Functional genotype-phenotype associations in recessive dystrophic epidermolysis bullosa.

BACKGROUND: Genotype-phenotype associations in recessive dystrophic epidermolysis bullosa (RDEB) have been difficult to elucidate. OBJECTIVE: To investigate RDEB genotype-phenotype associations and explore a functional approach to genotype classification. METHODS: Clinical examination and genetic testing of RDEB subjects, including assessment of clinical disease by RDEB subtype and extent of blistering. Genotypes were evaluated according to each variant's effect on type VII collagen function per updated literature and subsequently categorized by degree of impact on VII collagen function as low-impact (splice/missense, missense/missense), medium-impact (premature termination codon [PTC]/missense, splice/splice), and high-impact (PTC/PTC, PTC/splice). Genotype-phenotype associations were investigated using Kruskal-Wallis and Fisher's exact tests, and age-adjusted regressions. RESULTS: Eighty-three participants were included. High-impact variants were associated with worse RDEB subtype and clinical disease, including increased prevalence of generalized blistering (55.6% for low-impact vs 72.7% medium-impact vs 90.4% high-impact variants, P = .002). In age-adjusted regressions, participants with high-impact variants had 40.8-fold greater odds of squamous cell carcinoma compared to low-impact variants (P = .02), and 5.7-fold greater odds of death compared to medium-impact variants (P = .05). LIMITATIONS: Cross-sectional design. CONCLUSION: Functional genotype categories may stratify RDEB severity; high-impact variants correlated with worse clinical outcomes. Further validation in larger cohorts is needed.

Practical considerations relevant to treatment with the gene therapy beremagene geperpavec-svdt for dystrophic epidermolysis bullosa.

BACKGROUND/PURPOSE: Dystrophic epidermolysis bullosa (DEB), a rare genetic skin disease caused by loss-of-function mutations in COL7A1, the gene encoding type VII collagen (COL7), is characterized by skin blistering, scarring, and extracutaneous manifestations that markedly reduce patient quality-of-life. Beremagene geperpavec-svdt ('B-VEC') is a gene therapy employing a non-integrating, replication-defective herpes simplex virus type 1 (HSV-1)-based vector encoding two copies of full-length human COL7A1 to restore COL7 protein after topical administration to DEB wounds. B-VEC was approved in the United States in 2023 as the first topical gene therapy and the first approved treatment for DEB. However, few providers have experience with use of this gene therapy. METHODS: Data was obtained through literature review and the experience of providers who participated in the B-VEC clinical study or initiated treatment after B-VEC approval. RESULTS: This review discusses the burden of disease, describes the clinical trial outcomes of B-VEC, and provides physician and patient/caregiver recommendations as a practical guide for the real-world use of B-VEC, which can be administered in-office or at the patient's home. CONCLUSIONS: By continuing to optimize the practical aspects of B-VEC administration, the focus will continue to shift to patient-centric considerations and improved patient outcomes.

Anti-NC16A IgA from Patients with Linear IgA Bullous Dermatosis Induce Neutrophil-Dependent Subepidermal Blistering in Mice.

Linear IgA bullous dermatosis (LABD) is an acquired autoimmune subepidermal blistering skin disease characterized by circulating and tissue-bound IgA autoantibodies that recognize epitopes within the hemidesmosomal protein BP180, including its NC16A domain. Histologically, LABD has long been defined by neutrophil infiltration and dermal-epidermal separation. However, the pathogenic roles of anti-NC16A IgA and neutrophils in LABD, as well as their interactions, have not been thoroughly studied. We show that passive transfer of patient-derived anti-NC16A IgA induce clinical and histologic LABD pathology in humanized NC16A mice that are reconstituted locally or systemically with human neutrophils. The lesional skin of mice exhibits significantly elevated levels of the neutrophil chemoattractants CXCL-1 and CXCL-2. Furthermore, we show significantly increased levels of the neutrophil chemoattractant IL-8 in blister fluids of patients with LABD. This study provides direct evidence that anti-NC16A IgA in patients with LABD are pathogenic and interact with neutrophils to mediate tissue injury and subepidermal blister formation. This study further corroborates the importance of neutrophil-mediated tissue injury in LABD disease physiology and establishes a clinically relevant in vivo model system that can be used to systematically dissect the immunopathogenesis of LABD.

