An 'Adaptive Treatment Strategy' for Oral Vancomycin in Patients with the Orphan Disease Primary Sclerosing Cholangitis.

Decision-making in clinical medicine ideally is based upon evidence from randomized, placebo-controlled trials (RCTs) and subsequent systematic reviews and meta-analyses. However, for orphan diseases, the expectation of having one or multiple RCTs that inform clinical guidelines or justify specific treatments can be unrealistic and subsequent therapeutic nihilism can be detrimental to patients. This article discusses the benefits of therapeutic decision-making in the context of orphan diseases, focusing on primary sclerosing cholangitis (PSC) as an example of an orphan disease with poor clinical outcomes. PSC is a rare disorder characterized by inflammation and progressive fibrosis of the bile ducts. It carries a high risk of liver failure, malignancies, and debilitating symptoms that impair quality of life. Liver transplantation is currently the only life-prolonging intervention for PSC, but it is not a curative option. The article highlights the potential benefits of treating PSC patients with oral vancomycin (OV), which has shown significant clinical responses and improved quality of life in some cases. However, access to OV therapy is limited due to the lack of RCTs supporting its use. The standard requirement of having evidence from RCTs may result in withholding potentially life-altering and/or life-saving treatments for patients with orphan diseases. Conducting RCTs is challenging in these patient populations due to difficulties in recruiting the required patient cohorts and limited commercial returns. A standardized 'adaptive treatment strategy' is proposed to address this. This approach leverages the best available evidence for specific treatments, considers individual clinical responses, and adjusts treatment over time.

Online, home-based dystrophic epidermolysis bullosa registry.

Genetic testing is the gold standard for diagnosing different epidermolysis bullosa (EB) subtypes; however, testing rates are low. We conducted a pilot study to test feasibility of a novel, home-based registry that involved patients with EB submitting self-reported clinical symptoms using secure, online surveys (REDCap) and submitting buccal swabs for exome sequencing of EB-related genes (GeneDx). In total, 50 EB participants were enrolled, with an average age of 17 years and an average distance of 198 miles from EB specialty centers. All buccal swabs (N = 24) provided sufficient DNA for sequencing without causing mucosal trauma and 80% of participants were found to have pathogenic variants in COL7A1, the gene mutated in DEB. Participants with recessive dystrophic EB (RDEB) reported a higher prevalence of esophageal dilations (65.7% vs. 0%, p = .009) and mitten deformities of the feet (57.1% vs. 0%, p = .047) compared to non-RDEB participants.

[Consequences of a pandemic for people living with rare diseases and recommendations for maintaining healthcare and participation]. / Auswirkungen einer Pandemie auf Menschen mit Seltenen Erkrankungen und Empfehlungen zur Aufrechterhaltung von Versorgung und Teilhabe.

BACKGROUND: Rare diseases are often characterized by complex symptoms and usually require coordination of multiprofessional treatment during the diagnostic and healthcare processes. In the wake of the COVID-19 pandemic, the healthcare situation and daily life of people with rare diseases and the caregivers of children with rare diseases changed drastically. The aim of the research project RESILIENT-SE-PAN was to assess the situation of people with rare diseases and caregivers during COVID-19 and to develop recommendations based on the findings. METHODS: We conducted a mixed methods study including the perspective of people with rare diseases, caregivers and representatives from patient organizations and conducted a concluding workshop. RESULTS: The findings indicate an impact on healthcare and daily life of participants. Moreover, mental burden, supportive needs, COVID-19-specific aspects but also positive aspects were mentioned. Based on the findings from our mixed methods study, we developed 21 recommendations referring to the following topics: medical diagnostics and healthcare of the rare diseases, additional therapies and aids, access to COVID-19 information and vaccination, psychosocial support, participation and activities, patient organisations and others. DISCUSSION: The recommendations can provide an orientation for the organisation of healthcare in future crises or pandemics in order to adequately take the situations of people with rare diseases into account and consider the needs of this patient group.

Slide-to-Slide Tissue Transfer and Array Assembly From Limited Samples for Comprehensive Molecular Profiling.

