Estimating the number of diseases - the concept of rare, ultra-rare, and hyper-rare

Unlocking access: a comprehensive analysis of medicines accessibility for rare diseases in Thailand

INTRODUCTION

In Thailand, obtaining medicines for rare diseases presents significant challenges, with limited evidence highlighting these issues.

OBJECTIVES

To evaluate the accessibility of medicines and the extent of health insurance coverage for treatments of rare diseases in Thailand.

METHOD

This study utilized a thorough review of current health policies, drug registration database, and insurance coverage conditions. Additionally, procurement data from the Ministry of Finance was analyzed to verify the acquisition of medicines intended for the treatment of rare diseases.

RESULTS

A review of the availability and procurement of medicines for rare diseases in Thailand revealed considerable limitations in both registration and accessibility. According to the International Rare Diseases Research Consortium, only 46.80% of their recommended medicines were registered in Thailand, and of these, just 22.93% were included in the national essential medicines list. Additionally, a review of the state's pharmaceutical procurement dataset over the past 5 years showed that merely 31.70% of these registered drugs had been purchased from suppliers for use in hospitals.

CONCLUSION

To address these issues, the study recommended accelerating the approval process for rare disease medicines, expanding health insurance coverage, establishing financial support for patients, and creating a specific pricing policy for orphan drugs. Collaborative efforts among stakeholders were emphasized as crucial for improving access to essential medicines and enhancing treatment outcomes for patients with rare diseases in Thailand.

Challenges and Possible Strategies to Address Them in Rare Disease Drug Development: A Statistical Perspective

Developing drugs for rare diseases presents unique challenges from a statistical perspective. These challenges may include slowly progressive diseases with unmet medical needs, poorly understood natural history, small population size, diversified phenotypes and genotypes within a disorder, and lack of appropriate surrogate endpoints to measure clinical benefits. The Real-World Evidence (RWE) Scientific Working Group of the American Statistical Association Biopharmaceutical Section has assembled a research team to assess the landscape including challenges and possible strategies to address these challenges and the role of real-world data (RWD) and RWE in rare disease drug development. This paper first reviews the current regulations by regulatory agencies worldwide and then discusses in more detail the challenges from a statistical perspective in the design, conduct, and analysis of rare disease clinical trials. After outlining an overall development pathway for rare disease drugs, corresponding strategies to address the challenges are presented. Other considerations are also discussed for generating relevant evidence for regulatory decision-making on drugs for rare diseases. The accompanying paper discusses how RWD and RWE can be used to improve the efficiency of rare disease drug development.

A generalist medical language model for disease diagnosis assistance

The delivery of accurate diagnoses is crucial in healthcare and represents the gateway to appropriate and timely treatment. Although recent large language models (LLMs) have demonstrated impressive capabilities in few-shot or zero-shot learning, their effectiveness in clinical diagnosis remains unproven. Here we present MedFound, a generalist medical language model with 176 billion parameters, pre-trained on a large-scale corpus derived from diverse medical text and real-world clinical records. We further fine-tuned MedFound to learn physicians' inferential diagnosis with a self-bootstrapping strategy-based chain-of-thought approach and introduced a unified preference alignment framework to align it with standard clinical practice. Extensive experiments demonstrate that our medical LLM outperforms other baseline LLMs and specialized models in in-distribution (common diseases), out-of-distribution (external validation) and long-tailed distribution (rare diseases) scenarios across eight specialties. Further ablation studies indicate the effectiveness of key components in our medical LLM training approach. We conducted a comprehensive evaluation of the clinical applicability of LLMs for diagnosis involving artificial intelligence (AI) versus physician comparison, AI-assistance study and human evaluation framework. Our proposed framework incorporates eight clinical evaluation metrics, covering capabilities such as medical record summarization, diagnostic reasoning and risk management. Our findings demonstrate the model's feasibility in assisting physicians with disease diagnosis as part of the clinical workflow.

Rare disease narratives on social media: A content analysis

Purpose

Social media provides an opportunity for the expression of people with rare conditions and may provide valuable insight into lived experiences to inform genomic care. Our objective was to describe the nature and content of rare disease video narratives on social media.

Methods

We reviewed content on a short-video-format social media website containing the tags of #raredisease, #raredisorder, or #raredisorders. Two authors independently coded videos for content matter and conducted thematic analysis using a mixed deductive-inductive approach. The demographic characteristics of the content and names of specific rare conditions were documented when available, as were the characteristics of the videos themselves.

Results

We reviewed 500 videos created by 299 unique users and identified 6 major themes: Spreading Awareness, Guidance for Others, Intimate View into Life, Interactions with Health care, Responses, and Requests for Support. The video narrators were typically family members or caregivers (50.2%) or the person affected (46.6%); a small percentage were health care professionals (2.2%). People with rare diseases in the video comprised both children (40.6%) and adults (52.6%). A total of 189 rare conditions were mentioned, the most common being Ehler-Danlos syndrome (7.8%), Sanfilippo syndrome (1.8%), and narcolepsy (1.8%).

Conclusion

Our data suggest that video-format social media allows community building among people affected by rare conditions. Insights from narratives expressed in this format may contribute to a better understanding of medical experiences in the context of daily life, both positive and negative, fostering empathy and leading to improvements in genomic medicine practice.

The book is just being written: The enduring journey of parents of children with emerging- ultrarare disorders

Ultra rare disorders are being diagnosed at an unprecedented rate, due to genomic sequencing. These diagnoses are often a new gene association, for which little is known, and few share the diagnosis. For these diagnoses, we use the term emerging-ultrarare disorder (E-URD), defined as <100 diagnosed individuals. We contacted 20 parents of children diagnosed with an E-URD through the Duke University Research Sequencing Clinic. Seventeen completed semi-structured interviews exploring parental perspectives (7/17 had children in publications describing the phenotype; 4/17 had children in the first publication establishing a new disorder). Data were analyzed using a directed content approach informed by an empowerment framework. Parents reported a range of responses, including benefits of a diagnosis and challenges of facing the unknown, some described feeling lost and confused, while others expressed empowerment. Empowerment characteristics were hope for the future, positive emotions, engagement, and confidence/self-efficacy to connect with similar others, partner with healthcare providers, and seek new knowledge. We identified a subset of parents who proactively engaged researchers, supported research and publications, and created patient advocacy and support organizations to connect with and bolster similarly diagnosed families. Other parents reported challenges of low social support, low tolerance for uncertainty, limited knowledge about their child's disorder, as well as difficulty partnering with HCPs and connecting to an E-URD community. An overarching classification was developed to describe parental actions taken after an E-URD diagnosis: adjusting, managing, and pioneering. These classifications may help genetic counselors identify and facilitate positive steps with parents of a child with an E-URD.