Cell volume expansion and local contractility drive collective invasion of the basement membrane in breast cancer.

Breast cancer becomes invasive when carcinoma cells invade through the basement membrane (BM)-a nanoporous layer of matrix that physically separates the primary tumour from the stroma. Single cells can invade through nanoporous three-dimensional matrices due to protease-mediated degradation or force-mediated widening of pores via invadopodial protrusions. However, how multiple cells collectively invade through the physiological BM, as they do during breast cancer progression, remains unclear. Here we developed a three-dimensional in vitro model of collective invasion of the BM during breast cancer. We show that cells utilize both proteases and forces-but not invadopodia-to breach the BM. Forces are generated from a combination of global cell volume expansion, which stretches the BM, and local contractile forces that act in the plane of the BM to breach it, allowing invasion. These results uncover a mechanism by which cells collectively interact to overcome a critical barrier to metastasis.

Treatment With Ataluren for Wound Healing and Health Complications in a Patient With Junctional Epidermolysis Bullosa.

This case report describes an 11-year-old boy with widespread chronic wounds, frequent corneal erosions, dental caries, a tracheostomy, and failure to thrive.

Mapping the burden of severe forms of epidermolysis bullosa - Implications for patient management.

Background: The pathophysiological processes underlying the phenotypic spectrum of severe forms of epidermolysis bullosa (EB) are complex and poorly understood. Objective: To use burden mapping to explore relationships between primary pathomechanisms and secondary clinical manifestations in severe forms of EB (junctional and dystrophic EB [JEB/DEB]) and highlight strengths and weaknesses in evidence regarding the contribution of different pathways. Methods: Literature searches were performed to identify evidence regarding the pathophysiological and clinical aspects of JEB/DEB. Identified publications and clinical experience were used to construct burden maps to visually communicate plausible connections and their relative importance by subtype. Results: Our findings suggest that most of the clinical consequences of JEB/DEB may result from an abnormal state and/or faulty skin remodeling driven by a vicious cycle of delayed wound healing, predominantly mediated through inflammation. The quantity and quality of evidence varies by individual manifestations and disease subtype. Limitations: The burden maps are provisional hypotheses requiring further validation and are limited by the published evidence base and subjectivity in clinical opinion. Conclusions: Delayed wound healing appears to be a key driver of the burden of JEB/DEB. Further studies are warranted to understand the role of inflammatory mediators and accelerated wound healing in patient management.

Localized CO2 laser treatment of a recalcitrant oral ulceration in pemphigus vulgaris.

INTRODUCTION: Recalcitrant oral lesions of pemphigus vulgaris (PV), an autoimmune blistering disease, can result in significant discomfort, difficulty in eating, and maintaining oral hygiene. Increasing the dosage of systemic medications to control such localized lesions results in an increased risk of adverse effects. CASE PRESENTATION: We describe a male patient diagnosed at age 51 with PV by oral biopsy that included a direct immunofluorescence examination. After further baseline laboratory testing, he was started on prednisone and mycophenolate. These medications were slowly tapered with adjustments guided by clinical signs. Mycophenolate was replaced with intravenous immunoglobulin monthly infusions due to adverse effects about 2 years after initiation. During the 4.5-year follow-up period after diagnosis, his oral and skin lesions were well-controlled apart from minor transient flares. However, a painful ulcerated lesion on the facial gingiva between #11 and 12 was nonresponsive, even with the use of topical clobetasol in trays. A carbon dioxide (CO2 ) laser was used to vaporize the recalcitrant lesion under local anesthesia. The procedure resulted in complete healing of ulceration with no recurrence until the most recent examination, 2 years postlaser surgery. CONCLUSION: Adjunctive procedures that can facilitate a decrease in the cumulative dosage of corticosteroids and immunosuppressants have great value in the management of PV. CO2 laser vaporization is safe, with minimal morbidity and no long-term side effects. It should be considered an adjunctive treatment option for the management of recalcitrant lesions in patients with oral PV. KEY POINTS: Why is this case new information? To our knowledge, this is the second report on the use of a CO2 laser in the treatment of recalcitrant oral lesions of PV and the first report with a documented long-term resolution of the treated lesions. What are the keys to the successful management of this case? A localized recalcitrant lesion was treated with this approach. All other mucosal and cutaneous sites were well controlled on the patient's systemic medication regimen. What are the primary limitations to success in this case? This approach is only relevant for the management of recalcitrant lesions in patients whose disease activity is otherwise well controlled. The availability of specialized equipment and trained clinicians is necessary.