Tissue microarrays (TMA) have become an important tool in high-throughput molecular profiling of tissue samples in the translational research setting. Unfortunately, high-throughput profiling in small biopsy specimens or rare tumor samples (eg, orphan diseases or unusual tumors) is often precluded owing to limited amounts of tissue. To overcome these challenges, we devised a method that allows tissue transfer and construction of TMAs from individual 2- to 5-µm sections for subsequent molecular profiling. We named the technique slide-to-slide (STS) transfer, and it requires a series of chemical exposures (so-called xylene-methacrylate exchange) in combination with rehydrated lifting, microdissection of donor tissues into multiple small tissue fragments (methacrylate-tissue tiles), and subsequent remounting on separate recipient slides (STS array slide). We developed the STS technique by assessing the efficacy and analytical performance using the following key metrics: (a) dropout rate, (b) transfer efficacy, (c) success rates using different antigen-retrieval methods, (d) success rates of immunohistochemical stains, (e) fluorescent in situ hybridization success rates, and (f) DNA and (g) RNA extraction yields from single slides, which all functioned appropriately. The dropout rate ranged from 0.7% to 6.2%; however, we applied the same STS technique successfully to fill these dropouts ("rescue" transfer). Hematoxylin and eosin assessment of donor slides confirmed a transfer efficacy of >93%, depending on the size of the tissue (range, 76%-100%). Fluorescent in situ hybridization success rates and nucleic acid yields were comparable with those of traditional workflows. In this study, we present a quick, reliable, and cost-effective method that offers the key advantages of TMAs and other molecular techniques-even when tissue is sparse. The perspectives of this technology in biomedical sciences and clinical practice are promising, given that it allows laboratories to create more data with less tissue.

Human iPSC Modeling Reveals Mutation-Specific Responses to Gene Therapy in a Genotypically Diverse Dominant Maculopathy.

Dominantly inherited disorders are not typically considered to be therapeutic candidates for gene augmentation. Here, we utilized induced pluripotent stem cell-derived retinal pigment epithelium (iPSC-RPE) to test the potential of gene augmentation to treat Best disease, a dominant macular dystrophy caused by over 200 missense mutations in BEST1. Gene augmentation in iPSC-RPE fully restored BEST1 calcium-activated chloride channel activity and improved rhodopsin degradation in an iPSC-RPE model of recessive bestrophinopathy as well as in two models of dominant Best disease caused by different mutations in regions encoding ion-binding domains. A third dominant Best disease iPSC-RPE model did not respond to gene augmentation, but showed normalization of BEST1 channel activity following CRISPR-Cas9 editing of the mutant allele. We then subjected all three dominant Best disease iPSC-RPE models to gene editing, which produced premature stop codons specifically within the mutant BEST1 alleles. Single-cell profiling demonstrated no adverse perturbation of retinal pigment epithelium (RPE) transcriptional programs in any model, although off-target analysis detected a silent genomic alteration in one model. These results suggest that gene augmentation is a viable first-line approach for some individuals with dominant Best disease and that non-responders are candidates for alternate approaches such as gene editing. However, testing gene editing strategies for on-target efficiency and off-target events using personalized iPSC-RPE model systems is warranted. In summary, personalized iPSC-RPE models can be used to select among a growing list of gene therapy options to maximize safety and efficacy while minimizing time and cost. Similar scenarios likely exist for other genotypically diverse channelopathies, expanding the therapeutic landscape for affected individuals.

Systematic analysis to identify novel disease indications and plausible potential chemical leads of glutamate ionotropic receptor NMDA type subunit 1, GRIN1.

Schizophrenia is a mental illness affecting the normal lifestyle of adults and early adolescents incurring major symptoms as jumbled speech, involvement in everyday activities eventually got reduced, patients always struggle with attention and memory, reason being both the genetic and environmental factors responsible for altered brain chemistry and structure, resulting in schizophrenia and associated orphan diseases. The network biology describes the interactions among genes/proteins encoding molecular mechanisms of biological processes, development, and diseases. Besides, all the molecular networks, protein-protein Interaction Networks have been significant in distinguishing the pathogenesis of diseases and thereby drug discovery. The present meta-analysis prioritizes novel disease indications viz. rare and orphan diseases associated with target Glutamate Ionotropic Receptor NMDA Type Subunit 1, GRIN1 using text mining knowledge-based tools. Furthermore, ZINC database was virtually screened, and binding conformation of selected compounds was performed and resulted in the identification of Narciclasine (ZINC04097652) and Alvespimycin (ZINC73138787) as potential inhibitors. Furthermore, docked complexes were subjected to MD simulation studies which suggests that the identified leads could be a better potential drug to recuperate schizophrenia.

