Ocular Mucous Membrane Pemphigoid: The Effect of Risk Factors at Presentation on Treatment Outcomes.

PURPOSE: Analyze the influence of risk factors at presentation in the long-term immunosuppressive therapy (IMT) outcomes of ocular mucous membrane pemphigoid (OMMP). DESIGN: Retrospective multicenter study. PARTICIPANTS: Patients with OMMP seen at the Duke Eye Center, Tecnologico de Monterrey, and Hospital Clinic of Barcelona from 1990 to 2022. METHODS: Data at presentation on demographics, direct immunofluorescence, ocular findings, sites of extraocular manifestations (EOMs), and previous treatments in patients with a clinical or laboratory diagnosis of OMMP, were analyzed with multivariable analysis and Kaplan-Meier plots to identify factors associated with adverse outcomes. MAIN OUTCOME MEASURES: (1) Inflammatory control (no conjunctival inflammation in both eyes at 3 months on IMT); (2) relapse (new-onset inflammation after absolute control in either eye); (3) progression (≥ 1 cicatrizing stage progression in either eye); and (4) vision loss (≥ 2 Snellen lines). RESULTS: A total of 117 patients (234 eyes), 61% (71/117) of whom were women, with a mean age of 66.6 (SD: 12.4) years (range: 37-97 years) and median follow-up of 34 months (interquartile range: 16-66 months; range: 3-265 months), were enrolled. Inflammatory control was achieved in 57% of patients (67/117), with high-risk EOM (HR-EOM), including esophageal, nasopharyngeal, and/or genital involvement (adjusted odds ratio [aOR]: 12.51; 95% confidence interval [CI]: 2.61-59.99; P = 0.002) and corneal scarring (aOR: 3.06; 95% CI, 1.15-8.14; P = 0.025), as significant risk factors for persistent inflammation. Disease relapse, progression, and vision loss occurred in 20% of patients (23/117), 12% of patients (14/117), and 27% of patients (32/117), respectively. Baseline corneal scarring was a risk factor for relapse (adjusted hazard ratio: 4.14; 95% CI: 1.61-10.62; P = 0.003), progression (aOR: 11.46; 95% CI: 1.78-73.75; P = 0.010), and vision loss (aOR: 3.51; 95% CI: 1.35-9.10; P = 0.010). HR-EOM was associated with stage progression (aOR, 34.57; 95% CI, 6.57-181.89; P<0.001) and vision loss (aOR, 8.42; 95% CI, 2.50-28.42; P = 0.001). No significant differences were found between IMT regimes and relapse (P = 0.169). CONCLUSIONS: Ocular mucous membrane pemphigoid presenting with HR-EOMs and corneal scarring has an increased risk of stage progression and vision loss. Corneal scarring and severe inflammation at baseline were associated with an increased risk of relapse. A disease progression staging system incorporating both the HR-EOMs and corneal involvement is required to predict the visual outcome of OMMP better. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Caspase-3 promotes genetic instability and carcinogenesis.

Apoptosis is typically considered an anti-oncogenic process since caspase activation can promote the elimination of genetically unstable or damaged cells. We report that a central effector of apoptosis, caspase-3, facilitates rather than suppresses chemical- and radiation-induced genetic instability and carcinogenesis. We found that a significant fraction of mammalian cells treated with ionizing radiation can survive despite caspase-3 activation. Moreover, this sublethal activation of caspase-3 promoted persistent DNA damage and oncogenic transformation. In addition, chemically induced skin carcinogenesis was significantly reduced in mice genetically deficient in caspase-3. Furthermore, attenuation of EndoG activity significantly reduced radiation-induced DNA damage and oncogenic transformation, identifying EndoG as a downstream effector of caspase-3 in this pathway. Our findings suggest that rather than acting as a broad inhibitor of carcinogenesis, caspase-3 activation may contribute to genome instability and play a pivotal role in tumor formation following damage.

Noninvasive optical spectroscopy for identification of non-melanoma skin cancer: Pilot study.

