Health Aff (Millwood). 2024 Jan;43(1):18-26. doi: 10.1377/hlthaff.2023.00219.

ABSTRACT

The Orphan Drug Act of 1983 was enacted to provide financial incentives to stimulate drug development for rare diseases. In recent years, concerns have been raised regarding these orphan drugs, including how many are being approved for both rare and common diseases and the number of subsequent indication approvals. Policy makers have suggested modifications to the Orphan Drug Act's incentives to address these concerns. In this study we investigated the approval "family trees" of orphan drugs. We found that 491 novel orphan drugs were approved between 1990 and 2022. To date, 65 percent have been approved for a single rare disease, 15 percent have been approved for multiple rare diseases, and 20 percent have been approved for both rare and common diseases. Ten percent of orphan drugs received a subsequent indication approval for a pediatric population of an orphan disease. Revenue estimates from 2021 show that one-third of the drugs approved for both rare and common indications and 6 percent of rare-only drugs were among the 200 top-selling drugs worldwide. The results have implications for the possible externalities of modifying the incentives of the Orphan Drug Act, such as a potential decrease in the initiation of programs to develop pediatric rare disease drugs.

PMID:38190603 | DOI:10.1377/hlthaff.2023.00219

Indian J Anaesth. 2023 Nov;67(Suppl 4):S300-S301. doi: 10.4103/ija.ija_406_23. Epub 2023 Nov 21.

NO ABSTRACT

PMID:38187970 | PMC:PMC10768896 | DOI:10.4103/ija.ija_406_23

JIMD Rep. 2023 Nov 27;65(1):17-24. doi: 10.1002/jmd2.12401. eCollection 2024 Jan.

ABSTRACT

Mucopolysaccharidosis II (MPS II) is a rare, life-limiting lysosomal storage disease caused by reduced iduronate-2-sulfatase activity. Patients experience broad ranging signs and symptoms, including bone and joint manifestations. This study reported on orthopedic involvement and management in patients with MPS II using 15 years of data from the Hunter Outcome Survey (HOS). Of the 245 patients in the study population, 90.2% had skeletal deformity (median onset, 2.8 years), 76.7% had upper body stiffness (onset, 4.2 years), and 61.2% had lower body stiffness (onset, 5.3 years); 63.7% of patients had at least three joint manifestations. Orthopedic manifestations were common in adults and children with MPS II, and in patients with and without cognitive impairment. Joint range of motion (JROM) was restricted in all joints assessed (shoulder, elbow, hip, wrist, knee, and ankle). Little correlation was observed between JROM measurements, subjective reports of joint stiffness and limited function, and 6-minute walk test results. Patients with joint stiffness and limited function were generally more likely to have central and peripheral nervous system, pulmonary, and cardiovascular manifestations than those without these symptoms. Carpal tunnel decompression was the most common orthopedic surgery (recorded in 49/245 patients [20.0%]), but orthopedic surgeries were uncommon overall. Our findings highlight the need for routine monitoring of orthopedic manifestations using multiple assessment types in patients with MPS II to help inform clinical decision-making and improve patient quality of life. They also underline the contribution of factors other than orthopedic manifestations to the walking ability of patients with MPS II.

PMID:38186847 | PMC:PMC10764199 | DOI:10.1002/jmd2.12401

BMC Med Res Methodol. 2024 Jan 6;24(1):5. doi: 10.1186/s12874-023-02125-x.

ABSTRACT

BACKGROUND: In the last decades, medical research fields studying rare conditions such as spinal cord injury (SCI) have made extensive efforts to collect large-scale data. However, most analysis methods rely on complete data. This is particularly troublesome when studying clinical data as they are prone to missingness. Often, researchers mitigate this problem by removing patients with missing data from the analyses. Less commonly, imputation methods to infer likely values are applied.

OBJECTIVE: Our objective was to study how handling missing data influences the results reported, taking the example of SCI registries. We aimed to raise awareness on the effects of missing data and provide guidelines to be applied for future research projects, in SCI research and beyond.

METHODS: Using the Sygen clinical trial data (n = 797), we analyzed the impact of the type of variable in which data is missing, the pattern according to which data is missing, and the imputation strategy (e.g. mean imputation, last observation carried forward, multiple imputation).

RESULTS: Our simulations show that mean imputation may lead to results strongly deviating from the underlying expected results. For repeated measures missing at late stages (> = 6 months after injury in this simulation study), carrying the last observation forward seems the preferable option for the imputation. This simulation study could show that a one-size-fit-all imputation strategy falls short in SCI data sets.