Trial of Beremagene Geperpavec (B-VEC) for Dystrophic Epidermolysis Bullosa.

BACKGROUND: Dystrophic epidermolysis bullosa is a rare genetic blistering skin disease caused by mutations in COL7A1, which encodes type VII collagen (C7). Beremagene geperpavec (B-VEC) is a topical investigational herpes simplex virus type 1 (HSV-1)-based gene therapy designed to restore C7 protein by delivering COL7A1. METHODS: We conducted a phase 3, double-blind, intrapatient randomized, placebo-controlled trial involving patients 6 months of age or older with genetically confirmed dystrophic epidermolysis bullosa. For each patient, a primary wound pair was selected, with the wounds matched according to size, region, and appearance. The wounds within each pair were randomly assigned in a 1:1 ratio to receive weekly application of either B-VEC or placebo for 26 weeks. The primary end point was complete wound healing of treated as compared with untreated wounds at 6 months. Secondary end points included complete wound healing at 3 months and the change from baseline to weeks 22, 24, and 26 in pain severity during changes in wound dressing, assessed with the use of a visual analogue scale (scores range from 0 to 10, with higher scores indicating greater pain). RESULTS: Primary wound pairs were exposed to B-VEC and placebo in 31 patients. At 6 months, complete wound healing occurred in 67% of the wounds exposed to B-VEC as compared with 22% of those exposed to placebo (difference, 46 percentage points; 95% confidence interval [CI], 24 to 68; P = 0.002). Complete wound healing at 3 months occurred in 71% of the wounds exposed to B-VEC as compared with 20% of those exposed to placebo (difference, 51 percentage points; 95% CI, 29 to 73; P<0.001). The mean change from baseline to week 22 in pain severity during wound-dressing changes was -0.88 with B-VEC and -0.71 with placebo (adjusted least-squares mean difference, -0.61; 95% CI, -1.10 to -0.13); similar mean changes were observed at weeks 24 and 26. Adverse events with B-VEC and placebo included pruritus and chills. CONCLUSIONS: Complete wound healing at 3 and 6 months in patients with dystrophic epidermolysis bullosa was more likely with topical administration of B-VEC than with placebo. Pruritus and mild systemic side effects were observed in patients treated with B-VEC. Longer and larger trials are warranted to determine the durability and side effects of B-VEC for this disease. (Funded by Krystal Biotech; GEM-3 ClinicalTrials.gov number, NCT04491604.).

Long-term safety and efficacy of gene-corrected autologous keratinocyte grafts for recessive dystrophic epidermolysis bullosa.

