Racial and Ethnic Disparities in the Research and Care of Hereditary Angioedema Patients in the United States

Hereditary angioedema: Patient health care experiences within underrepresented racial and ethnic groups in the United States

BACKGROUND

Hereditary angioedema (HAE) is a rare disorder in which unpredictable angioedema attacks significantly affect patient quality of life. Information on patient experiences and perspectives of HAE management within underrepresented racial and ethnic groups is limited.

OBJECTIVE

To gain insight into the experiences and perspectives of medical care and treatment of HAE among underrepresented racial and ethnic groups in the United States.

METHODS

Adult patients diagnosed with having HAE who self-identified as members of an underrepresented racial and/or ethnic group were recruited to participate in a noninterventional, observational, web-based patient survey. The questionnaire included questions on medical history, current and past treatments, resource utilization, and perceived disease severity. The patient-perceived impact of HAE on the quality of life was also measured.

RESULTS

Overall, 139 patients participated in the survey; 33.1% were identified solely as "African American or Black" and 30.2% solely as "Hispanic, Latin American, Latin, or Latine, or Latinx." Before the diagnosis, 12.3% of the patients were satisfied with their HAE-related health care experiences. Many participants experienced difficulties obtaining an HAE diagnosis. Barriers to treatment include insufficient provider knowledge of HAE and misdiagnoses. More than 90% of the patients were satisfied with their care; however, patients reported 6 HAE attacks (median) in the past year and only 10.4% of the patients were attack free. Furthermore, 38.1% found it difficult or very difficult to cover the monthly out-of-pocket costs for HAE-related treatments and 24.6% felt that their provider sometimes/rarely/never considered their individual background when making medical decisions.

CONCLUSION

Barriers to HAE diagnosis and effective treatment persist among US patients from underrepresented racial and ethnic groups.

Safety and pharmacokinetics of long-acting plasma kallikrein inhibitor navenibart (STAR-0215) in healthy adults

BACKGROUND

Hereditary angioedema (HAE) is a rare, autosomal-dominant disorder characterized by bradykinin-mediated episodic, localized swelling that can be fatal. Currently approved long-term prophylactic therapies for HAE attacks incur substantial treatment burden through frequent dosing. Navenibart (STAR-0215) is a monoclonal antibody inhibitor of plasma kallikrein modified to extend circulating half-life and is under investigation for HAE prophylaxis.

OBJECTIVE

To evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of a single dose of navenibart in healthy adults and to assess the feasibility of every 3- and 6-month dosing.

METHODS

In this phase 1a study, participants were randomized 3:1 to receive placebo or navenibart in escalating (100-1200 mg) dosing cohorts. Safety outcomes, including treatment-emergent adverse events (TEAEs) and serious AEs, were monitored until the end of the study (day 224). Additional end points included pharmacokinetic parameters and inhibition of plasma kallikrein activity.

RESULTS

In total, 31 participants received navenibart and 10 received placebo. The median age of the participants was 36 years; 53.7% were male; 51.2% were Black or African American. Rates of TEAEs were similar between navenibart and placebo, and no serious AEs were reported. Navenibart-related TEAEs included injection site reactions, inclusive of erythema, pruritus, and swelling, which resolved without intervention. For all doses more than or equal to 300 mg, navenibart mean half-life ranged from 82 to 105 days and inhibition of factor XIIa-induced plasma kallikrein activity vs placebo was statistically significant (P < .05). Statistically significant inhibition of factor XIIa-induced plasma kallikrein activity vs placebo (P < .05) was observed with all doses of navenibart.

CONCLUSION

In this first-in-human study, up to 1200 mg of navenibart was well tolerated and demonstrated an extended half-life with durable plasma kallikrein inhibition.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05477160.