CONCLUSIONS: Data-tailored imputation strategies are required (e.g., characterisation of the missingness pattern, last observation carried forward for repeated measures evolving to a plateau over time). Therefore, systematically reporting the extent, kind and decisions made regarding missing data will be essential to improve the interpretation, transparency, and reproducibility of the research presented.

PMID:38184529 | DOI:10.1186/s12874-023-02125-x

Pediatr Rheumatol Online J. 2024 Jan 5;22(1):12. doi: 10.1186/s12969-023-00947-z.

ABSTRACT

Haploinsufficiency of A20 (HA20) is a rare monogenic disease caused by heterozygous loss-of-function mutations in the tumor necrosis factor alpha-induced protein 3 (TNFAIP3) gene located on chromosome 6q23.3. The majority of disease-causing mutations in most cases of HA20 comprise single nucleotide variations, small insertions, or deletions in TNFAIP3, which result in a premature termination codon and subsequent disruption of its anti-inflammatory role. Large deletions have been reported sporadically. HA20 patients may present with a variety of autoinflammatory and autoimmune features during early childhood; however, cases with neonatal onset are rare. Here, we describe a Chinese neonate presenting with concomitant inflammatory and other syndromic manifestations caused by a 5.15 Mb interstitial deletion in chromosome 6; these deletions affect TNFAIP3. Taken together, the data extend the clinical and genetic spectra of HA20.

PMID:38183052 | PMC:PMC10770963 | DOI:10.1186/s12969-023-00947-z

J Mol Neurosci. 2024 Jan 5;74(1):2. doi: 10.1007/s12031-023-02184-1.

ABSTRACT

Primary familial brain calcification (PFBC) is a rare disorder that can manifest with a wide spectrum of motor, cognitive, and psychiatric symptoms or even remain asymptomatic. Alzheimer disease (AD) is a common condition that typically starts as a progressive amnestic disorder and progresses to major cognitive impairment. Accurately attributing an etiology to cognitive impairment can sometimes be challenging, especially when multiple pathologies with potentially overlapping symptomatology contribute to the clinical phenotype. Here, we present the case of two patients with autosomal dominant PFBC and non-monogenic AD. Cerebrospinal fluid (CSF) biomarker analysis combined with genetic testing permitted the dual diagnosis. We emphasize the importance of thoroughly characterizing the patient's phenotype at onset and during the follow-up. Particular attention is placed on psychiatric symptoms given that both patients had a history of mood disorder, a frequent condition in the general population and in neurological diseases. We also discuss and challenge the paradigm of seeking a single diagnosis explaining all symptoms, remembering the possibility of a rare disease co-occurring with a common one.

PMID:38180527 | DOI:10.1007/s12031-023-02184-1

Genome Med. 2024 Jan 4;16(1):4. doi: 10.1186/s13073-023-01276-2.

ABSTRACT

BACKGROUND: Next-generation sequencing (NGS) has significantly transformed the landscape of identifying disease-causing genes associated with genetic disorders. However, a substantial portion of sequenced patients remains undiagnosed. This may be attributed not only to the challenges posed by harder-to-detect variants, such as non-coding and structural variations but also to the existence of variants in genes not previously associated with the patient's clinical phenotype. This study introduces EvORanker, an algorithm that integrates unbiased data from 1,028 eukaryotic genomes to link mutated genes to clinical phenotypes.

METHODS: EvORanker utilizes clinical data, multi-scale phylogenetic profiling, and other omics data to prioritize disease-associated genes. It was evaluated on solved exomes and simulated genomes, compared with existing methods, and applied to 6260 knockout genes with mouse phenotypes lacking human associations. Additionally, EvORanker was made accessible as a user-friendly web tool.

RESULTS: In the analyzed exomic cohort, EvORanker accurately identified the "true" disease gene as the top candidate in 69% of cases and within the top 5 candidates in 95% of cases, consistent with results from the simulated dataset. Notably, EvORanker outperformed existing methods, particularly for poorly annotated genes. In the case of the 6260 knockout genes with mouse phenotypes, EvORanker linked 41% of these genes to observed human disease phenotypes. Furthermore, in two unsolved cases, EvORanker successfully identified DLGAP2 and LPCAT3 as disease candidates for previously uncharacterized genetic syndromes.