BACKGROUND: Recessive dystrophic epidermolysis bullosa (RDEB) is a rare, devastating blistering genodermatosis caused by mutations in the COL7A1 gene, which encodes for type VII collagen and is necessary for dermal-epidermal adhesion and integrity. Disease manifestations include severe and debilitating wounds, aggressive squamous cell carcinomas, and premature death; however, there are currently no approved therapies. This Phase 1/2a, open-label study evaluated the long-term efficacy and safety of gene-corrected autologous keratinocyte grafts (EB-101) for chronic RDEB wounds. METHODS: Autologous keratinocytes were harvested from participants with severe RDEB, transduced with a retrovirus containing the full-length COL7A1 gene, and grown into 5 × 7 cm (35 cm2) sheets. Gene-corrected keratinocyte sheets were then transplanted onto chronic RDEB wounds present for ≥ 12 weeks. RESULTS: Seven adult participants with severe RDEB were grafted with six sheets each (42 total sheets) onto wounds and followed for a mean of 5.9 years (range 4-8 years). Long-term improvements in wound healing and symptoms were observed. At year five, 70% (21/30) of treated sites demonstrated ≥ 50% wound healing compared to baseline by investigator global assessment. No sites with ≥ 50% wound healing were painful or pruritic, compared to 67% (6/9) of sites with < 50% wound healing (p < 0.001) at year five. Grafts were well-tolerated throughout long-term follow-up. No serious adverse events related to treatment were reported over a mean of 5.9 years of follow-up. No persistent systemic autoimmunity against type VII collagen or replication-competent retrovirus infections were identified, and no participants developed squamous cell carcinomas related to treatment during long-term follow-up. CONCLUSIONS: Treatment with EB-101 appears safe and efficacious, and produces long-term improvements in wound healing, pain, and itch for RDEB patients. Results from the Phase 3 randomized controlled trial are forthcoming. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01263379. Registered December 15, 2010. https://clinicaltrials.gov/ct2/show/NCT01263379.

In vivo topical gene therapy for recessive dystrophic epidermolysis bullosa: a phase 1 and 2 trial.

Recessive dystrophic epidermolysis bullosa (RDEB) is a lifelong genodermatosis associated with blistering, wounding, and scarring caused by mutations in COL7A1, the gene encoding the anchoring fibril component, collagen VII (C7). Here, we evaluated beremagene geperpavec (B-VEC), an engineered, non-replicating COL7A1 containing herpes simplex virus type 1 (HSV-1) vector, to treat RDEB skin. B-VEC restored C7 expression in RDEB keratinocytes, fibroblasts, RDEB mice and human RDEB xenografts. Subsequently, a randomized, placebo-controlled, phase 1 and 2 clinical trial (NCT03536143) evaluated matched wounds from nine RDEB patients receiving topical B-VEC or placebo repeatedly over 12 weeks. No grade 2 or above B-VEC-related adverse events or vector shedding or tissue-bound skin immunoreactants were noted. HSV-1 and C7 antibodies sometimes presented at baseline or increased after B-VEC treatment without an apparent impact on safety or efficacy. Primary and secondary objectives of C7 expression, anchoring fibril assembly, wound surface area reduction, duration of wound closure, and time to wound closure following B-VEC treatment were met. A patient-reported pain-severity secondary outcome was not assessed given the small proportion of wounds treated. A global assessment secondary endpoint was not pursued due to redundancy with regard to other endpoints. These studies show that B-VEC is an easily administered, safely tolerated, topical molecular corrective therapy promoting wound healing in patients with RDEB.

Patient-reported outcomes and quality of life in dominant dystrophic epidermolysis bullosa: A global cross-sectional survey.

INTRODUCTION: Dystrophic epidermolysis bullosa is a debilitating skin condition, without curative treatment. Previous research has focused on the recessive variant, which is known to cause severe disease. Limited work focusing on the clinical manifestations and outcomes of dominant dystrophic epidermolysis bullosa is found (DDEB). METHODS: Analysis of an online survey of 42 DDEB patients. RESULTS: Self-reported severity of disease did not correlate with size of the wound or number of dressing changes, but did correlate with severity of pain reported in the last 12 months (3.4 mild vs 6.8 severe disease, P = 0.0002). Patients with severe DDEB also reported more severe internal disease symptoms, such as difficulty swallowing (62.5%, P = 0.01) and greater analgesic use during dressing changes (4.4% mild vs 81.3% severe, P = <0.001). DISCUSSION: Patient perception of disease severity in DDEB appears to be most impacted by pain, presence of chronic open wounds, difficulty swallowing, difficulty walking, and anal strictures. As research on DDEB increases, future studies focused on these symptoms might be the most impactful for DDEB patients. However, distinguishing DDEB from other subtypes remains a challenge.