OBJECTIVE: Optical spectroscopy offers a noninvasive alternative to biopsy as a first-line screening tool for suspicious skin lesions. This study sought to define several optical parameters across malignant and benign tissue types. STUDY DESIGN: Prospective pilot trial utilizing the Zenalux IM1 optical spectroscopy device from April 2016 to February 2017. For each skin lesion, provider pre-biopsy probability of malignancy was compared to histolopathologic diagnosis. Optical data were characterized across basal cell carcinoma (BCC; n = 9), squamous cell carcinoma (SCC; n = 5), actinic keratosis (AK; n = 4), scar tissue (n = 6), nevus (n = 2), and neurofibroma (NF; n = 1). Across all patients, agreement was determined between control measurements collected adjacent to the lesion and from the upper extremity. METHODS: Prospective single center pilot study. The optical properties of 27 cutaneous lesions were collected from 18 adult patients presenting to Otolaryngology and Dermatology clinics with suspicious skin lesions warranting biopsy. Spectroscopy measurements were recorded for each lesion: two at the lesion site, two at an adjacent site (internal control), and one at the central medial upper extremity (arm control). Variables of interest included absolute oxygenated hemoglobin (Hb), Hb saturation, total Hb concentration, and Eumelanin concentration. For each lesion, internal control averages were subtracted from lesion averages to provide delta parameter values, and lesion averages were divided by internal control averages to provide ratio parameter values. RESULTS: Mean percent difference between pre-biopsy probability of malignancy and histology was 29%, with a difference of 75% or greater seen in 5 of 25 lesions. Mean values for BCC, SCC, AK, and scar tissue varied most between extracted mean reduced scatter estimate (µa'; cm- ) delta values (BCC: -2.2 ± 3.8; SCC: -3.9 ± 2.0; AK: -3.3 ± 4.2, Scar: -1.7 ± 1.2) and total Hb (µM) ratio (BCC: 2.0 ± 3.3; SCC: 3.0 ± 1.3; AK: 1.1 ± 0.6; Scar: 1.4 ± 1.1). Agreement between local and arm controls was poor. CONCLUSION: This pilot trial utilizes optical spectroscopy as a noninvasive method for determining cutaneous lesion histology. Effect sizes observed across optical parameters for benign and malignant tissue types will guide larger prospective studies that may ultimately lead to prediction of lesional histology without need for invasive biopsy. Lasers Surg. Med. 50:246-252, 2018. © 2018 Wiley Periodicals, Inc.

Transient Receptor Potential Vanilloid 4 Ion Channel Functions as a Pruriceptor in Epidermal Keratinocytes to Evoke Histaminergic Itch.

TRPV4 ion channels function in epidermal keratinocytes and in innervating sensory neurons; however, the contribution of the channel in either cell to neurosensory function remains to be elucidated. We recently reported TRPV4 as a critical component of the keratinocyte machinery that responds to ultraviolet B (UVB) and functions critically to convert the keratinocyte into a pain-generator cell after excess UVB exposure. One key mechanism in keratinocytes was increased expression and secretion of endothelin-1, which is also a known pruritogen. Here we address the question of whether TRPV4 in skin keratinocytes functions in itch, as a particular form of "forefront" signaling in non-neural cells. Our results support this novel concept based on attenuated scratching behavior in response to histaminergic (histamine, compound 48/80, endothelin-1), not non-histaminergic (chloroquine) pruritogens in Trpv4 keratinocyte-specific and inducible knock-out mice. We demonstrate that keratinocytes rely on TRPV4 for calcium influx in response to histaminergic pruritogens. TRPV4 activation in keratinocytes evokes phosphorylation of mitogen-activated protein kinase, ERK, for histaminergic pruritogens. This finding is relevant because we observed robust anti-pruritic effects with topical applications of selective inhibitors for TRPV4 and also for MEK, the kinase upstream of ERK, suggesting that calcium influx via TRPV4 in keratinocytes leads to ERK-phosphorylation, which in turn rapidly converts the keratinocyte into an organismal itch-generator cell. In support of this concept we found that scratching behavior, evoked by direct intradermal activation of TRPV4, was critically dependent on TRPV4 expression in keratinocytes. Thus, TRPV4 functions as a pruriceptor-TRP in skin keratinocytes in histaminergic itch, a novel basic concept with translational-medical relevance.

Use of Drawing Lithography-Fabricated Polyglycolic Acid Microneedles for Transdermal Delivery of Itraconazole to a Human Basal Cell Carcinoma Model Regenerated on Mice.