CONCLUSIONS: We highlight clade-based phylogenetic profiling as a powerful systematic approach for prioritizing potential disease genes. Our study showcases the efficacy of EvORanker in associating poorly annotated genes to disease phenotypes observed in patients. The EvORanker server is freely available at https://ccanavati.shinyapps.io/EvORanker/ .

PMID:38178268 | PMC:PMC10765705 | DOI:10.1186/s13073-023-01276-2

Ned Tijdschr Geneeskd. 2023 Nov 23;167:D7753.

ABSTRACT

When confronted with an unexpected clinical observation, such as a remarkable symptom in a patient with an unrelated rare disease, clinicians increasingly apply online literature search to support the observed correlation. Against a background of an exponential rise in medical publications and the well-documented problem of publication bias, the easy access to literature carries the risk of suggesting spurious correlations. The current paper expounds on this phenomenon. Queries in medical search engines often provide a number of hits, regardless of the plausibility of the correlation searched for. To quantify this, we recently performed a study involving 30.000 automated queries in PubMed using completely random search terms drawn from lists of diseases, symptoms and medications. This provided a background rate of PubMed hits. The data support that several hits by no means automatically indicate a relevant correlation, and underline need for judicious critical appraisal when searching for a correlation observed in daily practice.

PMID:38175564

Diagn Pathol. 2024 Jan 3;19(1):2. doi: 10.1186/s13000-023-01427-4.

ABSTRACT

BACKGROUND: Benign metastasizing leiomyoma (BML) is a rare disease with an unknown etiopathogenesis that mostly affects middle-aged women with uterine leiomyoma. Many metastatic nodules outside the uterus characterize the condition. The metastases are smooth muscle lesions without malignancy. Morphologically and immunohistochemically, they resemble uterine leiomyomas, indicating a shared clonal origin. The lungs are the most prevalent site for incidental metastasis detection. BML has a relatively slow progression and good prognosis, and historically, there has been a lack of established guidelines for its treatment.

CASE PRESENTATION: Herein, we report a case of BML in a patient with multiple metastases. Through extensive histological and immunohistochemical analyses, this complex case enabled not only the definitive diagnosis of BML, but also shed light on its complex etiopathogenesis.

CONCLUSION: This study presents novel histology evidence suggesting a potential causal relationship between metaplasia and the development of BML.

PMID:38172926 | PMC:PMC10765933 | DOI:10.1186/s13000-023-01427-4

BMC Ophthalmol. 2024 Jan 3;24(1):5. doi: 10.1186/s12886-023-03254-z.

ABSTRACT

BACKGROUND: Torpedo maculopathy (TM) is a rare, congenital condition characterized by an oval-shaped, chorioretinal lesion in the temporal macula of unknown etiology. To our knowledge, the longest reported follow-up of TM is 5 years. Herein we report 10 years of follow-up on two patients with TM to further characterize the long-term natural history of the condition.

CASE REPORTS: Two patients with torpedo maculopathy were examined at baseline and then again at 5 years and 10 years from baseline. Eyes were evaluated using color fundus photography, automated perimetry, fundus autofluorescence and spectral domain optical coherence tomography. Visual function of both patients remained stable throughout the observation period. In case 1, there was no evidence of change in lesion morphology over the 10 year observation period. Case 2 showed progression of cystic degeneration of the neurosensory retina within the torpedo lesion. Case 1 reported a history of supernumerary teeth and underwent gene sequence with deletion/duplication analyses of the APC gene but no clinically significant variants were detected.

CONCLUSIONS: Our findings support the position that TM is a nonprogressive condition with long-term stability of visual function. Genetic analysis of case 1 failed to detect any association with Gardner syndrome.

PMID:38172762 | DOI:10.1186/s12886-023-03254-z

Bull World Health Organ. 2024 Jan 1;102(1):22-31. doi: 10.2471/BLT.23.289731. Epub 2023 Oct 31.

ABSTRACT

OBJECTIVE: We evaluated the uptake of medicines licensed as orphan drugs by the United States Food and Drug Administration (FDA) or European Medicines Agency (EMA) into the WHO Model list of essential medicines and the WHO Model list of essential medicines for children from 1977 to 2021.

METHODS: We collated and analysed data on drug characteristics, reasons for adding or rejecting medicines, and time between regulatory approval and inclusion in the lists. We compared trends in listing orphan drugs before and after revisions to the inclusion criteria of the essential medicines lists in 2001, as well as differences in trends for listing orphan and non-orphan drugs, respectively.

