International multicentre observational study to assess the efficacy and safety of a 0·5 mg kg-1 per day starting dose of oral corticosteroids to treat bullous pemphigoid.

BACKGROUND: European guidelines propose a 0·5 mg kg-1 per day dose of oral prednisone as initial treatment for bullous pemphigoid (BP). We assessed the safety and efficacy of this regimen depending on BP extent and general condition of the patients. METHODS: In a prospective international study, we consecutively included all patients diagnosed with BP. Patients received a 0·5 mg kg-1 per day dose of prednisone, which was then gradually tapered 15 days after disease control, with the aim of stopping prednisone or maintaining minimal treatment (0·1 mg kg-1 per day) within 6 months after the start of treatment. The two coprimary endpoints were control of disease activity at day 21 and 1-year overall survival. Disease severity was assessed according to the Bullous Pemphigoid Disease Area Index (BPDAI) score. RESULTS: In total, 198 patients were included between 2015 and 2017. The final analysis comprised 190 patients with a mean age of 80·9 (SD 9·1) years. Control of disease activity was achieved at day 21 in 119 patients [62·6%, 95% confidence interval (CI) 55·3-69.5]; 18 of 24 patients (75%, 95% CI 53·3-90·2), 75 of 110 patients (68·8%, 95% CI 59·2-77·3) and 26 of 56 patients (46.4%, 95% CI 33·0-60·3) had mild, moderate and severe BP, respectively (P = 0·0218). A total of 30 patients died during the study. The overall Kaplan-Meier 1-year survival was 82·6% (95% CI 76·3-87·4) corresponding to 90·9%, 83·0% and 80·0% rates in patients with mild, moderate and severe BP, respectively (P = 0·5). Thresholds of 49 points for BPDAI score and 70 points for Karnofsky score yielded maximal Youden index values with respect to disease control at day 21 and 1-year survival, respectively. CONCLUSIONS: A 0·5 mg kg-1 per day dose of prednisone is a valuable therapeutic option in patients with mild or moderate BP whose general condition allows them to be autonomous.

International validation of the Bullous Pemphigoid Disease Area Index severity score and calculation of cut-off values for defining mild, moderate and severe types of bullous pemphigoid.

BACKGROUND: The Bullous Pemphigoid Disease Area Index (BPDAI) score has been proposed to provide an objective measure of bullous pemphigoid (BP) activity. OBJECTIVES: The objective of this study was to calculate BPDAI cut-off values defining mild, moderate and severe BP. We also aimed to assess the interrater reliability and correlation with the number of daily new blisters, and anti-BP180 and anti-BP230 antibodies. METHODS: Severity scores were recorded by two blinded investigators. Anti-BP180 and anti-BP230 antibodies were measured using an enzyme-linked immunosorbent assay (ELISA). Cut-off values defining mild, moderate and severe subgroups were calculated based on the 25th and 75th percentiles of the BPDAI score. RESULTS: In total, 285 patients with BP were enrolled from 50 dermatology departments in Europe. Median BPDAI activity was 37·5 points (range 0-164). Cut-off values corresponding to the first and third quartiles of the BPDAI score were 20 and 57, respectively; thus, these values were used to define mild (≤ 19), moderate (≥ 20 and ≤ 56) and severe (≥ 57) BP. The median BPDAI score for patients with ≤ 10 daily new blisters was 26 [interquartile range (IQR) 17-45], and for patients with > 10 daily new blisters the median score was 55 (IQR 39-82). The BPDAI intraclass correlation coefficient measured at baseline was 0·97 and remained higher than 0·90 up to month 6. The improvement in the BPDAI score was correlated with the absolute decrease in anti-BP180 ELISA value (Spearman's rank r = 0·34, P < 0·004), but not with anti-BP230 antibodies (r = 0·17, P = 0·15). CONCLUSIONS: This study suggests cut-off values of 20-57 for BPDAI to distinguish mild, moderate and severe BP, and confirms that it is a robust tool to assess BP severity precisely.

[Factors associated with delayed diagnosis of bullous pemphigoid]. / Facteurs associés au retard diagnostique dans la pemphigoïde bulleuse.