Telemedicine for Personalized Nutritional Intervention of Rare Diseases: A Narrative Review on Approaches, Impact, and Future Perspectives

Background: Telemedicine represents a growing opportunity to improve access to personalized care for patients with rare diseases, addressing the challenges of specialized healthcare that is often limited by geographical barriers. The aim of this narrative review is to explore how telemedicine can facilitate tailored nutritional interventions for rare diseases, focusing on inherited metabolic diseases, rare neurological disorders, such as leukodystrophies, and neuromuscular disorders, including spinal muscular atrophies. Methods: This narrative review is based on a systematic search of the published literature over the past 20 years, and includes systematic reviews, meta-analysis, retrospective studies, and original articles. References were selected through searches in databases such as PubMed and Scopus, applying predefined inclusion and exclusion criteria. Among the inclusion criteria, studies focusing on pediatric patients aged 0 to 18 years, diagnosed with rare neurological diseases or inherited metabolic disorders, and using telemedicine in addition to in-person visits at their reference center were considered. Among the exclusion criteria, studies involving patients with other pathologies or comorbidities and those involving patients older than 18 years were excluded. Results: A total of 66 documents were analyzed to examine the challenges and specific needs of patients with rare diseases, highlighting the advantages and limitations of telemedicine compared to traditional care. The use of telemedicine has revolutionized the medical approach, facilitating integrated care by multidisciplinary teams. Conclusions: Telemedicine still faces several technical, organizational, and security challenges, as well as disparities in access across different geographical areas. Emerging technologies such as artificial intelligence could positively transform the monitoring and management of patients with rare diseases. Telemedicine has great potential ahead of it in the development of increasingly personalized and effective care, in fact, emerging technologies are important to provide remote care, especially for patients with rare diseases.

[Ring chromosome 21 syndrome: report of 2 cases]

Background

When a chromosome undergoes 2 distal breaks and the broken ends join together, they form a ring chromosome. Ring 21 syndrome is described with a phenotype with minor dysmorphisms, thrombocytopenia, psychomotor and language delay. The objective of this work is to display 2 cases of male patients with ring chromosome 21.

Clinical cases

The first case was a 5-year-old male patient, with psychomotor and language delay. Broad forehead with prominent metopic suture, bilateral epicanthic fold, hypotelorism, left esotropia, low-set asymmetrical pinnae, micrognathia, lower extremities with deep plantar folds. Karyotype 46,XY,r(21)(p11.2q21)[25]. The second case was an 8-year-old male patient with psychomotor and language delay. Skull with flattened occiput, triangular facies, midfacial flattening, palpebral fissures directed downwards, bilateral epicanthic fold, low-set and asymmetrical pinnae, micrognathia, prominent asymmetrical thorax on the right side, hands with irregular palmar folds. Karyotype: 46,XY,r(21)(p11q22)[25].

Conclusion

Craniofacial dysmorphisms with psychomotor and language delay were the most relevant clinical data in both cases.

The state-of-the-art of N-of-1 therapies and the IRDiRC N-of-1 development roadmap

In recent years, a small number of people with rare diseases caused by unique genetic variants have been treated with therapies developed specifically for them. This pioneering field of genetic N-of-1 therapies is evolving rapidly, giving hope for the individualized treatment of people living with very rare diseases. In this Review, we outline the concept of N-of-1 individualized therapies, focusing on genetic therapies, and illustrate advances and challenges in the field using cases for which therapies have been successfully developed. We discuss why the traditional drug development and reimbursement pathway is not fit for purpose in this field, and outline the pragmatic, regulatory and ethical challenges this poses for future access to N-of-1 therapies. Finally, we provide a roadmap for N-of-1 individualized therapy development.

Advances in bio-polymer coatings for probiotic microencapsulation: chitosan and beyond for enhanced stability and controlled release

This review paper analyzes recent advancements in bio-polymer coatings for probiotic microencapsulation, with a particular emphasis on chitosan and its synergistic combinations with other materials. Probiotic microencapsulation is essential for protecting probiotics from environmental stresses, enhancing their stability, and ensuring effective delivery to the gut. The review begins with an overview of probiotic microencapsulation, highlighting its significance in safeguarding probiotics through processing, storage, and gastrointestinal transit. Advances in chitosan-based encapsulation are explored, including the integration of chitosan with other bio-polymers such as alginate, gelatin, and pectin, as well as the application of nanotechnology and innovative encapsulation techniques like spray drying and layer-by-layer assembly. Detailed mechanistic insights are integrated, illustrating how chitosan influences gut microbiota by promoting beneficial bacteria and suppressing pathogens, thus enhancing its role as a prebiotic or synbiotic. Furthermore, the review delves into chitosan's immunomodulatory effects, particularly in the context of inflammatory bowel disease (IBD) and autoimmune diseases, describing the immune signaling pathways influenced by chitosan and linking gut microbiota changes to improvements in systemic immunity. Recent clinical trials and human studies assessing the efficacy of chitosan-coated probiotics are presented, alongside a discussion of practical applications and a comparison of in vitro and in vivo findings to highlight real-world relevance. The sustainability of chitosan sources and their environmental impact are addressed, along with the novel concept of chitosan's role in the gut-brain axis. Finally, the review emphasizes future research needs, including the development of personalized probiotic therapies and the exploration of novel bio-polymers and encapsulation techniques.