A comprehensive review of methodologies and application to use the real-world data and analytics platform TriNetX

Randomized controlled trials (RCTs) are the gold standard for evaluating the efficacy and safety of both pharmacological and non-pharmacological interventions. However, while they are designed to control confounders and ensure internal validity, their usually stringent inclusion and exclusion criteria often limit the generalizability of findings to broader patient populations. Moreover, RCTs are resource-intensive, frequently underpowered to detect rare adverse events, and sometimes narrowly focused due to their highly controlled environments. In contrast, real-world data (RWD), typically derived from electronic health records (EHRs) and claims databases, offers a valuable counterpart for answering research questions that may be impractical to address through RCTs. Recognizing this, the US Food and Drug Administration (FDA) has increasingly relied on real-world evidence (RWE) from RWD to support regulatory decisions and post-market surveillance. Platforms like TriNetX, that leverage large-scale RWD, facilitate collaborations between academia, industry, and healthcare organizations, and constitute an in-depth tool for retrieval and analysis of RWD. TriNetX's federated network architecture allows real-time, privacy-compliant data access, significantly enhancing the ability to conduct retrospective studies and refine clinical trial designs. With access to currently over 150 million EHRs, TriNetX has proven particularly effective in filling gaps left by RCTs, especially in the context of rare diseases, rare endpoints, and diverse patient populations. As the role of RWD in healthcare continues to expand, TriNetX stands out as a critical tool that complements traditional clinical trials, bridging the gap between controlled research environments and real-world practice. This review provides a comprehensive analysis of the methodologies and applications of the TriNetX platform, highlighting its potential contribution to advance patient care and outcomes.

Evaluating large language model performance to support the diagnosis and management of patients with primary immune disorders

BACKGROUND

Generative artificial intelligence (GAI) is transforming health care in a variety of ways; however, the present utility of GAI for supporting clinicians who treat rare disease such as primary immune disorders (PIs) is not well studied. We evaluated the ability of 6 state-of-the-art large language models (LLMs) for providing clinical guidance about PIs.

OBJECTIVE

To quantitatively and qualitatively measure the utility of current, open-source LLMs for diagnosing and providing helpful clinical decision support about PIs.

METHODS

Five expert clinical immunologists each provided 5 real-world, anonymized PI case vignettes via multi-turn prompting to 6 LLMs (OpenAI GPT-4o, Llama-3.1-8B-Instruct, Llama-3.1-70B-Instruct, Mistral-7B-Instruct-v0.3, Mistral-Large-Instruct-2407, Mixtral-8x7B-Instruct-v0.1). We assessed the diagnostic accuracy of the LLMs and the quality of clinical reasoning using the Revised-IDEA (R-IDEA) score. Qualitative LLM assessment was made by immunologist narratives.

RESULTS

Performance accuracy (>88%) and R-IDEA scores (≥8) were superior for 3 models (GPT-4o, Llama-3.1-70B-Instruct, Mistral-Large-Instruct-2407), with GPT-4o achieving the highest diagnostic accuracy (96.2%). Conversely, the remaining 3 models fell below acceptable accuracy rates near 60% or lower and had poor R-IDEA scores (≤0.55), with Mistral-7B-Instruct-v0.3 attaining the worst diagnostic accuracy (42.3%). Compared with the 3 best-performing LLMs, the 3 worst-performing LLMs had a substantially lower median R-IDEA score (P < .001). Interclass correlation coefficient for R-IDEA score assignments varied substantially by LLM, ranging from good to poor agreement, and did not appear to correlate with either diagnostic accuracy or median R-IDEA score. Qualitatively, immunologists identified several themes (eg, correctness, differential diagnosis appropriateness, relative conciseness of explanations) of relevance to PIs.

CONCLUSIONS

LLM can support diagnosis and management of PIs; however, further tuning is needed to optimize LLMs for best practice recommendations.

Epidemiology, economic, and humanistic burden of hereditary angioedema: a systematic review

BACKGROUND

This systematic study aims to assess the global epidemiologic, economic, and humanistic burden of illness associated with all types of hereditary angioedema.

METHODS

A systematic search for articles reporting the epidemiologic, economic, and humanistic burden associated with patients with HAE was conducted using English and Chinese literature databases from the inception to May 23, 2022. The selected studies were assessed for their quality and risk of bias. The study was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses and registered with the International Prospective Register of Systematic Reviews (PROSPERO; CRD42022352377).