Itraconazole is a triazole agent that is routinely used for treatment of nail infections and other fungal infections. Recent studies indicate that itraconazole can also inhibit the growth of basal cell carcinoma (BCC) through suppression of the Sonic Hedgehog (SHH) signaling pathway. In this study, polyglycolic acid microneedle arrays and stainless steel microneedle arrays were used for transdermal delivery of itraconazole to a human BCC model which was regenerated on mice. One-by-four arrays of 642-µm-long polyglycolic acid microneedles with sharp tips were prepared using injection molding and drawing lithography. Arrays of 85 stainless steel 800-µm-tall microneedles attached to syringes were obtained for comparison purposes. Skin grafts containing devitalized split-thickness human dermis that had been seeded with human keratinocytes transduced to express human SHH protein were sutured to the skin of immunodeficient mice. Mice with this human BCC model were treated daily for 2 weeks with itraconazole dissolved in 60% dimethylsulfoxane and 40% polyethylene glycol-400 solution; transdermal administration of the itraconazole solution was facilitated by either four 1 × 4 polyglycolic acid microneedle arrays or stainless steel microneedle arrays. The epidermal tissues treated with polyglycolic acid microneedles or stainless steel microneedles were markedly thinner than that of the control (untreated) graft tissue. These preliminary results indicate that microneedles may be used to facilitate transdermal delivery of itraconazole for localized treatment of BCC.

Definitions and outcome measures for mucous membrane pemphigoid: recommendations of an international panel of experts.

Mucous membrane pemphigoid encompasses a group of autoimmune bullous diseases with a similar phenotype characterized by subepithelial blisters, erosions, and scarring of mucous membranes, skin, or both. Although knowledge about autoimmune bullous disease is increasing, there is often a lack of clear definitions of disease, outcome measures, and therapeutic end points. With clearer definitions and outcome measures, it is possible to directly compare the results and data from various studies using meta-analyses. This consensus statement provides accurate and reproducible definitions for disease extent, activity, outcome measures, end points, and therapeutic response for mucous membrane pemphigoid and proposes a disease extent score, the Mucous Membrane Pemphigoid Disease Area Index.

Updates on the management of autoimmune blistering diseases.

Autoimmune blistering diseases are rare, but potentially debilitating cutaneous disorders characterized by varying degrees of mucosal and cutaneous bullae formation. Topical therapy is appropriate for mild and even some moderate disease activity, but systemic treatment can be considered for more extensive involvement. Corticosteroids remain the first-line systemic therapy for patients with moderate to severe bullous pemphigoid and pemphigus vulgaris. While the use of systemic steroids has dramatically reduced mortality from these two autoimmune blistering disorders, treatment is also associated with multiple side effects, especially when used long-term. Steroid sparing agents, therefore, are invaluable in inducing long-term remission while minimizing steroid associated side effects. Treatment must be tailored to the individual patient's condition, and several other factors must be carefully considered in choosing appropriate therapy: 1) diagnosis, 2) severity of the condition and body site affected, 3) presence of comorbidities, and 4) ability to tolerate systemic therapy.

Characterization of a rare IL-10-competent B-cell subset in humans that parallels mouse regulatory B10 cells.

Regulatory B cells control inflammation and autoimmunity in mice, including the recently identified IL-10-competent B10 cell subset that represents 1% to 3% of spleen B cells. In this study, a comparable IL-10-competent B10 cell subset was characterized in human blood. B10 cells were functionally identified by their ability to express cytoplasmic IL-10 after 5 hours of ex vivo stimulation, whereas progenitor B10 (B10pro) cells required 48 hours of in vitro stimulation before they acquired the ability to express IL-10. B10 and B10pro cells represented 0.6% and approximately 5% of blood B cells, respectively. Ex vivo B10 and B10pro cells were predominantly found within the CD24(hi)CD27(+) B-cell subpopulation that was able to negatively regulate monocyte cytokine production through IL-10-dependent pathways during in vitro functional assays. Blood B10 cells were present in 91 patients with rheumatoid arthritis, systemic lupus erythematosus, primary Sjögren syndrome, autoimmune vesiculobullous skin disease, or multiple sclerosis, and were expanded in some cases as occurs in mice with autoimmune disease. Mean B10 + B10pro-cell frequencies were also significantly higher in patients with autoimmune disease compared with healthy controls. The characterization of human B10 cells will facilitate their identification and the study of their regulatory activities during human disease.

Definitions and outcome measures for bullous pemphigoid: recommendations by an international panel of experts.