Caregiver-Reported Economic Impacts of Pediatric Rare Diseases-A Scoping Review

Background/Objectives: Rare diseases are conditions that are individually rare but collectively common. These diseases can incur significant direct and indirect costs with a combination of high medical expenses, loss of income, and additional non-medical costs. Despite this, research into the economic cost for families of children with a rare disease is lacking. This scoping review aimed to document the evidence on the economic impacts of living with a rare disease for children and their families. Methods: Six electronic databases were searched to identify relevant peer-reviewed literature that discussed the family costs (direct medical, direct non-medical, and indirect) of having a child with a rare disease, published between January 1983 and April 2023. The geographical location, type of rare disease, and language were not limited. Data were extracted from the included studies following the screening process and are reported following the PAGER framework for reporting scoping review results. Results: The final analysis included 28 studies. The studies highlighted areas of high costs, including visits to healthcare professionals (n = 36), medication costs (n = 11), presenteeism (n = 17), and informal care (n = 11). However, gaps in the existing research, such as the focus on metabolic or musculoskeletal rare diseases and the lack of a distinction between rare and ultra-rare diseases, were apparent. Conclusions: Having a child with a rare disease can significantly impact a family's financial health, and these costs extend beyond healthcare costs. Understanding the costs experienced by the rare disease population is important to better define and comprehend the economic impact of rare diseases.

Longitudinal Analysis of Natural History Progression of Rare and Ultra-Rare Cerebellar Ataxias Using Item Response Theory

Degenerative cerebellar ataxias comprise a heterogeneous group of rare and ultra-rare genetic diseases. While disease-modifying treatments are now on the horizon for many ataxias, robust trial designs and analysis methods are lacking. To better inform trial designs, we applied item response theory (IRT) modeling to evaluate the natural history progression of several ataxias, assessed with the widely used scale for assessment and rating of ataxia (SARA). A longitudinal IRT model was built utilizing real-world data from the large autosomal recessive cerebellar ataxia (ARCA) registry. Disease progression was evaluated for the overall cohort as well as for the 10 most common ARCA genotypes. Sample sizes were calculated for simulated trials with autosomal recessive spastic ataxia Charlevoix-Saguenay (ARSACS) and polymerase gamma (POLG) ataxia, as showcased, across multiple design and analysis scenarios. Longitudinal IRT models were able to describe the changes in the latent variable underlying SARA as a function of time since ataxia onset for both the overall ARCA cohort and the common genotypes. The typical progression rates varied across genotypes between relatively high in POLG (~ 0.98 SARA points/year at SARA = 20) and very low in COQ8A ataxia (~ 0.003 SARA points/year at SARA = 20). Smaller trial sizes were required in case of faster progression, longer trials (~ 75-90% less with 5 years vs. 2 years), and larger drug effects (~ 70-80% less with 100% vs. 50% inhibition). Simulating under the developed IRT model, the longitudinal IRT model had the highest power, with a well-controlled type I error, compared to total score models or end-of-treatment analyses. The established longitudinal IRT framework allows efficient utilization of natural history data and ultimately facilitates the design and analysis of treatment trials in rare and ultra-rare genetic ataxias.

"In God We Trust": An Exploratory Study of the Associations Between Religiosity and the Caregiving Experiences of Parents of Children with Rare Diseases in Poland

Most children with a rare disease are cared for by their family members but parenting such a child is extremely demanding due to the complexity and severity of symptoms, with serious physical, emotional, social, and financial consequences for caregivers. Although religion may serve as a positive coping strategy, little is known about its role in helping caregivers manage the stress related to the burden of caregiving in Poland. Therefore, we surveyed 925 Polish family caregivers of children with rare diseases to understand the association between caregivers' religiosity and their caring experiences. The findings suggest that parents' religiosity is associated with a more positive caregiving experience, perceived quality of life, and experienced caregiving burden. While religious caregivers reported experiencing less distressing emotions and stressed the encouraging impact of their child's disease on their life more often, non-religious caregivers experienced role captivity and role overload more frequently. Since religion may serve as a source of strength and a protecting factor against mental health problems and the burden of caregiving, healthcare professionals should be aware of the importance of religious and spiritual care, and caregivers' religiosity should be considered an integral part of a holistic approach.

The relative importance of severity and rarity criteria in health resource allocation: an umbrella review

OBJECTIVES

The primary objectives of this umbrella review were to (a) quantify the relative importance, of "severity" and "rarity" criteria in health resource allocation; and (b) analyze the contextual factors influencing the relative importance. The secondary objective was to examine how "severity" and "rarity" criteria are defined.

METHODS

Searches were carried out in PubMed and Embase to identify eligible systematic reviews. Quality appraisal of systematic reviews was undertaken. From identified systematic reviews, primary studies were extracted and further screened for eligibility. The inclusion of severity and rarity criteria and their respective weights in primary studies were examined. Descriptive and regression analyses were performed.

RESULTS

Twenty-nine systematic reviews were screened, of which nine met the inclusion criteria. Primary studies included in these systematic reviews were retrieved and screened, resulting in forty articles included in the final analysis. Disease severity was more frequently considered (n = 29/40) than disease rarity (n = 23/40) as an evaluation criterion. Out of all cases where both were included as evaluation criteria, disease severity was assigned higher weights 84 percent of the time (n = 21/25).

CONCLUSIONS

Our review found consistent evidence that disease severity is more relevant and preferred to rarity as a priority-setting criterion albeit constraints in statistical analysis imposed by limited sample size and data availability. Where funding for rare diseases is concerned, we advocate that decision-makers be explicit in clarifying the significance of disease severity and/or rarity as a value driver behind decisions. Our findings also reinforce the relevance of disease severity as a criterion in priority setting.

Estimating the Number of Polygenic Diseases Among Six Mutually Exclusive Entities of Non-Tumors and Cancer

In the era of precision medicine with increasing amounts of sequenced cancer and non-cancer genomes of different ancestries, we here enumerate the resulting polygenic disease entities. Based on the cell number status, we first identified six fundamental types of polygenic illnesses, five of which are non-cancerous. Like complex, non-tumor disorders, neoplasms normally carry alterations in multiple genes, including in 'Drivers' and 'Passengers'. However, tumors also lack certain genetic alterations/epigenetic changes, recently named 'Goners', which are toxic for the neoplasm and potentially constitute therapeutic targets. Drivers are considered essential for malignant transformation, whereas environmental influences vary considerably among both types of polygenic diseases. For each form, hyper-rare disorders, defined as affecting <1/108 individuals, likely represent the largest number of disease entities. Loss of redundant tumor-suppressor genes exemplifies such a profoundly rare mutational event. For non-tumor, polygenic diseases, pathway-centered taxonomies seem preferable. This classification is not readily feasible in cancer, but the inclusion of Drivers and possibly also of epigenetic changes to the existing nomenclature might serve as initial steps in this direction. Based on the detailed genetic alterations, the number of polygenic diseases is essentially countless, but different forms of nosologies may be used to restrict the number.