FINDINGS: The proportion of orphan drugs in the essential medicines lists increased from 1.9% (4/208) in 1977 to 14.6% (70/478) in 2021. While orphan drugs for communicable diseases have remained stable over time, we observed a considerable shift towards more orphan drugs for noncommunicable diseases, particularly for cancer. The median period for inclusion in the essential medicines lists after either FDA or EMA first approval was 13.5 years (range: 1-28 years). Limited clinical evidence base and uncertainty about the magnitude of net benefit were the most frequent reasons to reject proposals to add new orphan drugs to the essential medicines lists.

CONCLUSION: Despite lack of a global definition of rare diseases, the essential medicines lists have broadened their scope to include medicines for rare conditions. However, the high costs of many listed orphan drugs pose accessibility and reimbursement challenges in resource-constrained settings.

PMID:38164340 | PMC:PMC10753278 | DOI:10.2471/BLT.23.289731

Ter Arkh. 2023 Aug 17;95(6):505-510. doi: 10.26442/00403660.2023.06.202244.

ABSTRACT

Fabry-Andersen disease is a genetically determined, progressive disease related to lysosomal storage diseases, linked to the X chromosome, characterized by impaired glycosphingolipid metabolism, due to the deficiency or absence of the enzyme α-galactosidase A. Fabry disease is a multisystem disease and is characterized by damage to vital organs - kidneys, heart, brain, with the occurrence of complications that cause an unfavorable prognosis. Autoinflammation mechanisms with signs of chronic inflammation are involved in the pathogenesis of the disease. One of the features of Fabry disease are clinical manifestations in the form of arthralgia, fever, skin lesions, which are similar to rheumatological diseases. The article presents a clinical observation of the classical type of Fabry disease with multiple organ manifestation, which required differential diagnosis with rheumatological diseases. Rheumatologists are specialists who are involved in the early diagnosis of Fabry disease, so they should have a high awareness of this sphingolipidosis.

PMID:38158971 | DOI:10.26442/00403660.2023.06.202244

Cell Rep. 2023 Dec 28;43(1):113622. doi: 10.1016/j.celrep.2023.113622. Online ahead of print.

ABSTRACT

While ATM loss of function has long been identified as the genetic cause of ataxia-telangiectasia (A-T), how it leads to selective and progressive degeneration of cerebellar Purkinje and granule neurons remains unclear. ATM expression is enriched in microglia throughout cerebellar development and adulthood. Here, we find evidence of microglial inflammation in the cerebellum of patients with A-T using single-nucleus RNA sequencing. Pseudotime analysis revealed that activation of A-T microglia preceded upregulation of apoptosis-related genes in granule and Purkinje neurons and that microglia exhibited increased neurotoxic cytokine signaling to granule and Purkinje neurons in A-T. To confirm these findings experimentally, we performed transcriptomic profiling of A-T induced pluripotent stem cell (iPSC)-derived microglia, which revealed cell-intrinsic microglial activation of cytokine production and innate immune response pathways compared to controls. Furthermore, A-T microglia co-culture with either control or A-T iPSC-derived neurons was sufficient to induce cytotoxicity. Taken together, these studies reveal that cell-intrinsic microglial activation may promote neurodegeneration in A-T.

PMID:38159274 | DOI:10.1016/j.celrep.2023.113622

Am J Med Genet A. 2023 Dec 29. doi: 10.1002/ajmg.a.63509. Online ahead of print.

ABSTRACT

Advances in bioinformatic tools paired with the ongoing accumulation of genetic knowledge and periodic reanalysis of genomic sequencing data have led to an improvement in genetic diagnostic rates. Candidate gene variants (CGVs) identified during sequencing or on reanalysis but not yet implicated in human disease or associated with a phenotypically distinct condition are often not revisited, leading to missed diagnostic opportunities. Here, we revisited 33 such CGVs from our previously published study and determined that 16 of them are indeed disease-causing (novel or phenotype expansion) since their identification. These results emphasize the need to focus on previously identified CGVs during sequencing or reanalysis and the importance of sharing that information with researchers around the world, including relevant functional analysis to establish disease causality.

PMID:38158391 | DOI:10.1002/ajmg.a.63509

J Int Med Res. 2023 Dec;51(12):3000605231220887. doi: 10.1177/03000605231220887.