Our scientific knowledge of bullous pemphigoid (BP) has dramatically progressed in recent years. However, despite the availability of various therapeutic options for the treatment of inflammatory diseases, only a few multicenter controlled trials have helped to define effective therapies in BP. A major obstacle in sharing multicenter-based evidences for therapeutic efforts is the lack of generally accepted definitions for the clinical evaluation of patients with BP. Common terms and end points of BP are needed so that experts in the field can accurately measure and assess disease extent, activity, severity, and therapeutic response, and thus facilitate and advance clinical trials. These recommendations from the International Pemphigoid Committee represent 2 years of collaborative efforts to attain mutually acceptable common definitions for BP and proposes a disease extent score, the BP Disease Area Index. These items should assist in the development of consistent reporting of outcomes in future BP reports and studies.

SARS-CoV-2 infections in patients with autoimmune blistering disorders: A case series and retrospective analysis.

BACKGROUND: Autoimmune blistering disorders (AIBDs) are rare, potentially life-threatening conditions often requiring immunosuppression. Throughout the SARS-CoV-2 pandemic, infection risk and mortality in patients with AIBDs are unknown. OBJECTIVE: We report the outcomes of SARS-CoV-2 infections in patients with AIBDs and determined if patients on rituximab have an increased risk of SARS-CoV-2 infection. METHODS: We examined clinical outcomes in 10 patients with AIBDs who developed SARS-CoV-2 infections at an American hospital. We performed a retrospective analysis of 132 patients with AIBDs enrolled in a clinical trial. RESULTS: Patients with severe SARS-CoV-2 (n = 4) or death (n = 2) trended to be older. These patients had higher mortality than the national average (20% vs 1.6%). Our cohort included 52 patients with a history of rituximab treatment, 35 of whom were immunosuppressed by rituximab during the pandemic, and 45 patients never treated with rituximab. We found no difference between the rates of SARS-CoV-2 positivity in patients with AIBDs immunosuppressed by rituximab and those not on rituximab (9.1% vs 12.1%). LIMITATIONS: Testing for SARS-CoV-2 was performed on demand rather than surveillance. Overall transmission varied over time, and outcomes depended on accepted treatments. The small sample size of our cohort limits the generalizability of our results. CONCLUSION: This study suggests that rituximab does not increase the risk of SARS-CoV-2 test positivity in patients with AIBDs. However, these results should be interpreted with caution due to our relatively small sample size.

Safety, Tolerability, and Activity of ALXN1830 Targeting the Neonatal Fc Receptor in Chronic Pemphigus.

Pemphigus is a debilitating IgG-mediated autoimmune disease requiring better tolerated, more targeted, and rapid onset therapies. ALXN1830 is a humanized IgG4 antibody that blocks neonatal Fc receptor interactions with IgG. A multicenter, open-label safety and tolerability phase 1b/2 trial (NCT03075904) was conducted in North America from July 2017 to January 2019 and included patients aged ≥18 years with a confirmed diagnosis of pemphigus (vulgaris or foliaceus) and active disease. Dosing included five weekly intravenous doses of ALXN1830 (10 mg/kg) and follow-up through day 112 (study termination). Pharmacokinetics, pharmacodynamics, safety, and efficacy, as evaluated by determining the change in the median pemphigus disease area index, were determined. In this pilot study of eight patients, five weekly infusions of ALXN1830 produced a rapid improvement in the pemphigus disease area index score within 14 days of the first dose. Pemphigus disease area index improvement increased further together with reductions in IgG, circulating immune complexes of IgG, and anti-desmoglein antibodies without affecting albumin, IgM, IgA, or C-reactive protein levels. ALXN1830 was well-tolerated, with headache as the most common adverse event. This study reveals the importance of neonatal Fc receptor in the biology of pemphigus and the potential for use of ALXN1830 in pemphigus treatment.

Correlation of IgG autoantibodies against acetylcholine receptors and desmogleins in patients with pemphigus treated with steroid sparing agents or rituximab.