An estimation of global genetic prevalence of PLA2G6-associated neurodegeneration

BACKGROUND

PLA2G6-associated neurodegeneration (PLAN) comprises three diseases with overlapping features: infantile neuroaxonal dystrophy (INAD), atypical neuroaxonal dystrophy (atypical NAD), and PLA2G6-related dystonia-parkinsonism. INAD is an early onset disease characterized by progressive loss of vision, muscular control, and mental skills. The prevalence of PLA2G6-associated diseases has not been previously calculated.

METHODS

To provide the most accurate prevalence estimate, we utilized two independent approaches: database-based approach which included collecting variants from ClinVar, Human Gene Mutation Database (HGMD) and high confidence predicted loss-of-function (pLoF) from gnomAD (Rare Genomes Project Genetic Prevalence Estimator; GeniE), and literature-based approach which gathered variants through Mastermind Genomic Search Engine (Genomenon, Inc). Genetic prevalence of PLAN was calculated based on allele frequencies from gnomAD, assuming Hardy-Weinberg equilibrium.

RESULTS

In the PLA2G6 gene, our analysis found 122 pathogenic, 82 VUS, and 15 variants with conflicting interpretations (pathogenic vs VUS) between two approaches. Allele frequency was available for 58 pathogenic, 42 VUS, and 15 conflicting variants in gnomAD database. If pathogenic and/or conflicting variants are included, the overall genetic prevalence was estimated to be between 1 in 987,267 to 1 in 1,570,079 pregnancies, with the highest genetic prevalence in African/African-American (1 in 421,960 to 1 in 365,197) and East-Asian (1 in 683,978 to 1 in 190,771) populations.

CONCLUSION

Our estimates highlight the significant underdiagnosis of PLA2G6-associated neurodegeneration and underscores the need for increased awareness and diagnostic efforts. Furthermore, our study revealed a higher carrier frequency of PLA2G6 variants in African and Asian populations, stressing the importance of expanded genetic sequencing in non-European populations to ensure accurate and comprehensive diagnosis. Future research should focus on confirming our findings and implementing expanded sequencing strategies to facilitate maximal and accurate diagnosis, particularly in non-European populations.

Emergence of the natural history of Myhre syndrome: 47 patients evaluated in the Massachusetts General Hospital Myhre Syndrome Clinic (2016-2023)

Myhre syndrome is an increasingly diagnosed ultrarare condition caused by recurrent germline autosomal dominant de novo variants in SMAD4. Detailed multispecialty evaluations performed at the Massachusetts General Hospital (MGH) Myhre Syndrome Clinic (2016-2023) and by collaborating specialists have facilitated deep phenotyping, genotyping and natural history analysis. Of 47 patients (four previously reported), most (81%) patients returned to MGH at least once. For patients followed for at least 5 years, symptom progression was observed in all. 55% were female and 9% were older than 18 years at diagnosis. Pathogenic variants in SMAD4 involved protein residues p.Ile500Val (49%), p.Ile500Thr (11%), p.Ile500Leu (2%), and p.Arg496Cys (38%). Individuals with the SMAD4 variant p.Arg496Cys were less likely to have hearing loss, growth restriction, and aortic hypoplasia than the other variant groups. Those with the p.Ile500Thr variant had moderate/severe aortic hypoplasia in three patients (60%), however, the small number (n = 5) prevented statistical comparison with the other variants. Two deaths reported in this cohort involved complex cardiovascular disease and airway stenosis, respectively. We provide a foundation for ongoing natural history studies and emphasize the need for evidence-based guidelines in anticipation of disease-specific therapies.

The Role of Patient Organizations in Shaping Research, Health Policies, and Health Services for Rare Genetic Diseases: The Dutch Experience

In 2023, the genetics scientific community celebrated two special anniversaries: the discovery of the double helix structure of DNA was published in 1953 and in 2003 the Human Genome Project was declared completed and made publicly available. To this day, genetics and genomics research is continuing to evolve at high pace and is identifying a steadily increasing number of genes as causal for distinct genetic diseases. The success story of genetics and genomics would not be complete without taking due account of the role of patient advocacy organizations in this process. This paper is based on the personal narrative (oral history) of a father whose daughter was born with a rare genetic disease (RGD) in the 1960s. The first-hand experience of living as a family with an RGD in those days made him a leading pioneer not only in the foundation of patient organizations at national, pan-European, and international levels but also in the development of multi-stakeholder co-operation and networking. Today, patient advocacy organizations play an active role in shaping health and research policies at national, EU, and international levels to ensure that their needs in regard to advancing RGD diagnostics, care, and treatment are addressed.

Feeding and Nutritional Key Features of Crisponi/Cold-Induced Sweating Syndrome

Feeding difficulties are constantly present in patients with Crisponi/cold-induced sweating syndrome type 1 (CS/CISS1). The aim of our study was to describe their prevalence and evolution from birth to adult age. We performed an observational study at the Department of Life Sciences and Public Health, Rome. Fourteen patients were included in this study (six M; mean age: 18 years; SD: 10.62 years; median age: 15 years; age range: 6-44 years); six were adults (43%). Data on oral motor abilities from birth were collected. Meal duration, presence of swallowing reflex, dysphagia symptoms, difficulty chewing, and drooling management were assessed. At birth, all patients needed enteral feeding. Introduction of solid food was postponed beyond the age of 18 months in 43% of patients. During childhood and adolescence, mealtime was characterized by increased duration (43%) accompanied by fatigue during chewing (43%), food spillage from the nasal cavities (21%), sialorrhea (86%), and poor/reduced appetite (57%). A mature rotatory chewing skill was never achieved. This report expands the phenotype description of CS/CISS1 and also improves the overall management and prevention of complications in this ultra-rare disease.