ABSTRACT

Gaucher disease is a rare, autosomal recessive disorder caused by inborn errors of metabolism. Globally, more than 27 million people are born each year, and approximately 19,000 neonates are born with lysosomal storage disease. We report a rare case of Gaucher disease in an adult female patient of non-consanguineous parents in a subtropical area of Jiangxi Province, China. This area has a high prevalence of schistosomiasis. The diagnosis of this case posed a great challenge because of the possible differential diagnoses of pancytopenia with hepatomegaly and giant splenomegaly. The key component of the patient's diagnosis was her medical history in which it was documented that her brother had died of hepatocellular carcinoma of unknown origin. We diagnosed the patient through a combination of a pathological biopsy and imaging plus the patient's medical history.

PMID:38150565 | PMC:PMC10754018 | DOI:10.1177/03000605231220887

Expert Rev Clin Immunol. 2023 Dec 27. doi: 10.1080/1744666X.2023.2298354. Online ahead of print.

ABSTRACT

INTRODUCTION: Juvenile systemic sclerosis (jSSc) is an orphan disease with a prevalence of 3 in 1,000,000 children. Currently there is only one consensus treatment guideline concerning skin, pulmonary and vascular involvement for jSSc, the jSSc SHARE (Single Hub and Access point for pediatric Rheumatology in Europe) initiative, which was based on data procured up to 2014. Therefore, an update of these guidelines, with a more recent literature and expert experience, and extension of the guidance to more aspects of the disease is needed.

AREAS COVERED: Treatment options were reviewed, and opinions were provided for most facets of jSSc including general management, some which differs from adult systemic sclerosis, such as the use of corticosteroids, and specific organ involvement, such as skin, musculoskeletal, pulmonary, gastroenterology etc.

EXPERT OPINION: We are suggesting the treat to target strategy to treat early to prevent cumulative disease damage in jSSc. Conclusions are derived from both expert opinion and available literature, which is mostly based on adult systemic sclerosis (aSSc), given shared pathophysiology, extrapolation of results from aSSc studies was judged reasonable.

PMID:38149621 | DOI:10.1080/1744666X.2023.2298354

Neurol Genet. 2023 Dec 22;10(1):e200117. doi: 10.1212/NXG.0000000000200117. eCollection 2024 Feb.

ABSTRACT

OBJECTIVES: Brain-limited pathogenic somatic variants are associated with focal pediatric epilepsy, but reliance on resected brain tissue samples has limited our ability to correlate epileptiform activity with abnormal molecular pathology. We aimed to identify the pathogenic variant and map variant allele fractions (VAFs) across an abnormal region of epileptogenic brain in a patient who underwent stereoelectroencephalography (sEEG) and subsequent motor-sparing left frontal disconnection.

METHODS: We extracted genomic DNA from peripheral blood, brain tissue resected from peri-sEEG electrode regions, and microbulk brain tissue adherent to sEEG electrodes. Samples were mapped based on an anatomic relationship with the presumed seizure onset zone (SOZ). We performed deep panel sequencing of amplified and unamplified DNA to identify pathogenic variants with subsequent orthogonal validation.

RESULTS: We detect a pathogenic somatic PIK3CA variant, c.1624G>A (p.E542K), in the brain tissue samples, with VAF inversely correlated with distance from the SOZ. In addition, we identify this variant in amplified electrode-derived samples, albeit with lower VAFs.

DISCUSSION: We demonstrate regional mosaicism across epileptogenic tissue, suggesting a correlation between variant burden and SOZ. We also validate a pathogenic variant from individual amplified sEEG electrode-derived brain specimens, although further optimization of techniques is required.

PMID:38149038 | PMC:PMC10751024 | DOI:10.1212/NXG.0000000000200117

Basic Res Cardiol. 2023 Dec 26. doi: 10.1007/s00395-023-01029-7. Online ahead of print.