INTRODUCTION: Autoantibodies (autoAbs) against desmoglein-1 (DSG1) and desmoglein-3 (DSG3) have conventionally been studied and well accepted in the pathogenesis of pemphigus vulgaris (PV) and foliaceus (PF). Recent studies have suggested that non-DSG autoAbs may contribute to the pathogenesis of pemphigus, including autoAbs directed at acetylcholine receptors (AChR) and thyroid peroxidase (TPO). The purpose of this study is to retrospectively analyze PV and PF patient sera to better understand the relationship between anti-AChR and -TPO Abs to disease activity and DSG reactivity between patients treated with prednisone and steroid sparing agents (SSA; n = 22) or prednisone and rituximab (n = 21). METHODS: Patients were evaluated at 2 time points, T1 and T2, for disease activity using the Pemphigus Disease Area Index (PDAI), and sera were tested for the presence of TPO, DSG1, DSG3, muscarinic (M3) and nicotinic (n) AChR IgG autoAbs, as well as antibodies against Varicella Zoster Virus (VZV) by ELISA. RESULTS: Disease activity significantly decreased in patients from T1 to T2 (p < .0001). A significant difference was seen in IgG anti-DSG1 (p < .0001) and anti-DSG3 (p = .0049) levels when T1 was compared to T2 in both treatment groups. A significant increase was found between pemphigus patients and normal subjects with nAChR (p < .0001) at T1 but not with m3AChR, TPO or VZV Abs. No significant difference was seen between T1 and T2 values in patients with pemphigus for the non-desmoglein Abs TPO (p = .7559), M3AChR (p = .9003), nAChR (p = .5143) or VZV (p = .2454). These findings demonstrate that although an increase in IgG anti-nAChR autoAbs was found in PV and PF subjects, these Abs did not decrease with treatment. No other non-DSG Abs were increased or significantly changed over time in patients with pemphigus. This suggests that anti -AChR and -TPO Abs may not play a direct role in the pathogenesis of most patients with pemphigus, but does not rule out a role for non-DSG auto antibodies in distinct subsets of pemphigus patient.

Induction of hair follicle neogenesis with cultured mouse dermal papilla cells in de novo regenerated skin tissues.

De novo skin regeneration with human keratinocytes amplified in culture is a life-saving procedure for patients with extensive skin loss and chronic wounds. It also provides a valuable platform for gene function and therapeutic assessments. Nevertheless, tissues generated in this manner lack hair follicles that are important for skin homeostasis, barrier function, and repair. In this study, we generated skin tissues with human keratinocytes combined with dermal papilla (DP) cells isolated from mouse whisker hair. For this, cultured keratinocytes and mouse DP (mDP) cells were mixed at 10:1 ratio and seeded onto devitalized human dermal matrix derived from surgically discarded human abdominoplasty skin. After 1 week in submerged culture, the cell/matrix composites were grafted onto the skin wound beds of immunocompromised NSG.SCID mice. Histological analysis of 6-week-old skin grafts showed that tissues generated with the addition of mDP cells contained Sox2-positive dermal condensates and well-differentiated folliculoid structures that express human keratinocyte markers. These results indicate that cultured mDP cells can induce hair follicle neogenesis in the de novo regenerated skin tissues. Our method offers a new experimental system for mechanistic studies of hair follicle morphogenesis and tissue regeneration and provides insights to solving an important clinical challenge in generation of fully functional skin with a limited source of donor cells.

Interrater Reliability of Clinical Grading Measures for Cutaneous Chronic Graft-vs-Host Disease.

Importance: Cutaneous chronic graft-vs-host disease (cGVHD) is common after allogeneic hematopoietic stem cell transplant and is often associated with poor patient outcomes. A reliable and practical method for assessing disease severity and response to therapy among these patients is urgently needed. Objective: To evaluate the interrater agreement and reliability of skin-specific and range of motion (ROM) variables of the 2014 National Institutes of Health (NIH) response criteria for cGVHD and a skin sclerosis grading scale (SSG). Design, Setting, and Participants: In this observational study performed at a single tertiary academic center, 6 academic blood and marrow transplant specialists and 4 medical dermatologists examined 8 patients with diagnosed cutaneous cGVHD on July 10, 2015. The patient cohort was enriched for patients with sclerotic features. Each patient was evaluated by using the skin-specific and ROM criteria of the 2014 NIH response criteria for cGVHD and an SSG ranging from 0 to 3. Each patient was also asked to complete quality-of-life scoring instruments. Interrater agreement and reliability were estimated by calculating the Krippendorff α and Cohen κ statistics. Data were analyzed from September 29, 2015, through November 22, 2018. Main Outcomes and Measures: Estimation of interrater agreement by interclass coefficient (Krippendorff α and Cohen κ statistics) for the skin-specific and ROM components of the 2014 NIH Response Criteria for Chronic GVHD and for the SSG. Results: The median age of the patients evaluated was 54 years (range, 46-58 years). Patients were predominantly male (6 [75%]). Six of the 8 patients had a predominantly sclerotic cutaneous phenotype. Interrater agreement among our experts was acceptable for NIH skin feature score (0.68; 95% CI, 0.30-0.86) and good for NIH ROM scoring (0.80; 95% CI, 0.68-0.86). Dermatologists had acceptable agreement for NIH skin GVHD score (0.69; 95% CI, 0.25-0.82) and skin feature score (0.78; 95% CI, 0.17-0.98), good agreement in ROM grading (0.85; 95% CI, 0.69-0.90), and near perfect agreement in identifying sclerosis (0.82; 95% CI, 0.27-0.97). Conclusions and Relevance: Although dermatologists had acceptable agreement in NIH skin GVHD score and skin features score, near perfect agreement in identifying cutaneous sclerosis, better agreement in grading severity of cutaneous cGVHD, especially in the intermediate grades, appears to be needed.