A Systematic Review of the Epidemiology and Disease Burden of Congenital and Immune-Mediated Thrombotic Thrombocytopenic Purpura

Congenital (cTTP) and immune-mediated (iTTP) thrombotic thrombocytopenic purpura are serious and rare clotting disorders resulting from a deficiency in the ADAMTS13 enzyme. A systematic review was conducted using the Ovid® MEDLINE & Embase databases to synthesize the epidemiology and burden of cTTP and iTTP worldwide (from January 1, 2010, to February 6, 2020, with an update that covered the period January 1, 2020-February 11, 2022). Outcomes of interest were incidence and prevalence of TTP, incidence of acute episodes, mortality, burden of illness (eg complications, healthcare utilization, patient-reported outcomes) and disease management. A total of 221 eligible observational studies were included. The incidence rate of acute episodes ranged from 0.19-0.35 person-years in adult patients with cTTP, and 1.81-3.93 per million persons per year for iTTP in the general population. Triggers of acute episodes were similar for cTTP and iTTP, with pregnancy and infection the most commonly observed. Exacerbation in patients with iTTP varied widely, ranging from 2.4-63.1%. All-cause mortality was observed in 0-13.4% of patients with cTTP, across studies and follow-up periods, and in 1.1% (median follow-up: 0.4 years) to 18.8% (1 year) of patients with iTTP during acute episodes. Cardiovascular, renal, and neurological disease were common complications. TTP also led to work disturbances, feelings of anxiety and depression, and general activity impairment. TTP treatment regimens used were generally reflective of current treatment guidelines. The evidence identified describes a high patient burden, highlighting the need for effective treatment regimens leading to improvements in outcomes. Considerable evidence gaps exist, particularly for disease epidemiology, patient-reported outcomes, costs of disease management, and associated healthcare resource utilization. This review may help increase disease awareness and highlights the need for additional real-world studies, particularly in geographical regions outside the United States and Western Europe.

Unlocking the full potential of rare disease drug development: exploring the not-for-profit sector's contributions to drug development and access

This commentary provides a comprehensive overview of the challenges and opportunities in the field of drug development for rare diseases and especially of gene therapy products for ultra-rare diseases. It discusses the limited market size, reimbursement and scientific complexities that deter pharmaceutical investment in this field. Highlighting the pivotal role of charitable organizations like Fondazione Telethon, it showcases their efforts in funding research and ensuring access to innovative therapies. This commentary also addresses the challenges in therapy distribution, particularly regarding sustainability and global access. It outlines Fondazione Telethon's operational model to try to address these challenges. Finally, it appeals to governments and regulatory bodies to implement policies and incentives aimed at further fostering innovation and accessibility in rare disease drug development and access.

Enhancing pediatric access to cell and gene therapies

Increasing numbers of cell and gene therapies (CGTs) are emerging to treat and cure pediatric diseases. However, small market sizes limit the potential return on investment within the traditional biopharmaceutical drug development model, leading to a market failure. In this Perspective, we discuss major factors contributing to this failure, including high manufacturing costs, regulatory challenges, and licensing practices that do not incorporate pediatric development milestones, as well as potential solutions. We propose the creation of a new entity, the Pediatric Advanced Medicines Biotech, to lead late-stage development and commercialize pediatric CGTs outside the traditional biopharmaceutical model in the United States-where organized efforts to solve this problem have been lacking. The Pediatric Advanced Medicines Biotech would partner with the academic ecosystem, manufacture products in academic good manufacturing practice facilities and work closely with regulatory bodies, to ferry CGTs across the drug development 'valley of death' and, ultimately, increase access to lifesaving treatments for children in need.

Invisible patients in rare diseases: parental experiences with the healthcare and social services for children with rare diseases. A mixed method study

This study explores the experiences of Polish caregivers of children with rare disease (CRD) with health care and social services for CRD. A mixed-methods approach was employed, using an open-ended questionnaire with a convenience sample. Quantitative data presented through descriptive statistics, were complemented by thematic analysis applied to qualitative responses. Responses from 925 caregivers of 1002 children with CRD revealed that the duration of the diagnostic journey varied, spanning from 0 to 18 years, with an average time of 1.7 years. Similarly, the average number of physicians consulted before receiving the correct diagnosis was 4.8. The Internet was basic source of information about children's disease. Although caregivers were to some extent satisfied with the quality of health care for CRD, they complained at the accessibility of health care and social services, physicians' ignorance regarding RDs, the lack of co-ordinated care and financial and psychological support. To break the cycle of the diagnostic and therapeutic odyssey that may aggravate the condition of CRD, cause parental stress and financial burden there is a need to change our view on CRD from cure to family-oriented care. Multifaceted challenges and needs of CRD families should be prioritized.

Breast Implants and the Risk of Squamous Cell Carcinoma of the Breast: A Systematic Literature Review and Epidemiologic Study

Squamous cell carcinoma may arise primarily from the breast parenchyma (PSCCB) or from the periprosthetic capsule in patients with breast implants (breast implant-associated squamous cell carcinoma [BIA-SCC]). A systematic literature review was performed to identify all PSCCB and BIA-SCC cases, and to estimate prevalence, incidence rate (IR), and risk. Studies up to November 2023 were searched on PubMed, Web of Science, Google Scholar, and Cochrane Library for predefined keywords. The numerator for PSCCB and BIA-SCC was the number of cases obtained from the literature; the denominator for PSCCB was the female population aged from 18 to 99, and the denominator for BIA-SCC was the population with breast implants. Overall, 219 papers were included, featuring 2250 PSCCB and 30 BIA-SCC cases. PSCCB prevalence was 2.0 per 100,000 (95% CI, 0.2:100,000 to 7.2:100,000) individuals, with a lifetime risk of 1:49,509 (95% CI, 0.2:10,000 to 5.6:10,000); and BIA-SCC prevalence was 0.61 per 100,000 (95% CI, 0.2:100,000 to 1.3:100,000), with a lifetime risk of 1:164,884 (95% CI, 0.2:100,000 to 5.6:100,000). The prevalence of BIA-SCC is 3.33 times lower than that of PSCCB, while the prevalence of breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is 3.84 times higher than that of primary breast ALCL. When comparing the BIA-SCC prevalence of 1:164,910 individuals with breast implants regardless of texture to the BIA-ALCL prevalence of 1:914 patients with textured implants, the BIA-SCC risk is 180 times lower than the BIA-ALCL risk. BIA-SCC occurs less frequently than PSCCB and considerably less than BIA-ALCL. The association between textured implants and BIA-SCC cases is relevant for patient education regarding uncommon and rare risks associated with breast implants, and ongoing vigilance, research, and strengthened reporting systems remain imperative.