Challenges and strategies for clinical trials in propionic and methylmalonic acidemias.

Clinical trial development in rare diseases poses significant study design and methodology challenges, such as disease heterogeneity and appropriate patient selection, identification and selection of key endpoints, decisions on study duration, choice of control groups, selection of appropriate statistical analyses, and patient recruitment. Therapeutic development in organic acidemias (OAs) shares many challenges with other inborn errors of metabolism, such as incomplete understanding of natural history, heterogenous disease presentations, requirement for sensitive outcome measures and difficulties recruiting a small sample of participants. Here, we review strategies for the successful development of a clinical trial to evaluate treatment response in propionic and methylmalonic acidemias. Specifically, we discuss crucial decisions that may significantly impact success of the study, including patient selection, identification and selection of endpoints, determination of the study duration, consideration of control groups including natural history controls, and selection of appropriate statistical analyses. The significant challenges associated with designing a clinical trial in rare disease can sometimes be successfully met through strategic engagement with experts in the rare disease, seeking regulatory and biostatistical guidance, and early involvement of patients and families.

Comprehensive mastocytosis data analysis from a single center.

Mastocytosis is a very rare disorder and is divided into three prognostically distinct variants by World Health Organization: Cutaneous mastocytosis (CM), systemic mastocytosis (SM), and mast cell sarcoma or localized mast cell (MC) tumors. The wide range of complaints may cause patients to consult various clinics, with resulting mis- or underdiagnosis. Therefore, cooperation between different subspecialties is of paramount importance. In this article, we have compiled 104 adult mastocytosis cases diagnosed and followed in our Hematology and other clinics. 86 (82.7%) of 104 patients had systemic mastocytosis. Osteoporosis, disease-related complications, and secondary malignancies are important topics in this group. We know that indolent form has great survival. But smoldering or aggressive mastocytosis has a poor prognosis. CM and indolent SM have a significantly better prognosis compared to aggressive SM (p < 0.001). We found that the presence of more than 25% of mast cells in the bone marrow, the presence of concomitant marrow dysplasia, and the presence of disease-related complications affect survival (p < 0.001). In addition to the WHO classification, the IPSM scoring system is indicative of the prognosis in this rare disease.

Addressing a broken drug pipeline for preterm birth: why early preterm birth is an orphan disease.

Preterm birth remains one of the most urgent unresolved medical problems in obstetrics, yet only 2 therapeutics for preventing preterm birth have ever been approved by the United States Food and Drug Administration, and neither remains on the market. The recent withdrawal of 17-hydroxyprogesterone caproate (17-OHPC, Makena) marks a new but familiar era for obstetrics with no Food and Drug Administration-approved pharmaceuticals to address preterm birth. The lack of pharmaceuticals reflects a broad and ineffective pipeline hindered by extensive regulatory hurdles, soaring costs of performing drug research, and concerns regarding adverse effects among a particularly vulnerable population. The pharmaceutical industry has historically limited investments in research for diseases with similarly small markets, such as cystic fibrosis, given their rarity and diminished projected financial return. The Orphan Drug Act, however, incentivizes drug development for "orphan diseases", defined as affecting <200,000 people in the United States annually. Although the total number of preterm births in the United States exceeds this threshold annually, the early subset of preterm birth (<34 weeks' gestation) would qualify, which is predominantly caused by inflammation and infection. The scientific rationale for classifying preterm birth into early and late subsets is strong given that their etiologies differ, and therapeutics that may be efficacious for one subset may not work for the other. For example, antiinflammatory therapeutics would be expected to be highly effective for early but not late preterm birth. A robust therapeutic pipeline of antiinflammatory drugs already exists, which could be used to target spontaneous early preterm birth, in combination with antibiotics shown to sterilize the amniotic cavity. New applications for therapeutics targeting spontaneous early preterm birth could categorize as orphan disease drugs, which could revitalize the preterm birth therapeutic pipeline. Herein, we describe why drugs targeting early preterm birth should qualify for orphan status, which may increase pharmaceutical interest for this vitally important obstetrical condition.