A systematic literature review of the disease burden in patients with recessive dystrophic epidermolysis bullosa.

BACKGROUND/OBJECTIVE: Recessive dystrophic epidermolysis bullosa (RDEB) is a genetic collagen disorder characterized by skin fragility leading to blistering, wounds, and scarring. There are currently no approved curative therapies. The objective of this manuscript is to provide a comprehensive literature review of the disease burden caused by RDEB. METHODS: A systematic literature review was conducted in MEDLINE and Embase in accordance with PRISMA guidelines. Observational and interventional studies on the economic, clinical, or humanistic burden of RDEB were included. RESULTS: Sixty-five studies were included in the review. Patients had considerable wound burden, with 60% reporting wounds covering more than 30% of their body. Increases in pain and itch were seen with larger wound size. Chronic wounds were larger and more painful than recurrent wounds. Commonly reported symptoms and complications included lesions and blistering, anemia, nail dystrophy and loss, milia, infections, musculoskeletal contractures, strictures or stenoses, constipation, malnutrition/nutritional problems, pseudosyndactyly, ocular manifestations, and dental caries. Many patients underwent esophageal dilation (29-74%; median dilations, 2-6) and gastrostomy tube placement (8-58%). In the severely affected population, risk of squamous cell carcinoma (SCC) was 76% and mortality from SCC reached 84% by age 40. Patients with RDEB experienced worsened quality of life (QOL), decreased functioning and social activities, and increased pain and itch when compared to other EB subtypes, other skin diseases, and the general population. Families of patients reported experiencing high rates of burden including financial burden (50-54%) and negative impact on private life (79%). Direct medical costs were high, though reported in few studies; annual payer-borne total medical costs in Ireland were $84,534 and annual patient-borne medical costs in Korea were $7392. Estimated annual US costs for wound dressings ranged from $4000 to $245,000. Patients spent considerable time changing dressings: often daily (13-54% of patients) with up to three hours per change (15-40%). CONCLUSION: Patients with RDEB and their families/caregivers experience significant economic, humanistic, and clinical burden. Further research is needed to better understand the costs of disease, how the burden of disease changes over the patient lifetime and to better characterize QOL impact, and how RDEB compares with other chronic, debilitating disorders.

Clinical characteristics associated with increased wound size in patients with recessive dystrophic epidermolysis bullosa.

As more therapeutic clinical trials focus on treatment of individual wounds in patients with recessive dystrophic epidermolysis bullosa, it has become crucial to understand the baseline clinical characteristics of these wounds. To investigate these features, we administered an RDEB-specific wound survey. Forty participants reported on location, size, pain, infection frequency, wound type, and duration of 189 wounds; a subset of 22 participants reported on pruritus in 63 wounds. Increased wound size was significantly associated with increased pain, increased pruritus, longer wound duration, increased infection frequency, and patients with mutations resulting in truncated type VII collagen.

QR-313, an Antisense Oligonucleotide, Shows Therapeutic Efficacy for Treatment of Dominant and Recessive Dystrophic Epidermolysis Bullosa: A Preclinical Study.

Dystrophic epidermolysis bullosa (DEB) is a blistering skin disease caused by mutations in the gene COL7A1 encoding collagen VII. DEB can be inherited as recessive DEB (RDEB) or dominant DEB (DDEB) and is associated with a high wound burden. Perpetual cycles of wounding and healing drive fibrosis in DDEB and RDEB, as well as the formation of a tumor-permissive microenvironment. Prolonging wound-free episodes by improving the quality of wound healing would therefore confer substantial benefit for individuals with DEB. The collagenous domain of collagen VII is encoded by 82 in-frame exons, which makes splice-modulation therapies attractive for DEB. Indeed, antisense oligonucleotide-based exon skipping has shown promise for RDEB. However, the suitability of antisense oligonucleotides for treatment of DDEB remains unexplored. Here, we developed QR-313, a clinically applicable, potent antisense oligonucleotide specifically targeting exon 73. We show the feasibility of topical delivery of QR-313 in a carbomer-composed gel for treatment of wounds to restore collagen VII abundance in human RDEB skin. Our data reveal that QR-313 also shows direct benefit for DDEB caused by exon 73 mutations. Thus, the same topically applied therapeutic could be used to improve the wound healing quality in RDEB and DDEB.