ABSTRACT

A deficiency of striated preferentially expressed gene (Speg), a member of the myosin light chain kinase family, results in abnormal myofibril structure and function of immature cardiomyocytes (CMs), corresponding with a dilated cardiomyopathy, heart failure and perinatal death. Mitochondrial development plays a role in cardiomyocyte maturation. Therefore, this study investigated whether Speg deficiency ( - / - ) in CMs would result in mitochondrial abnormalities. Speg wild-type and Speg-/- C57BL/6 littermate mice were utilized for assessment of mitochondrial structure by transmission electron and confocal microscopies. Speg was expressed in the first and second heart fields at embryonic (E) day 7.5, prior to the expression of mitochondrial Na+/Ca2+/Li+ exchanger (NCLX) at E8.5. Decreases in NCLX expression (E11.5) and the mitochondrial-to-nuclear DNA ratio (E13.5) were observed in Speg-/- hearts. Imaging of E18.5 Speg-/- hearts revealed abnormal mitochondrial cristae, corresponding with decreased ATP production in cells fed glucose or palmitate, increased levels of mitochondrial superoxide and depolarization of mitochondrial membrane potential. Interestingly, phosphorylated (p) PGC-1α, a key mediator of mitochondrial development, was significantly reduced in Speg-/- hearts during screening for targeted genes. Besides Z-line expression, Speg partially co-localized with PGC-1α in the sarcomeric region and was found in the same complex by co-immunoprecipitation. Overexpression of a Speg internal serine/threonine kinase domain in Speg-/- CMs promoted translocation of pPGC-1α into the nucleus, and restored ATP production that was abolished by siRNA-mediated silencing of PGC-1α. Our results demonstrate a critical role of Speg in mitochondrial development and energy metabolism in CMs, mediated in part by phosphorylation of PGC-1α.

PMID:38145999 | DOI:10.1007/s00395-023-01029-7

Int J Mol Sci. 2023 Dec 15;24(24):17496. doi: 10.3390/ijms242417496.

ABSTRACT

Leber hereditary optic neuropathy (LHON) is a rare disorder causing a sudden painless loss of visual acuity in one or both eyes, affecting young males in their second to third decade of life. The molecular background of the LHON is up to 90%, genetically defined by a point mutation in mitochondrial DNA. Recently, an autosomal recessive form of LHON (LHONAR1, arLHON) has been discovered, caused by biallelic variants in the DNAJC30 gene. This study provides the results of the DNAJC30 gene analysis in a large group of 46 Polish patients diagnosed with LHON, together with the clinical characterization of the disease. The c.152A>G (p.Tyr51Cys) substitution in the DNAJC30 gene was detected in all the patients as homozygote or compound heterozygote. Moreover, we identified one novel variant, c.293A>G, p.(Tyr98Cys), as well as two ultra-rare DNAJC30 variants: c.293A>C, p.(Tyr98Ser), identified to date only in one individual affected with LHONAR1, and c.130_131delTC (p.Ser44ValfsTer8), previously described only in two patients with Leigh syndrome. The patients presented here represent the largest group of subjects with DNAJC30 gene mutations described to date. Based on our data, the autosomal recessive form of LHON caused by DNAJC30 gene mutations is more frequent than the mitochondrial form in Polish patients. The results of our study suggest that Sanger sequencing of the single-exon DNAJC30 gene should be a method of choice applied to identify a molecular background of clinically confirmed LHON in Polish patients. This approach will help to reduce the costs of molecular testing.

PMID:38139324 | PMC:PMC10743999 | DOI:10.3390/ijms242417496

Genes (Basel). 2023 Nov 30;14(12):2162. doi: 10.3390/genes14122162.

ABSTRACT

Fibrodysplasia ossificans progressiva (FOP) is an enigmatic, ultra-rare genetic disorder characterized by progressive heterotopic ossification, wherein soft connective tissues undergo pathological transformation into bone structures. This incapacitating process severely limits patient mobility and poses formidable challenges for therapeutic intervention. Predominantly caused by missense mutations in the ACVR1 gene, this disorder has hitherto defied comprehensive mechanistic understanding and effective treatment paradigms. This write-up offers a comprehensive overview of the contemporary understanding of FOP's complex pathobiology, underscored by advances in molecular genetics and proteomic studies. We delve into targeted therapy, spanning genetic therapeutics, enzymatic and transcriptional modulation, stem cell therapies, and innovative immunotherapies. We also highlight the intricate complexities surrounding clinical trial design for ultra-rare disorders like FOP, addressing fundamental statistical limitations, ethical conundrums, and methodological advancements essential for the success of interventional studies. We advocate for the adoption of a multi-disciplinary approach that converges bench-to-bedside research, clinical expertise, and ethical considerations to tackle the challenges of ultra-rare diseases like FOP and comparable ultra-rare diseases. In essence, this manuscript serves a dual purpose: as a definitive scientific resource for ongoing and future FOP research and a call to action for innovative solutions to address methodological and ethical challenges that impede progress in the broader field of medical research into ultra-rare conditions.

PMID:38136984 | PMC:PMC10742611 | DOI:10.3390/genes14122162