assessment was conducted using the validated Joanna Briggs Institute Critical Appraisal Checklist for Economic Evaluations.

RESULTS

Eighteen studies were included in the review. Dates of publication ranged from 1983 to 2021. Most of the studies were published in the 2000s and performed CEAs in the domains of treatment/therapy, screening, and adherence for patients with primary angle open glaucoma. Of the 18 articles included, 14 focused on treatment, 2 on screening, and 2 on adherence. Most of these studies focused on the cost-effectiveness of different topical medical therapies, whereas only a few studies explored laser procedures, surgical interventions, or minimally invasive procedures. Economic models using decision analysis incorporating state-transition Markov cycles or Montecarlo simulations were widely used, however, the methodology among studies was variable, with a wide spectrum of inputs, measures of outcomes, and time horizons used.

CONCLUSION

Overall, we found that cost-effectiveness research in glaucoma in the United States remains relatively unstructured, resulting in unclear and conflicting implications for clinical management.

Predictors of problems reported on the EQ-5D-3L dimensions among people with impaired vision in northern Portugal

BACKGROUND

The EQ-5D index often fails to detect the effect of ophthalmic diseases and sight loss. Investigating predictors of individual EQ-5D health dimensions might reveal the underlying reasons. The aim of this study was to investigate predictors of health dimension ratings obtained with the EQ-5D-3L from participants with impaired vision representing a spectrum of eye diseases.

METHODS

Observational cross-sectional study with participants recruited at four public hospitals in Portugal. Outpatients with visual acuity of 0.30 logMAR(6/12) or worse in the better-seeing eye were invited to participate. Participants completed two instruments: the EQ-5D-3L (measures participants' perceived health-related quality-of-life) and the Massof Activity Inventory (measures visual ability-ability to perform vision-related activities). This study used logistic regression models to identify factors associated with responses to the EQ-5D-3L.

RESULTS

The study included 492 participants, mean age 63.4 years (range = 18-93), 50% females. The most common diagnosis was diabetic retinopathy (37%). The mean visual acuity in the better seeing eye was 0.65 logMAR (SD = 0.48) and the mean visual ability was 0.62 logits (SD = 2.04), the correlation between the two was r = - 0.511 (p < 0.001). Mobility and self-care were the health dimensions with the fewest problems (1% reported extreme problems), anxiety and depression the dimension with the most problems (24% reported extreme problems). ROC curve analysis showed that the EQ-5D index was a poor predictor of cases of vision impairment whilst visual ability given was a good predictor of cases of vision impairment. Visual ability was an independent predictor of the response for all dimensions, higher ability was always associated with a reduced odds of reporting problems. The odds of reporting problems were increased for females in 3 out of 5 dimensions. Comorbidities, visual acuity and age-category were predictors of the odds of reporting problems for one dimension each.

CONCLUSIONS

The odds of reporting problems for the five health dimensions of the EQ-5D-3L were strongly influenced by the ability to perform vision-related activities (visual ability). The EQ-5D index showed poor performance at detecting vision impairment. These findings are informative and relevant for the clinic and for research evaluating the impact of eye diseases and disease treatments in ophthalmology.

The Progression of Treatment for Refractory Hypercholesterolemia: Focus on the Prospect of Gene Therapy