Patient-reported outcomes and quality of life in recessive dystrophic epidermolysis bullosa: A global cross-sectional survey.

BACKGROUND: A spectrum of skin disease severity exists in patients with recessive dystrophic epidermolysis bullosa (RDEB). OBJECTIVE: To characterize the patient-reported outcomes and quality of life (QOL) in patients with RDEB. METHODS: A cross-sectional study of patients with RDEB surveyed through the global EBCare Registry. Patient-reported outcomes included skin disease severity, wound characteristics, pain, itch, extracutaneous symptoms, and medications. QOL was measured by using the validated Quality of Life in Epidermolysis Bullosa instrument. RESULTS: A total of 85 patients with RDEB reported 1226 wounds (937 recurrent wounds and 289 chronic open wounds). Overall skin disease severity was self-reported as mild (26%; 22/83), moderate (48%; 40/83), or severe (25%; 21/83). Worsening skin disease severity was significantly associated with larger wounds, increased opiate use, anemia, gastrostomy tube use, infections, osteoporosis, and squamous cell carcinoma. Larger wound size was associated with worse quality of life scores. LIMITATIONS: All data were self-reported from an online epidermolysis bullosa patient registry. CONCLUSIONS: This study shows a significant correlation between larger wound size with worsening skin disease severity and quality of life in participants with RDEB. Worsening skin disease severity significantly correlated with key clinical manifestations. These results show that patients with RDEB are able to self-report their skin disease severity and wounds.

Cells from discarded dressings differentiate chronic from acute wounds in patients with Epidermolysis Bullosa.

Impaired wound healing complicates a wide range of diseases and represents a major cost to healthcare systems. Here we describe the use of discarded wound dressings as a novel, cost effective, accessible, and non-invasive method of isolating viable human cells present at the site of skin wounds. By analyzing 133 discarded wound dressings from 51 patients with the inherited skin-blistering disease epidermolysis bullosa (EB), we show that large numbers of cells, often in excess of 100 million per day, continually infiltrate wound dressings. We show, that the method is able to differentiate chronic from acute wounds, identifying significant increases in granulocytes in chronic wounds, and we show that patients with the junctional form of EB have significantly more cells infiltrating their wounds compared with patients with recessive dystrophic EB. Finally, we identify subsets of granulocytes and T lymphocytes present in all wounds paving the way for single cell profiling of innate and adaptive immune cells with relevance to wound pathologies. In summary, our study delineates findings in EB that have potential relevance for all chronic wounds, and presents a method of cellular isolation that has wide reaching clinical application.

Epidermolysis bullosa.

Epidermolysis bullosa (EB) is an inherited, heterogeneous group of rare genetic dermatoses characterized by mucocutaneous fragility and blister formation, inducible by often minimal trauma. A broad phenotypic spectrum has been described, with potentially severe extracutaneous manifestations, morbidity and mortality. Over 30 subtypes are recognized, grouped into four major categories, based predominantly on the plane of cleavage within the skin and reflecting the underlying molecular abnormality: EB simplex, junctional EB, dystrophic EB and Kindler EB. The study of EB has led to seminal advances in our understanding of cutaneous biology. To date, pathogenetic mutations in 16 distinct genes have been implicated in EB, encoding proteins influencing cellular integrity and adhesion. Precise diagnosis is reliant on correlating clinical, electron microscopic and immunohistological features with mutational analyses. In the absence of curative treatment, multidisciplinary care is targeted towards minimizing the risk of blister formation, wound care, symptom relief and specific complications, the most feared of which - and also the leading cause of mortality - is squamous cell carcinoma. Preclinical advances in cell-based, protein replacement and gene therapies are paving the way for clinical successes with gene correction, raising hopes amongst patients and clinicians worldwide.