Core protocol development for phase 2/3 clinical trials in the leukodystrophy vanishing white matter: a consensus statement by the VWM consortium and patient advocates.

BACKGROUND: The leukodystrophy "Vanishing White Matter" (VWM) is an orphan disease with neurological decline and high mortality. Currently, VWM has no approved treatments, but advances in understanding pathophysiology have led to identification of promising therapies. Several investigational medicinal products are either in or about to enter clinical trial phase. Clinical trials in VWM pose serious challenges, as VWM has an episodic disease course; disease phenotype is highly heterogeneous and predictable only for early onset; and study power is limited by the small patient numbers. To address these challenges and accelerate therapy delivery, the VWM Consortium, a group of academic clinicians with expertise in VWM, decided to develop a core protocol to function as a template for trials, to improve trial design and facilitate sharing of control data, while permitting flexibility regarding other trial details. Overall aims of the core protocol are to collect safety, tolerability, and efficacy data for treatment assessment and marketing authorization. METHODS: To develop the core protocol, the VWM Consortium designated a committee, including clinician members of the VWM Consortium, family and patient group advocates, and experts in statistics, clinical trial design and alliancing with industries. We drafted three age-specific protocols, to stratify into more homogeneous patient groups, of ages ≥ 18 years, ≥ 6 to < 18 years and < 6 years. We chose double-blind, randomized, placebo-controlled design for patients aged ≥ 6 years; and open-label non-randomized natural-history-controlled design for patients < 6 years. The protocol describes study populations, age-specific endpoints, inclusion and exclusion criteria, study schedules, sample size determinations, and statistical considerations. DISCUSSION: The core protocol provides a shared uniformity across trials, enables a pool of shared controls, and reduces the total number of patients necessary per trial, limiting the number of patients on placebo. All VWM clinical trials are suggested to adhere to the core protocol. Other trial components such as choice of primary outcome, pharmacokinetics, pharmacodynamics, and biomarkers are flexible and unconstrained by the core protocol. Each sponsor is responsible for their trial execution, while the control data are handled by a shared research organization. This core protocol benefits the efficiency of parallel and consecutive trials in VWM, and we hope accelerates time to availability of treatments for VWM. TRIAL REGISTRATION: NA. From a scientific and ethical perspective, it is strongly recommended that all interventional trials using this core protocol are registered in a clinical trial register.

The Experience of a Tertiary Reference Hospital in the Study of Rare Neurological Diseases.

Background and Objectives: Rare diseases (RDs) are life-threatening or chronically impairing conditions that affect about 6% of the world's population. RDs are often called 'orphan' diseases, since people suffering from them attract little support from national health systems. Aim: The aim of this study is to describe the clinical characteristics of, and the available laboratory examinations for, patients who were hospitalized in a tertiary referral center and finally received a diagnosis associated with a Rare Neurological Disease (RND). Materials and Methods: Patients that were hospitalized in our clinic from 1 January 2014 to 31 March 2022 and were finally diagnosed with an RND were consecutively included. The RND classification was performed according to the ORPHAcode system. Results: A total of 342 out of 11.850 (2.9%) adult patients admitted to our department during this period received a diagnosis associated with an RND. The most common diagnosis (N = 80, 23%) involved an RND presenting with dementia, followed by a motor neuron disease spectrum disorder (N = 64, 18.7%). Family history indicative of an RND was present in only 21 patients (6.1%). Fifty-five (16%) people had previously been misdiagnosed with another neurological condition. The mean time delay between disease onset and diagnosis was 4.24 ± 0.41 years. Conclusions: Our data indicate that a broad spectrum of RNDs may reach a tertiary Neurological Center after a significant delay. Moreover, our data underline the need for a network of reference centers, both at a national and international level, expected to support research on the diagnosis and treatment of RND.

A systematic review and integrative sequential explanatory narrative synthesis: The psychosocial impact of parenting a child with a lysosomal storage disorder.