Refractory hypercholesterolemia (RH), including homozygous familial hypercholesterolemia (HoFH) and compound heterozygous familial hypercholesterolemia, is characterized by high levels of low-density lipoprotein cholesterol (LDL-C) despite existing cholesterol-lowering methods at maximal tolerable doses. Patients with RH have early onset and higher risk of atherosclerotic cardiovascular disease (ASCVD) under insufficient treatment. Therefore, it is urgent to seek new therapies to maintain the blood lipids in refractory hyperlipidemia at normal levels. Currently, new cholesterol-lowering strategies are on the market, not only at the protein level [i.e., bempedoic acid (inhibiting ATP-citrate lyase), alirocumab and evolocumab (monoclonal antibodies against PCSK9), evinacumab (monoclonal antibody against ANGPTL3)] but also at the transcript level [i.e., mipomersen (antisense oligonucleotide inhibiting ApoB), inclisiran (siRNA targeting PCSK9)], providing more options for RH patients to achieve their lipid-lowering targets. More RNA-based therapies targeting RH-related genes have been designed for the treatment. However, for a proportion of patients, especially those with LDLR deficiency, the available treatments are still insufficient. More recently, emerging genome engineering based on CRISPR/Cas9 techniques, and advanced delivery technologies such as lentiviral vectors, adenoviral vectors, adeno-associated viral vectors, lipid nanoparticles, and exosomes are being rapidly developed and implemented as novel therapies for RH. Gene therapy targeting RH-related genes has been successfully conducted in cells, mice, and non-human primates with high efficacy in lipid lowering and good tolerability. Especially the new generation of genome editing technique, base editing, performed in vivo with ideal lipid-lowering effect and limited occurrence of unwanted results. Excitingly, a phase I/II clinical study of LDLR gene replacement has been recently completed in RH patients, likely to be employed in clinical practice in the future. Furthermore, new targets for cholesterol reduction such as REV-ERB, G protein-coupled receptor, Ubiquitin specific peptidase 20 are continually being developed. This narrative review updates recent advances in treatment for RH, summarizes related clinical trials and preclinical studies, especially on the prospect of gene therapy.

The State of Patient-Reported Outcome Measures for Pediatric Patients with Inherited Retinal Disease

Patient-reported outcome measures (PROMs) are questionnaires that assess health outcomes meaningful to the patient. PROMs have multiple applications, such as supporting clinicians’ decision-making for patient care, understanding the impact of disease on patient functioning, and evaluating the efficacy of therapeutics. Though PROMs were developed for various eye conditions, no PROM was tailored to pediatric patients with inherited retinal disease (IRD). Hence, a literature search was conducted using MEDLINE and Embase to identify PROMs potentially relevant to this patient population. This review evaluated selected pediatric PROMs against the US Food and Drug Administration (FDA) guidelines and found restricted use in the context of IRD. As there is a need for PROMs tailored to pediatric patients with IRD, we provide a perspective on applying the International Society for Pharmacoeconomics and Outcomes Research and FDA standards on the development of PROMs specific to IRD.

Inherited retinal diseases refer to a group of genetic conditions that affect the eye’s light-sensing cells and lead to vision loss. When a patient undergoes an eye assessment, the measures used are technical (e.g., visual acuity, visual field) and do not routinely address the patient’s experience. It is increasingly evident that the technical tools used do not really reflect how patients’ vision affects their daily lives. Questionnaires designed to assess how a condition impacts a daily activity are referred to as patient-reported outcome measures. The perspective of the impact of a condition on daily activities differs between adults and children. These tools are being created to evaluate health outcomes important to the patient on the basis of their condition and age. This is especially important when determining the value of therapies from the patient perspective. To date, no such questionnaire has been designed for pediatric patients with inherited retinal disease, an important cause of blindness. We explored the literature to evaluate existing pediatric vision tools and found that those could not be used to fill this gap. Given that we found a need to develop questionnaires tailored to pediatric patients with IRD, we also provide insight into how such a tool can be created for this population.

Molecular Therapy for Choroideremia: Pre-clinical and Clinical Progress to Date

Choroideremia is an inherited retinal disease characterised by a degeneration of the light-sensing photoreceptors, supporting retinal pigment epithelium and underlying choroid. Patients present with the same symptoms as those with classic rod-cone dystrophy: (1) night blindness early in life; (2) progressive peripheral visual field loss, and (3) central vision decline with a slow progression to legal blindness. Choroideremia is monogenic and caused by mutations in CHM. Eight clinical trials (three phase 1/2, four phase 2, and one phase 3) have started (four of which are already finished) to evaluate the therapeutic efficacy of gene supplementation mediated by subretinal delivery of an adeno-associated virus serotype 2 (AAV2/2) vector expressing CHM. Furthermore, one phase 1 clinical trial has been initiated to evaluate the efficiency of a novel AAV variant to deliver CHM to the outer retina following intravitreal delivery. Lastly, a non-viral-mediated CHM replacement strategy is currently under development, which could lead to a future clinical trial. Here, we summarise the rationale behind these various studies, as well as any results published to date. The diversity of these trials currently places choroideremia at the forefront of the retinal gene therapy field. As a consequence, the trial outcomes, regardless of the results, have the potential to change the landscape of gene supplementation for inherited retinal diseases.