Costs of UK community care for individuals with recessive dystrophic epidermolysis bullosa:Findings of the Prospective Epidermolysis Bullosa Longitudinal Evaluation Study

Background Recessive dystrophic epidermolysis bullosa (RDEB) is a rare inherited skin fragility disorder requiring multidisciplinary management. Information regarding costs of current standard treatment is scant. Objectives As part of a longitudinal natural history study, we explored the community care costs of UK patients with different forms of RDEB. Methods Fifty-nine individuals with RDEB provided detailed information on multiple facets of RDEB including disease severity scores (iscorEB, BEBS) and patient reported outcomes (quality of life evaluation in epidermolysis bullosa, iscorEB patient questionnaire). Costs data included time spent doing dressings, frequency of dressing changes, details of materials used, and paid and unpaid care. Results Overall costs of dressing materials and associated care were high in RDEB. Median annual costs across all subtypes for those using dressings (n = 51) were over £26 000. For severe RDEB (RDEB-S), median costs were almost £90 000 per annum, with a median of 18 h per week spent on dressing changes. Half of working-age adults with RDEB were unemployed and 39time or part-time paid employment, adding to indirect costs and the financial burden from RDEB on families and society. Conclusions The findings demonstrate the high costs of care of RDEB, particularly for RDEB-S. The current expense supports the drive to develop new therapies which accelerate wound healing and diminish total wound burden, thereby reducing costs of dressings and care. While costly to bring to market, these might ultimately reduce the overall cost of treatment and also the impact on individuals living with this rare disease. The data also highlight the need for adequate reimbursement for EB care which can place significant financial strain on families.<br/

Identification of Rigosertib for the Treatment of Recessive Dystrophic Epidermolysis Bullosa–Associated Squamous Cell Carcinoma

PURPOSE: Squamous cell carcinoma (SCC) of the skin is the leading cause of death in patients with the severe generalized form of the genetic disease recessive dystrophic epidermolysis bullosa (RDEB). Although emerging data are identifying why patients suffer this fatal complication, therapies for treatment of RDEB SCC are in urgent need. EXPERIMENTAL DESIGN: We previously identified polo-like kinase 1 (PLK1) as a therapeutic target in skin SCC, including RDEB SCC. Here, we undertake a screen of 6 compounds originally designated as PLK1 inhibitors, and detail the efficacy of the lead compound, the multipathway allosteric inhibitor ON-01910, for targeting RDEB SCC in vitro and in vivo. RESULTS: ON-01910 (or rigosertib) exhibited significant specificity for RDEB SCC: in culture rigosertib induced apoptosis in 10 of 10 RDEB SCC keratinocyte populations while only slowing the growth of normal primary skin cells at doses 2 orders of magnitude higher. Furthermore, rigosertib significantly inhibited the growth of two RDEB SCC in murine xenograft studies with no apparent toxicity. Mechanistically, rigosertib has been shown to inhibit multiple signaling pathways. Comparison of PLK1 siRNA with MEK inhibition, AKT inhibition, and the microtubule-disrupting agent vinblastine in RDEB SCC shows that only PLK1 reduction exhibits a similar sensitivity profile to rigosertib. CONCLUSIONS: These data support a “first in RDEB” phase II clinical trial of rigosertib to assess tumor targeting in patients with late stage, metastatic, and/or unresectable SCC

Biallelic mutations in <i>KDSR </i>disrupt ceramide synthesis and result in a spectrum of keratinization disorders associated with thrombocytopenia

Mutations in ceramide biosynthesis pathways have been implicated in a few Mendelian disorders of keratinization, although ceramides are known to have key roles in several biological processes in skin and other tissues. Using whole-exome sequencing in four probands with undiagnosed skin hyperkeratosis/ichthyosis, we identified compound heterozygosity for mutations in KDSR, encoding an enzyme in the de novo synthesis pathway of ceramides. Two individuals had hyperkeratosis confined to palms, soles, and anogenital skin, whereas the other two had more severe, generalized harlequin ichthyosis-like skin. Thrombocytopenia was present in all patients. The mutations in KDSR were associated with reduced ceramide levels in skin and impaired platelet function. KDSR enzymatic activity was variably reduced in all patients, resulting in defective acylceramide synthesis. Mutations in KDSR have recently been reported in inherited recessive forms of progressive symmetric erythrokeratoderma, but our study shows that biallelic mutations in KDSR are implicated in an extended spectrum of disorders of keratinization in which thrombocytopenia is also part of the phenotype. Mutations in KDSR cause defective ceramide biosynthesis, underscoring the importance of ceramide and sphingosine synthesis pathways in skin and platelet biology