RESULTS

In total, 65 articles that met the search inclusion criteria reported 10,310 patients with HAE, of whom 5861 were female patients. Altogether, 4312 patients (81%) and 479 patients (9%) had type 1 and type 2 HAE, respectively, whereas 422 patients (8%) had HAE-normal C1-INH. The overall prevalence of all types of HAE was between 0.13 and 1.6 cases per 100,000. The mean or median delay from the first onset of a symptom of HAE to confirmed diagnosis ranged from 3.9 to 26 years. The estimated risk of death from asphyxiation was 8.6% for patients with HAE. Hospitalization, medication, unnecessary surgeries, doctor visits, specialist services, and nursing costs are direct expenses that contribute to the growing economic burden. The indirect cost accounted mostly due to missing work ($3402/year) and loss of productivity ($5750/year). Furthermore, impairment of QoL as reported by patient-reported outcomes was observed. QoL measures identified depression, anxiety, and stress to be the most common symptoms for adult patients and children.

CONCLUSION

This study highlights the importance of early diagnosis and the need for improving awareness among health care professionals to reduce the burden of HAE on patients and society.

Epidemiology and Comorbidities of Vestibular Disorders: Preliminary Findings of the AVOCADO Study

INTRODUCTION

Studies on incidence and prevalence of vestibular disorders tend to focus on small pockets of patients recruited from specialized clinics and often exclude measures of vestibular function. The objectives of the study were to characterize patients with common vestibular disorders, estimate the prevalence of common vestibular disorders, and ascertain whether patients with vestibular disorders experience increased risks of falls and morbidity.

MATERIALS AND METHODS

This retrospective cohort study includes both inpatient and outpatient routine clinical care data culled from a nationally representative, population-based sample. Patients were included if their record in the TriNetX Diamond Cohort comprised at least one vestibular function test or vestibular diagnosis. The main outcome measures were diagnosis with a vestibular disorder, a fall, or a common medical comorbidity (e.g., diabetes, cerebrovascular disease).

RESULTS

The cohort includes n = 4,575,724 patients, of which 55% (n = 2,497,136) had a minimum of one vestibular diagnosis. Patients with vestibular diagnoses were 61.3 ± 16.6 years old (mean ± standard deviation), 67% women, 28% White race (69% unknown race), and 30% of non-Hispanic or Latino ethnicity (66% unknown ethnicity). The prevalence of vestibular disorders was estimated at 2.98% (95% confidence interval [CI]: 2.98-2.98%). Patients with vestibular diagnoses experienced a significantly greater odds of falls (odds ratio [OR] = 1.04; 95% CI: 1.02-1.05), cerebrovascular disease (OR = 1.42; 95% CI: 1.40-1.43), ischemic heart disease (OR = 1.17; 95% CI: 1.16-1.19), and diabetes (OR = 1.14; 95% CI: 1.13-1.15), among others.

DISCUSSION

Vestibular disorders affect an estimated 3% of the U.S. population, after weighting. Patients with these disorders are at greater risk for many common, consequential medical conditions.

Disparities in Diagnosis, Access to Specialist Care and Treatment for Inborn Errors of Immunity

Inborn errors of immunity represent a rapidly expanding group of genetic disorders of the immune system. Significant advances have been made in recent years in diagnosis, including using genetic testing and newborn screening; treatment, including precision therapies, gene therapy and hematopoietic stem cell transplant; and development of patient registries to inform prevalence, understand morbidity of these disorders and guide the development of clinical trials. However, significant disparities due to age, race, ethnicity, socioeconomic status, or geographic location exist in all aspects of care of patients with inborn errors of immunity, beginning with delays in diagnosis and further compounded by impaired access to specialist care and treatment, leading to a notable impact on outcomes including morbidity and mortality. Addressing and correcting these disparities will require coordinated, deliberate and prolonged effort. Proposed strategies to improve equity at different levels include public health measures such as implementing universal newborn screening, supporting expanded health insurance coverage for diagnostic testing and treatment, improving access to novel therapeutics in low and middle income countries and developing artificial intelligence / machine learning tools to reduce delays in diagnosis, particularly in rural or less developed areas where access to specialist care is limited.

Real-world experience of hereditary angioedema (HAE) in Mexico: A mixed-methods approach to describe epidemiology, diagnosis, and treatment patterns

Introduction and objectives

Due to the lack of structured and systematic information available, the aim of this study was to describe the epidemiology, diagnosis, healthcare processes, and treatment patterns of hereditary angioedema (HAE) in Mexico. To achieve this, different data sources were consulted regarding medical literature, structured health system databases, and angioedema-specialized physicians (AEP) opinion regarding HAE.