BACKGROUND: Bullous pemphigoid (BP) is the most common form of autoimmune bullous dermatosis. The first signs of the disease comprise non-specific lesions. We conducted a retrospective study of two large series of cases of BP to identify parameters related to patients or to the disease affecting time to diagnosis (TD). METHODS: We used files from the "BP1" series retrospectively (comparison of topical and oral corticosteroids) and from the "BP2" series (comparison of two regimens of topical corticosteroids) in order to determine mean and median TD. In each series, patients were divided into two equivalent groups, i.e. patients with short TD (STD), i.e. less or equal to median, and patients with long TD (LTD), i.e. greater than median. Patient-related parameters (age, Karnofsky score, associated neurological diseases) and disease-related parameters (number of blisters and eosinophil count at diagnosis) were compared between these groups. We also investigated for any influence on TD of dermatological demography. RESULTS: Mean TD in the BP2 series was significantly shorter than in the BP1 series (61 versus 91 days, p=0.04) but the median values were similar (31 versus 36 days). There was no difference in patient age, associated neurological diseases or numbers of bullae and eosinophils between the two groups. In contrast, in the BP2 series alone, Karnofsky score was significantly lower in patients with STD (60.25%) than in patients with LTD (66%), p=0.02. Dermatological demographics had no effect on TD. CONCLUSION: Karnofsky score is the only parameter that appears to be associated with TD, with patients with worse scores having a shorter TD, probably due to better medical follow-up. Improved knowledge among general practitioners concerning the initial signs of the disease should shorten TD and accelerate the institution of appropriate therapy.

Effects of encapsulation of primidone on its oxidative metabolism in rats.

The aim of this study was to evaluate the influence of primidone (PRM) nanoencapsulation on its metabolism. Suspensions of PRM powder and PRM-loaded poly-epsilon-caprolactone nanocapsules were administered orally in the same way to rats. Primidone-loaded poly-epsilon-caprolactone nanocapsules were prepared according to the interfacial deposition technique. Free PRM suspensions were obtained by addition of PRM powder to a suspension of 0.212% carboxymethylcellulose CMC 12H in water. The dose was 20 mg/kg, n = 6, for each experiment. Urinary and faecal levels of PRM and of its three major metabolites, phenylethylmalonamide (PEMA), phenobarbital (PB), and p-hydroxyphenobarbital (p-HO-PB), were determined. Concentrations were evaluated by high-performance liquid chromatography (HPLC) according to a validated analytical method. After PRM nanocapsule administration, non-metabolised PRM urinary levels were increased compared to those observed after administration of a suspension of primidone powder (43.7+/-8.8% after PRM-loaded nanocapsule and 37.7+/-8.1% after free PRM administration). For phenylethylmalonamide, no difference was observed in urinary excretion in the two cases. For two of the oxidised metabolites, PB and p-HO-PB, excretion was delayed and shortened. The amount of these oxidised metabolites was lowered from 0.95% after free PRM administration to 0.25% after PRM-loaded nanocapsule administration. No difference was noted in non-metabolised primidone excretion in faeces. These results suggest that primidone-loaded nanocapsules could be used as a vehicle for oral primidone administration in order to minimise the phenobarbital metabolic pathway.

Primidone-loaded poly-epsilon-caprolactone nanocapsules: incorporation efficiency and in vitro release profiles.

This paper describes the preparation of primidone-loaded poly-epsilon-caprolactone nanocapsules according to the interfacial deposition technique. The colloidal suspension obtained showed a monomodal size distribution with a mean diameter ranging from 308 to 352 nm. By adjusting the process parameters, the encapsulation efficiency was about 74% with good reproducibility. Primidone release from the nanocapsules was found to be slower as compared to the oily control solution despite an important burst-effect. The release profile was not influenced by the pH of the release medium.

Simultaneous determination of primidone and its three major metabolites in rat urine by high-performance liquid chromatography using solid-phase extraction.

A new high-performance liquid chromatographic method for simultaneous determination of primidone (PRM) and of its three major metabolites, phenobarbital (PB), p-hydroxyphenobarbital (p-HO-PB) and phenylethylmalonamide (PEMA), in rat urine, was developed. After acid hydrolysis, these compounds were extracted from urine by means of a Bond Elut Certify LRC column with good clean-up. The extracts were chromatographed on a C18 reversed-phase column using isocratic elution at 40 degrees C, with UV detection at 227 nm. The limit of detection was 0.5 mg/ml for the four compounds. Good linearity (r2>0.99) was observed within the calibration ranges studied: 37.4-299.3 microg/ml for PRM, 26.4-211.2 microg/ml for PB, 12.5-100.2 microg/ml for p-HO-PB and 12.1-97.0 microg/ml for PEMA. Repeatability was in the range 3.1-6.8%. This method constitutes a useful tool for studies on the influence of various parameters on primidone metabolism.