Lysosomal storage disorders are rare multiorgan, degenerative conditions requiring invasive treatment. Rare disorders pose unique challenges; therefore, exploring their impact is crucial for understanding family needs. This novel review aimed to understand the psychosocial outcomes for parents of children with lysosomal storage disorders. Five electronic databases were systematically searched. Thirty-eight (23 qualitative, 10 qualitative and 5 mixed methods) studies were included, analysed using a sequential explanatory narrative synthesis and appraised for their methodological quality. Quantitative data revealed the multifaceted impact on parents' psychological and social wellbeing. Qualitative data informed the challenges that these parents faced which were expressed within three main themes: (a) Uncertainty and the unknown, (b) All-encompassing impact and (c) Finding a way forward. The synthesis demonstrated that factors associated with the condition (symptoms, behaviour and severity) had a substantial negative impact on parental outcomes, upheld by concurrent loss (deterioration and poor prognosis) and uncertainty. This substantive integrated review revealed considerable unmet parental psychosocial needs.

Expectations of patient associations from a French Center for Rare Epilepsies.

Rare epilepsy centers, also called reference centers in France, have the mission to coordinate care for rare diseases, improve knowledge, and conduct research on rare diseases. Dissemination of knowledge is conducted in collaboration with patient associations. In just a few years, the Internet and social media have become the main source for news and knowledge. We conducted a survey about the use of social media and the expectations of patient associations from a rare epilepsy center. From the 29 associations on our website, 18 (62%) answered the survey, representing about 9000 members. All of the patient associations use social media. Facebook is used by all of them, and most of them also used additional social media channels. 13/18 (72%) associations found that it was easy to get in touch with our center and almost all partner associations were satisfied with the information published on our website (17/18, 94%). Eight patient associations (8/15, 53%) expected more information from us regarding scientific news (10/13) and clinical trials (8/13). Despite the existence of an active website and a monthly newsletter, the family associations interacting with our rare epilepsy center still want to collaborate even more with us. The use of social media by the rare epilepsy centers might help to fill the gap of the knowledge dissemination.

[The specialized medical care of children with rare diseases].

The article presents the results of analysis of specialized medical care of children with life threatening and chronic progressive rare (orphan) diseases resulting in life span shortening or disability. The possibility of medication support of children with rare diseases. The development of patient routing system considering characteristics of particular disease and possibilities of the subjects of the Russian Federation is one of most important directions of enhancement of needed medical care support.

Drug discovery and chemical probing in Drosophila.

Flies are increasingly utilized in drug discovery and chemical probing in vivo, which are novel technologies complementary to genetic probing in fundamental biological studies. Excellent genetic conservation, small size, short generation time, and over one hundred years of genetics make Drosophila an attractive model for rapid assay readout and use of analytical amounts of compound, enabling the experimental iterations needed in early drug development at a fraction of time and costs. Here, we describe an effective drug-testing pipeline using adult flies that can be easily implemented to study several disease models and different genotypes to discover novel molecular insight, probes, quality lead compounds, and develop novel prototype drugs.

Leg lengthening and deformity correction in rare bone diseases: a multidisciplinary approach.

Congenital and acquired conditions presenting with leg length discrepancy, leg deformity or short stature are not only a challenge for paediatric orthopaedic surgeons in terms of treatment options but may also involve a number of medical specialties due to the complex clinical manifestations of the diseases. Various surgical treatment options are available for these rare genetic diseases, including bone lengthening and growth inhibition techniques for lower limb discrepancy, as well as guided growth and other surgical procedures for correction of angular deformities. Surgical techniques may be similar, but the treatment plans and specific multidisciplinary approaches may differ. The present report is focused on paediatric orthopaedic and multidisciplinary aspects of the treatment of rare bone diseases. We address the clinical presentation of these diseases, gait and surgical procedures for conditions such as achondroplasia, X­linked hypophosphatemia and osteogenesis imperfecta. We also provide a short overview of other rare bone diseases.

Role, function and challenges of multidisciplinary centres for rare diseases exemplified for neurofibromatosis type 1 syndrome.