Autosomal Recessive Infantile Hyaline Fibromatosis Identified Using Artificial Intelligence-Assisted Rapid Whole Genome Sequencing: A Rare, Multisystemic, Hereditary Disorder

Infantile hyaline fibromatosis syndrome (HFS) is an ultra-rare genetic condition characterized by the deposition of hyaline material in the skin, muscle, and viscera. Potential complications include debilitating joint contractures, coarse facial features, recurrent infections, failure to thrive, and death. Here, we present the case of a six-month-old infant with a history of painful extremity contractures, global developmental delay, neck hemangioma, and feeding intolerance presenting to our institution with abdominal distension. The multi-systemic, rapidly progressing, severe nature of her symptoms prompted consultation with inpatient pediatric genetics. Per their recommendation, rapid whole-genome sequencing (rWGS) was done with Fabric GEM®-assisted artificial intelligence (Fabric Genomics, Oakland, California, United States) at Rady Children's Hospital Institute for Genomic Medicine (San Diego, California, United States), revealing homozygous pathogenic variant c.652T>C; P.Cys218Arg in the ANTXR2 gene consistent with HFS. This case was significant not only for its rarity, but also its early manifestation of symptoms, wide range of affected body systems, and severity of symptoms, which together present a fascinating diagnostic dilemma for future clinicians that should be taken into consideration. It also highlights the increasing utility of AI-assisted rWGS as a diagnostic tool for medically complex patients with unknown multisystemic hereditary conditions.

Fair Funding Decisions: Consistency of the Time Horizons Used in the Calculation of Quality-Adjusted Life Years for Therapies for Very Rare Diseases by the National Institute for Health and Care Excellence in England

The National Institute for Health and Care Excellence (NICE) in England uses quality-adjusted life years (QALYs) to assess the cost-effectiveness of treatments. A QALY is a measure that combines the size of the clinical benefit of a treatment with the time the patient benefits from it, i.e., the time horizon. We wanted to know how consistently QALY gains are calculated at NICE. Therefore, we have analysed information on the time horizons used for the QALY calculations of the concluded evaluations conducted under the Highly Specialised Technologies programme for treatments of very rare diseases at NICE. For treatments with final guidance published by December 2023 (n = 29), a time horizon of median 97.5 years (range: 35 to 125 years) was used to calculate the QALY gains. For most QALY calculations, the accepted time horizon was longer than either the expected treatment duration or the estimated life expectancy. In contrast, for the only technology with a final negative funding decision, i.e., afamelanotide for treating the lifelong chronic disease erythropoietic protoporphyria, a time horizon that was shorter than the expected treatment duration was used. The fairness and consistency of the evaluation process of treatments for very rare diseases at NICE should be reviewed.

Evidence for common mechanisms of pathology between SHANK3 and other genes of Phelan-McDermid syndrome

Chromosome 22q13.3 deletion (Phelan-McDermid) syndrome (PMS, OMIM 606232) is a rare genetic condition that impacts neurodevelopment. PMS most commonly results from heterozygous contiguous gene deletions that include the SHANK3 gene or likely pathogenic variants of SHANK3 (PMS-SHANK3 related). Rarely, chromosomal rearrangements that spare SHANK3 share the same general phenotype (PMS-SHANK3 unrelated). Very recent human and model system studies of genes that likely contribute to the PMS phenotype point to overlap in gene functions associated with neurodevelopment, synaptic formation, stress/inflammation and regulation of gene expression. In this review of recent findings, we describe the functional overlaps between SHANK3 and six partner genes of 22q13.3 (PLXNB2, BRD1, CELSR1, PHF21B, SULT4A1, and TCF20), which suggest a model that explains the commonality between PMS-SHANK3 related and PMS-SHANK3 unrelated classes of PMS. These genes are likely not the only contributors to neurodevelopmental impairments in the region, but they are the best documented to date. The review provides evidence for the overlapping and likely synergistic contributions of these genes to the PMS phenotype.

Cryo-electron microscopy-based drug design

Structure-based drug design (SBDD) has gained popularity owing to its ability to develop more potent drugs compared to conventional drug-discovery methods. The success of SBDD relies heavily on obtaining the three-dimensional structures of drug targets. X-ray crystallography is the primary method used for solving structures and aiding the SBDD workflow; however, it is not suitable for all targets. With the resolution revolution, enabling routine high-resolution reconstruction of structures, cryogenic electron microscopy (cryo-EM) has emerged as a promising alternative and has attracted increasing attention in SBDD. Cryo-EM offers various advantages over X-ray crystallography and can potentially replace X-ray crystallography in SBDD. To fully utilize cryo-EM in drug discovery, understanding the strengths and weaknesses of this technique and noting the key advancements in the field are crucial. This review provides an overview of the general workflow of cryo-EM in SBDD and highlights technical innovations that enable its application in drug design. Furthermore, the most recent achievements in the cryo-EM methodology for drug discovery are discussed, demonstrating the potential of this technique for advancing drug development. By understanding the capabilities and advancements of cryo-EM, researchers can leverage the benefits of designing more effective drugs. This review concludes with a discussion of the future perspectives of cryo-EM-based SBDD, emphasizing the role of this technique in driving innovations in drug discovery and development. The integration of cryo-EM into the drug design process holds great promise for accelerating the discovery of new and improved therapeutic agents to combat various diseases.