A topical antioxidant solution containing vitamins C and E stabilized by ferulic acid provides protection for human skin against damage caused by ultraviolet irradiation.

BACKGROUND: Skin cancer and photoaging changes result from ultraviolet (UV)-induced oxidative stress. Topical antioxidants may protect skin from these effects. OBJECTIVE: We sought to determine whether a stable topical formulation of 15% L-ascorbic acid, 1% alpha-tocopherol, and 0.5% ferulic acid (CEFer) could protect human skin in vivo from substantial amounts of solar-simulated UV radiation. METHODS: CEFer and its vehicle were applied to separate patches of normal-appearing human skin for 4 days. Each patch was irradiated with solar-simulated UV, 2 to 10 minimal erythema doses, at 2-minimal erythema dose intervals. One day later, skin was evaluated for erythema and sunburn cells, and immunohistochemically for thymine dimers and p53. UV-induced cytokine formation, including interleukin (IL)-1alpha, IL-6, IL-8, and IL-10, and tumor necrosis factor-alpha, were evaluated by real-time polymerase chain reaction. RESULTS: CEFer provided significant and meaningful photoprotection for skin by all methods of evaluation. LIMITATIONS: The number of patients evaluated was relatively small. CONCLUSION: CEFer provided substantial UV photoprotection for skin. It is particularly effective for reducing thymine dimer mutations known to be associated with skin cancer. Its mechanism of action is different from sunscreens and would be expected to supplement the sun protection provided by sunscreens.

Comparison of rituximab and conventional adjuvant therapy for pemphigus vulgaris: A retrospective analysis.

BACKGROUND: Rituximab is a promising steroid sparing agent used in the treatment of moderate to severe pemphigus vulgaris. Its exact place in the algorithm of pemphigus treatment, vis-à-vis other, conventional adjuvant therapy (CAT) is not known. OBJECTIVE: To describe and compare disease course outcomes and morbidity among patients with moderate to severe pemphigus who received rituximab therapy (RT) in addition to prednisone and CAT, versus those who were treated with prednisone and CAT alone. METHODS: A 16-year retrospective case control study was designed with adult patients who were seen at the Duke University Dermatology Immunodermatology clinic from 1999-2015, who had a diagnosis of pemphigus vulgaris, and required prednisone and at least 1 systemic CAT. All patients had at least 6 months follow up from the initial visit. Interventions included RT, systemic CAT, and prednisone. The main outcome measured was prednisone intake. Secondary outcomes were complete remission (CR) and partial remission (PR). RESULTS: 40 patients were included in the study. All initially received prednisone and at least 1 systemic CAT. 13/40 eventually went on to receive RT, while 27/40 remained on CAT (CAT-only). Patients in the RT group, pre-RT, had a median prednisone intake of 658.57 mg/month. Rituximab treatment significantly reduced this to 177.22 mg/month (p = 0.002). Median prednisone intake of the CAT-only group was 141.33 mg/month. This was significantly less than Pre-RT (p = 0.01) and on par with Post-RT intake (p = 0.58). 54% of patients in the RT group and 64% of those in the CAT-only group achieved CR. All patients in the RT group and 96% of those in the CAT-only group achieved at least PR. CONCLUSIONS: 32.5% of our patients with moderate to severe pemphigus vulgaris failed prednisone and traditional CAT treatment and required rituximab therapy. Rituximab reduced the monthly prednisone intake in these patients by 73%. This suggests that a subset of patients with moderate to severe pemphigus may benefit from early institution of rituximab therapy. Rituximab significantly reduces the monthly prednisone requirement among CAT-resistant pemphigus vulgaris patients to levels on par with CAT-responsive patients.