Material and methods

A mixed methods approach was conducted in 4 phases: I) systematic literature review (SLR) and meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines; II) review of national health system (NHS) databases and systematic reports; III) physician survey; and IV) an epidemiologic model. ICD 10 D84.1 encoded records from the NHS were used to estimate the number of patients with HAE attended and treated during 2019. A survey was implemented to increase understanding of the clinical profile and treatments used.

Results

A prevalence rate of 0.9/50 000 inhabitants was estimated for 2019. In the same year, an estimated 317 HAE type 1 patients were recorded in the NHS, aged ≥11 years old. The most frequent clinical symptoms were cutaneous edema (67.5%) and abdominal pain (47.9%). A severe episode with laryngeal edema appeared in 27.5% of cases. Acute episodes were mainly moderate to severe (77.0%), with an annual per capita frequency of emergency visits of 7.6 patient-year (range 1-12/patient-year). The main reasons for hospitalization corresponded to laryngeal facial, tongue, and abdominal edemas, representing 73.3% of annual ICD 10 D84.1 reported hospitalizations. The main treatments that patients with HAE received were fresh frozen plasma for acute attacks and danazol for short-term prophylaxis (STP).

Conclusions

Despite efforts to make HAE visible, according to this study, cases recognized and treated in the NHS represent only 16.6% of the estimated prevalence.

Content validation and psychometric evaluation of the Angioedema Quality of Life Questionnaire for hereditary angioedema

BACKGROUND

There is considerable burden of illness in hereditary angioedema (HAE). However, instruments to assess health-related quality of life (HRQoL) in HAE are limited. The Angioedema Quality of Life Questionnaire (AE-QoL) was developed to measure HRQoL in patients with recurrent angioedema; the validity of the AE-QoL in patients with HAE is described.

METHODS

To identify disease-related experiences with a focus on the impact of HAE on HRQoL, interviews were conducted with a group of clinician experts and patients with HAE from Canada, France, Germany, Spain, the United Kingdom, and the United States, along with a targeted literature review. Concepts were mapped to the AE-QoL to assess item relevance, interpretation, and conceptual coverage. Cognitive interviews assessed item clarity and relevance. A psychometric validation was performed using data from a phase 3 trial.

RESULTS

Interviews were conducted with seven clinicians and 40 adult patients. Patients reported 35 unique impacts of HAE on their lives, the most frequent being on work/school, social relationships, physical activities, and emotions, particularly fear/worrying and anxiety. Saturation for these impacts was reached, and all concepts covered in the AE-QoL were reported during the interviews. Patients agreed that the questionnaire items and response options were clear and relevant, and the 4-week recall period was appropriate. The psychometric validation included data from 64 patients. For AE-QoL total scores, excellent internal consistency (Cronbach's alpha > 0.90), test-retest reliability (intraclass coefficient > 0.80), convergent validity with the Sheehan Disability Scale (r = 0.663), divergent validity with the EQ-5D-5L index (r = 0.292) and EQ-VAS (r = 0.337), and known-groups validity (p < 0.0001; ɳ2 = 0.56) were demonstrated.

CONCLUSIONS

Qualitative and psychometric analyses showed that the AE-QoL is a reliable and valid instrument for measuring HRQoL in adult patients with HAE from six countries.

Epidemiology, Management, and Treatment Access of Hereditary Angioedema in the Asia Pacific Region: Outcomes From an International Survey

BACKGROUND

Hereditary angioedema (HAE) is a rare genetic disease with significant morbidity and mortality for which early diagnosis and effective therapy are critical. Many Asia Pacific (AP) countries still lack access to diagnostic tests and evidence-based therapies. Epidemiologic data from the AP is needed to formulate regional guidelines to improve standards of care for HAE.

OBJECTIVE

To investigate the estimated minimal prevalence, needs, and potential interventions for the diagnosis and management of HAE in the AP.

METHODS

A structured questionnaire was distributed to representative experts from member societies of the Asia Pacific Association of Allergy, Asthma and Clinical Immunology. Patient profiles and the presence of diagnostic facilities or tests, regional and national HAE guidelines, and patient support groups were reported and compared.

RESULTS

Completed questionnaires were received from 14 representatives of 12 member countries and territories, representing 46% of the world population. Overall minimal prevalence of HAE in the AP region was 0.02/100,000 population, with significant heterogeneity across different centers. Only one-half and one-third had registered on-demand and prophylactic medications, respectively. Few had patient support groups (58%) or regional guidelines (33%), and their existence was associated with the availability of HAE-specific medications. Availability of C1-inhibitor level testing was associated with a lower age at HAE diagnosis (P = .017).