Decentralisation in Clinical Trials and Patient Centricity: Benefits and Challenges

Decentralised clinical trials (DCTs) encompass various terms such as virtual, home-based, remote and siteless trials. The objectives of DCTs are to enhance the ease of participation for patients in clinical trials by minimising or removing the necessity for trial subjects to travel to the trial sites. This approach has been shown to reduce drop-out rates, increase study effectiveness and ultimately get life-altering drugs to market faster-saving sponsors billions. At the outset, DCTs deploy a wide range of digital technologies to collect safety and efficacy data from study participants, providing study treatments and performing investigations from the comfort of the patient's own home. The aim of decentralised trials includes patient centricity, enhanced efficacy in clinical trial conduct and generating real-world data. This is done by not only making it convenient for the patient to participate in the trial execution, but also involving them from the planning stage and taking their inputs during designing of trials and consenting documentation, understanding their treatment requirements and designing the studies accordingly. Various regulatory authorities have published guidelines governing DCT principles, especially after the coronavirus disease 2019 (COVID-19) experience of undertaking multicentric clinical trials. Both United States Food and Drug Administration (USFDA) and European Medicines Agency (EMA) have newer, recently updated guidelines to capture this growing reality to undertake clinical trials using patient technology or patient-centric technologies. Other regulatory agencies are accepting data generated using decentralised and patient-centric technologies and making an effort to include elements of decentralised trials in their regulatory guidelines. Decentralised trials follow a hybrid approach to have a balanced mix of remote and in-person data collection and trial procedures. Decentralised and patient-centric approaches are the future of any organisation for the conduct of clinical trials. Globally, all sponsor pharmaceutical companies must start undertaking drug development and clinical trials using a decentralised approach while keeping patient centricity in mind.

NeuroTri2-VISDOT: An open-access tool to harness the power of second trimester human single cell data to inform models of Mendelian neurodevelopmental disorders

Whole exome and genome sequencing, coupled with refined bioinformatic pipelines, have enabled improved diagnostic yields for individuals with Mendelian conditions and have led to the rapid identification of novel syndromes. For many Mendelian neurodevelopmental disorders (NDDs), there is a lack of pre-existing model systems for mechanistic work. Thus, it is critical for translational researchers to have an accessible phenotype- and genotype-informed approach for model system selection. Single-cell RNA sequencing data can be informative in such an approach, as it can indicate which cell types express a gene of interest at the highest levels across time. For Mendelian NDDs, such data for the developing human brain is especially useful. A valuable single-cell RNA sequencing dataset of the second trimester developing human brain was produced by Bhaduri et al in 2021, but access to these data can be limited by computing power and the learning curve of single-cell data analysis. To reduce these barriers for translational research on Mendelian NDDs, we have built the web-based tool, Neurodevelopment in Trimester 2 - VIsualization of Single cell Data Online Tool (NeuroTri2-VISDOT), for exploring this single-cell dataset, and we have employed it in several different settings to demonstrate its utility for the translational research community.

Ultra-rare ultra-care: Assessing the impact of caring for children with ultra rare diseases

BACKGROUND

We sought to assesses the impact of caring for children with ultra rare diseases (URDs) on family carers and to analyse the way these experiences differ among the caregivers of children diagnosed through prenatal or newborn screening, and those with symptom-based diagnosis.

METHODS

A total of 200 caregivers of 219 URDs children completed an on-line survey regarding the challenges and experiences of caregivers of URDs children.

RESULTS

The majority of URD caregivers felt burdened by their children's health problems, emotional and behavioural changes. 46.5% reported feelings of care overload, 43% coped poorly with the stress, and many experienced a variety of feelings of distress towards the role of caregiver. While most caregivers struggled with the diagnostic odyssey and were dissatisfied with the healthcare services for URD children, caregivers of children diagnosed through prenatal or newborn screening were significantly less burdened than the parents of children with symptom-based diagnoses.

CONCLUSION

Although caregivers of URDs children experience physical and emotional strain, they are often neglected by the healthcare system. A bio-psychosocial approach to URDs should therefore also include family caregivers' physical and psychosocial needs. Apart from financial and emotional support, enhancing access to genetic testing and newborn screening should be prioritised.

Development of Essential Oil Delivery Systems by 'Click Chemistry' Methods: Possible Ways to Manage Duchenne Muscular Dystrophy

Recently, rare diseases have received attention due to the need for improvement in diagnosed patients' and their families' lives. Duchenne muscular dystrophy (DMD) is a rare, severe, progressive, muscle-wasting disease. Today, the therapeutic standard for treating DMD is corticosteroids, which cause serious adverse side effects. Nutraceuticals, e.g., herbal extracts or essential oils (EOs), are possible active substances to develop new drug delivery systems to improve DMD patients' lives. New drug delivery systems lead to new drug effects, improved safety and accuracy, and new therapies for rare diseases. Herbal extracts and EOs combined with click chemistry can lead to the development of safer treatments for DMD. In this review, we focus on the need for novel drug delivery systems using EOs as the therapy for DMD and the potential use of click chemistry for drug delivery systems. New EO complex drug delivery systems may offer a new approach for improving muscle conditions and mental health issues associated with DMD. However, further research should identify the potential of these systems in the context of DMD. In this review, we discuss possibilities for applying EOs to DMD before implementing expensive research in a theoretical way.

Precision medicine in rare diseases: What is next?

Molecular diagnostics is a cornerstone of modern precision medicine, broadly understood as tailoring an individual's treatment, follow-up, and care based on molecular data. In rare diseases (RDs), molecular diagnoses reveal valuable information about the cause of symptoms, disease progression, familial risk, and in certain cases, unlock access to targeted therapies. Due to decreasing DNA sequencing costs, genome sequencing (GS) is emerging as the primary method for precision diagnostics in RDs. Several ongoing European initiatives for precision medicine have chosen GS as their method of choice. Recent research supports the role for GS as first-line genetic investigation in individuals with suspected RD, due to its improved diagnostic yield compared to other methods. Moreover, GS can detect a broad range of genetic aberrations including those in noncoding regions, producing comprehensive data that can be periodically reanalyzed for years to come when further evidence emerges. Indeed, targeted drug development and repurposing of medicines can be accelerated as more individuals with RDs receive a molecular diagnosis. Multidisciplinary teams in which clinical specialists collaborate with geneticists, genomics education of professionals and the public, and dialogue with patient advocacy groups are essential elements for the integration of precision medicine into clinical practice worldwide. It is also paramount that large research projects share genetic data and leverage novel technologies to fully diagnose individuals with RDs. In conclusion, GS increases diagnostic yields and is a crucial step toward precision medicine for RDs. Its clinical implementation will enable better patient management, unlock targeted therapies, and guide the development of innovative treatments.

