Polyclonal Regulatory T Cells (PolyTregs) for Pemphigus

Inclusion Criteria: * Ability to provide informed consent; * Diagnosis of Pemphigus Vulgaris (PV) or Pemphigus Foliaceus (PF), defined by H\&E staining (e.g., Haemotoxylin and Eosin) and direct immunofluorescence staining of skin biopsy at any time prior to enrollment; * Pemphigus treated with systemic corticosteroids within the 2 years prior to screening (historic or current), or treated with rituximab ≥ 12 months prior to screening; * Presence of: * anti-Dsg3 antibodies (\>20.0 U/ml) at screening visit consistent with diagnosis of pemphigus vulgaris or, * anti-Dsg1 antibodies (\>20.0 U/ml) at screening visit consistent with diagnosis of pemphigus foliaceus. * Active of PV or PF as defined by Pemphigus Disease Area Index (PDAI) overall activity score 3-10 at screening visit, and PDAI overall activity score 1-12 at baseline visit; * Positive test for Epstein-Barr Virus (EBV) antibody; * Adequate venous access to support draw of 400 ml whole blood and infusion of investigational therapy; and * An absolute Treg count of ≥ 42 cells/μL within 6 weeks prior to whole blood collection at Week -2 (i.e., 2 weeks prior to planned PolyTreg Infusion). Exclusion Criteria: * Initiation of systemic corticosteroid therapy, prednisone dose \> 25 mg/d (or equivalent) or change in prednisone dose within 4 weeks prior to screening; * Addition of a new medication, or change in the dose of any background medication used to treat any aspect of pemphigus within the timeframes listed below. S…