CONCLUSIONS

Hereditary angioedema in the AP differs from that in Western countries. Hereditary angioedema-specific medications were registered in only a minority of countries and territories, but those with patient support groups or regional guidelines were more likely to have better access. Asia Pacific-specific consensus and guidelines are lacking and urgently needed.

Effectiveness and safety of lanadelumab in ethnic and racial minority subgroups of patients with hereditary angioedema: results from phase 3 studies

Background

The COVID-19 pandemic has highlighted disparities in healthcare, particularly in the United States, even though disparities have existed since the organization of the modern healthcare system. Recruitment of patients from racial and ethnic minority groups is often minimal in phase 3 clinical trials, and is further exacerbated in the case of trials for rare diseases such as hereditary angioedema (HAE). This can lead to a gap in the understanding of minority patients’ experiences with these diseases and their response to potential treatment options.

Methods

We reviewed data from phase 3 double-blind (HELP) and open-label extension (HELP OLE) trials of lanadelumab, a monoclonal antibody developed for long-term prophylaxis against attacks of HAE. Efficacy (attack rate reduction) and safety (adverse events) results from White patients were compared descriptively to those from Hispanic/Latino patients, Black/African Americans, and other minority Americans.

Results

Not surprisingly, few minorities were recruited across both studies: 9.5% Black, 2.4% Asian, and 7.1% Hispanic/Latino versus 88.1% White and 91.7% non-Hispanic/non-Latino received lanadelumab in HELP, and 4.7% Black, 0.9% Asian, 0.9% other, and 6.1% Hispanic/Latino versus 93.4% White and 93.4% non-Hispanic/non-Latino were enrolled in HELP OLE. Although these studies were conducted in the United States, Canada, Europe, and Jordan, all minorities were from the United States. Despite the number of minority patients being far less than expected for the population, there was no evidence that either efficacy or adverse event profiles differed between ethnic or racial groups.

Conclusions

The HELP and HELP OLE studies described herein recruited far fewer minorities than would be ideal to represent these populations. However, evidence suggests that the effectiveness and tolerance of lanadelumab are similar between the groups. Nonetheless, the disparity in recruitment into research for minorities has significant room for improvement.

Trial registration NCT02586805, registered 26 October 2015, https://clinicaltrials.gov/ct2/show/record/NCT02586805. NCT02741596, registered 18 April 2016, https://clinicaltrials.gov/ct2/show/NCT02741596.

Benefits and Harms of Treatment and Preventive Interventions for Hereditary Angioedema: Protocol for a Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Hereditary angioedema (HAE) is a rare genetic disease that can lead to potentially life-threatening airway attacks. Although novel therapies for HAE treatment have become available over the past decades, a comparison of all available treatments has not yet been conducted. As such, we will perform a systematic review and network meta-analysis to identify the best evidence-based treatments for the management of acute attacks and prophylaxis of HAE.

METHODS

This study will include both parallel and crossover randomized controlled trials that have investigated prevention or treatment strategies for HAE attacks. We will search electronic databases, including Medline, Embase, PubMed, Cochrane Library, Scopus, and CINAHL, from inception with no language restrictions. Potential trials will be supplemented through a gray literature search. The process of study screening, selection, data extraction, risk-of-bias assessment, certainty assessment and classification of treatments will be performed independently by a pair of reviewers. Any discrepancy will be addressed through team discussion. A two-step approach of pairwise and network meta-analysis will be performed. The summarized effect estimates of direct and indirect treatment comparisons will be pooled using DerSimonion-Laird random-effects models. The incoherence assumption, in terms of the consistency of direct and indirect effects, will be assessed. An evidence-based synthesis will be performed, based on the magnitudes of effect size, evidence certainty, and ranking of treatment effects, with respect to treatment benefits and harms.

DISCUSSION

This systematic review and network meta-analysis will summarize evidence-based conclusions with respect to the ratio of benefits and harms arising from interventions for the treatment of acute attacks and prophylaxis of HAE. Evidence from this network estimate could promote the rational use of interventions among people living with HAE in clinical practice settings. PROSPERO registration number: CRD42021251367.