Natural Course of IQSEC2-Related Encephalopathy: An Italian National Structured Survey

Pathogenic loss-of-function variants in the IQ motif and SEC7 domain containing protein 2 (IQSEC2) gene cause intellectual disability with Rett syndrome (RTT)-like features. The aim of this study was to obtain systematic information on the natural history and extra-central nervous system (CNS) manifestations for the Italian IQSEC2 population (>90%) by using structured family interviews and semi-quantitative questionnaires. IQSEC2 encephalopathy prevalence estimate was 7.0 to 7.9 × 10-7. Criteria for typical RTT were met in 42.1% of the cases, although psychomotor regression was occasionally evidenced. Genetic diagnosis was occasionally achieved in infancy despite a clinical onset before the first 24 months of life. High severity in both the CNS and extra-CNS manifestations for the IQSEC2 patients was documented and related to a consistently adverse quality of life. Neurodevelopmental delay was diagnosed before the onset of epilepsy by 1.8 to 2.4 years. An earlier age at menarche in IQSEC2 female patients was reported. Sleep disturbance was highly prevalent (60 to 77.8%), with mandatory co-sleeping behavior (50% of the female patients) being related to de novo variant origin, younger age, taller height with underweight, better social interaction, and lower life quality impact for the family and friends area. In conclusion, the IQSEC2 encephalopathy is a rare and likely underdiagnosed developmental encephalopathy leading to an adverse life quality impact.

How to START? Four pillars to optimally begin your orphan drug development

Drug development is a complex, resource intensive and long process in any disease area, and developing medicines to treat rare diseases presents even more challenges due to the small patient populations, often limited disease knowledge, heterogeneous clinical manifestations, and disease progression. However, common to all drug development programs is the need to gather as much information as possible on both the disease and the patients' needs ahead of the development path definition. Here, we propose a checklist named START, a tool that provides an overview of the key pillars to be considered when starting an orphan drug development: STakeholder mapping, Available information on the disease, Resources, and Target patient value profile. This tool helps to build solid foundations of a successful patient-centered medicines development program and guides different types of developers through a set of questions to ask for guidance through the starting phase of a rare disease therapeutic pathway.

Digital health and Clinical Patient Management System (CPMS) platform utility for data sharing of neuromuscular patients: the Italian EURO-NMD experience

BACKGROUND

The development of e-health technologies for teleconsultation and exchange of knowledge is one of the core purposes of European Reference Networks (ERNs), including the ERN EURO-NMD for rare neuromuscular diseases. Within ERNs, the Clinical Patient Management System (CPMS) is a web-based platform that seeks to boost active collaboration within and across the network, implementing data sharing. Through CPMS, it is possible to both discuss patient cases and to make patients' data available for registries and databases in a secure way. In this view, CPMS may be considered a sort of a temporary storage for patients' data and an effective tool for data sharing; it facilitates specialists' consultation since rare diseases (RDs) require multidisciplinary skills, specific, and outstanding clinical experience. Following European Union (EU) recommendation, and to promote the use of CPMS platform among EURO-NMD members, a twelve-month pilot project was set up to train the 15 Italian Health Care Providers (HCPs). In this paper, we report the structure, methods, and results of the teaching course, showing that tailored, ERN-oriented, training can significantly enhance the profitable use of the CPMS.

RESULTS

Throughout the training course, 45 professionals learned how to use the many features of the CPMS, eventually opening 98 panels of discussion-amounting to 82% of the total panels included in the EURO-NMD. Since clinical, genetic, diagnostic, and therapeutic data of patients can be securely stored within the platform, we also highlight the importance of this platform as an effective tool to discuss and share clinical cases, in order to ease both case solving and data storing.

CONCLUSIONS

In this paper, we discuss how similar course could help implementing the use of the platform, highlighting strengths and weaknesses of e-health for ERNs. The expected result is the creation of a "map" of neuromuscular patients across Europe that might be improved by a wider use of CPMS.

The Magic of Proteases: From a Procoagulant and Anticoagulant Factor V to an Equitable Treatment of Its Inherited Deficiency

Proteostasis, i.e., the homeostasis of proteins, responsible for ensuring protein turnover, is regulated by proteases, which also participate in the etiopathogenesis of multiple conditions. The magic of proteases is such that, in blood coagulation, one same molecule, such as coagulation factor V, for example, can perform both a procoagulant and an anticoagulant function as a result of the activity of proteases. However, this magic has an insidious side to it, as it may also prevent the completion of the clinical value chain of factor V deficiency. This value chain encompasses the discovery of knowledge, the transfer of this knowledge, and its translation to clinical practice. In the case of rare and ultra-rare diseases like factor V deficiency, this value chain has not been completed as the knowledge acquisition phase has dragged out over time, holding up the transfer of knowledge to clinical practice. The reason for this is related to the small number of patients afflicted with these conditions. As a result, new indications must be found to make the therapies cost-effective. In the case of factor V, significant research efforts have been directed at developing a recombinant factor V capable of resisting the action of the proteases capable of inactivating this factor. This is where bioethics and health equity considerations come into the equation.

Unlocking life-threatening COVID-19 through two types of inborn errors of type I IFNs

Since 2003, rare inborn errors of human type I IFN immunity have been discovered, each underlying a few severe viral illnesses. Autoantibodies neutralizing type I IFNs due to rare inborn errors of autoimmune regulator (AIRE)-driven T cell tolerance were discovered in 2006, but not initially linked to any viral disease. These two lines of clinical investigation converged in 2020, with the discovery that inherited and/or autoimmune deficiencies of type I IFN immunity accounted for approximately 15%-20% of cases of critical COVID-19 pneumonia in unvaccinated individuals. Thus, insufficient type I IFN immunity at the onset of SARS-CoV-2 infection may be a general determinant of life-threatening COVID-19. These findings illustrate the unpredictable, but considerable, contribution of the study of rare human genetic diseases to basic biology and public health.