PURPOSE: Neurofibromatosis type 1 (NF1) syndrome is a common rare/orphan disease that manifests itself early in the paediatric age. It imposes a considerable burden upon patients as well as on caregivers. Decisions regarding optimal care often rely on several medical instances working together as a team. METHODS: The authors reviewed the literature and supplied a description of their own clinical work at the NF1 centres. RESULTS: The experience of a multidisciplinary teamwork of three NF centres was summarized in order to enhance awareness for possible multidisciplinary ways of delivery of health and health-related aspects of care to NF1 patients. Both population-focused research centres and family-focused centres were reviewed. CONCLUSIONS: Chronic rare diseases that start in the paediatric age mandate long-term follow-up most often by several disciplines. NF1 syndrome is an example of a multidisciplinary centre in order to enhance the quality of care.

Bone Disease in Nephropathic Cystinosis: Beyond Renal Osteodystrophy.

Patients with chronic kidney disease (CKD) display significant mineral and bone disorders (CKD-MBD) that induce significant cardiovascular, growth and bone comorbidities. Nephropathic cystinosis is an inherited metabolic disorder caused by the lysosomal accumulation of cystine due to mutations in the CTNS gene encoding cystinosin, and leads to end-stage renal disease within the second decade. The cornerstone of management relies on cysteamine therapy to decrease lysosomal cystine accumulation in target organs. However, despite cysteamine therapy, patients display severe bone symptoms, and the concept of "cystinosis metabolic bone disease" is currently emerging. Even though its exact pathophysiology remains unclear, at least five distinct but complementary entities can explain bone impairment in addition to CKD-MBD: long-term consequences of renal Fanconi syndrome, malnutrition and copper deficiency, hormonal disturbances, myopathy, and intrinsic/iatrogenic bone defects. Direct effects of both CTNS mutation and cysteamine on osteoblasts and osteoclasts are described. Thus, the main objective of this manuscript is not only to provide a clinical update on bone disease in cystinosis, but also to summarize the current experimental evidence demonstrating a functional impairment of bone cells in this disease and to discuss new working hypotheses that deserve future research in the field.

Functional and structural analysis of rare SLC2A2 variants associated with Fanconi-Bickel syndrome and metabolic traits.

Deleterious variants in SLC2A2 cause Fanconi-Bickel Syndrome (FBS), a glycogen storage disorder, whereas less common variants in SLC2A2 associate with numerous metabolic diseases. Phenotypic heterogeneity in FBS has been observed, but its causes remain unknown. Our goal was to functionally characterize rare SLC2A2 variants found in FBS and metabolic disease-associated variants to understand the impact of these variants on GLUT2 activity and expression and establish genotype-phenotype correlations. Complementary RNA-injected Xenopus laevis oocytes were used to study mutant transporter activity and membrane expression. GLUT2 homology models were constructed for mutation analysis using GLUT1, GLUT3, and XylE as templates. Seventeen FBS variants were characterized. Only c.457_462delCTTATA (p.Leu153_Ile154del) exhibited residual glucose uptake. Functional characterization revealed that only half of the variants were expressed on the plasma membrane. Most less common variants (except c.593 C>A (p.Thr198Lys) and c.1087 G>T (p.Ala363Ser)) exhibited similar GLUT2 transport activity as the wild type. Structural analysis of GLUT2 revealed that variants affect substrate-binding, steric hindrance, or overall transporter structure. The mutant transporter that is associated with a milder FBS phenotype, p.Leu153_Ile154del, retained transport activity. These results improve our overall understanding of the underlying causes of FBS and impact of GLUT2 function on various clinical phenotypes ranging from rare to common disease.

Approaches to Validate and Manipulate RNA Targets with Small Molecules in Cells.

RNA has become an increasingly important target for therapeutic interventions and for chemical probes that dissect and manipulate its cellular function. Emerging targets include human RNAs that have been shown to directly cause cancer, metabolic disorders, and genetic disease. In this review, we describe various routes to obtain bioactive compounds that target RNA, with a particular emphasis on the development of small molecules. We use these cases to describe approaches that are being developed for target validation, which include target-directed cleavage, classic pull-down experiments, and covalent cross-linking. Thus, tools are available to design small molecules to target RNA and to identify the cellular RNAs that are their targets.