Gene therapy for recessive dystrophic epidermolysis bullosa using genetically corrected autologous keratinocytes

Patent metadata

Field	Value
Publication number	US-12559717-B2
Application number	US-202519192918-A
Country	US
Kind code	B2
Filing date	Apr 29, 2025
Priority date	Jan 4, 2016
Publication date	Feb 24, 2026
Grant date	Feb 24, 2026

Abstract

Methods are provided for the cell-based delivery of collagen VII for the treatment of Epidermolysis Bullosa and corneal erosion. The disclosure also provides a composition and a pharmaceutical composition comprises, comprise, or alternatively consist essentially of, or yet further consist of a keratinocyte sheet or a corneal cell sheet.

First claim

What is claimed is:

1 . A pharmaceutical composition for treating Recessive Dystrophic Epidermolysis Bullosa (RDEB) in a human patient, the pharmaceutical composition comprising an engineered autologous epidermal sheet, and an acellular matrix, a collagen matrix, or a biocompatible mesh;
wherein the engineered autologous epidermal sheet comprises a population of corrected and differentiated autologous keratinocytes derived from the human patient suffering from RDEB and having one or more mutations in both copies of a human collagen VII A1 (Col7A1) gene; wherein the corrected and differentiated autologous keratinocytes in the population are transduced with a retroviral vector comprising a promoter operably linked to a genetic construct encoding a functional collagen VII (COL7A1) protein, express a COL7A1 protein, and have a viral transduction efficiency (VTE)>50% and an average proviral genome copy number (PGCN) of no more than 3; and wherein the population of corrected and differentiated autologous keratinocytes is differentiated ex vivo with an epidermal sheet production medium comprising Dulbecco's Modified Eagle Medium, F12 medium, 10% fetal bovine serum, 36 ng/ml hydrocortisone, 25 μg/ml adenine, 5 μg/ml insulin, 5 μg/ml transferrin, 10 ng/ml epidermal growth factor, 30 μg/mL amikacin, 20 μg/mL vancomycin, and 2 ng/ml liothyronine.

2 . The pharmaceutical composition of claim 1 , wherein the autologous keratinocytes derived from the human patient suffering from RDEB are differentiated from stem cells ex vivo and integrated with the genetic construct encoding the functional COL7A1 protein.

3 . The pharmaceutical composition of claim 1 , wherein the biocompatible mesh comprises thermoplastic resin, polyethylene, ultra-high molecular weight polyethylene, high molecular weight polyolefin, uncoated monofilament polypropylene, polyether ether ketone, polyethylene terephthalate, polytetrafluoroethylene, expanded polytetrafluoroethylene, nylon, silicon, or any combination thereof.

4 . The pharmaceutical composition of claim 1 , wherein the biocompatible mesh comprises a synthetic or biological resorbable polymeric material selected from poly-L-lactic acid (PLLA), poly-D,L-lactic acid (PDLA), trimethylene carbonate (TMC), poly-caprolactone, poly-P-dioxanone, copolymers of lactide and glycolide, polyhydroxy-3-butyrate, biocellulose, polysaccharides, poly(DTE carbonate), or polyarylates.

5 . The pharmaceutical composition of claim 1 , wherein the acellular matrix comprises human and/or animal dermis.

6 . The pharmaceutical composition of claim 1 , wherein the pharmaceutical composition further comprises a pharmaceutically acceptable carrier.

7 . The pharmaceutical composition of claim 1 , wherein the corrected and differentiated population of autologous keratinocytes has a PGCN of less than or equal to 1.5.

8 . The pharmaceutical composition of claim 7 , wherein the average PGCN is less than 1 or 0.5.

9 . The pharmaceutical composition of claim 7 , wherein the viral transduction efficiency (VTE) of the corrected and differentiated population of autologous keratinocytes is about 70% and the proviral genome copy number (PGCN) is about 0.8.

10 . The pharmaceutical composition of claim 1 , wherein the retroviral vector comprises nucleotides 409 to 11849 of SEQ ID NO: 1.

11 . The pharmaceutical composition of claim 1 , wherein the retroviral vector is selected from Moloney murine leukemia virus (MoMLV), human immunodeficiency virus (HIV), AKR murine leukemia virus (AKR), feline immunodeficiency virus (FIV), or avian leukosis virus (ALV).

12 . The pharmaceutical composition of claim 1 , wherein the retroviral vector is a MoMLV.

13 . The pharmaceutical composition of claim 1 , wherein the retroviral vector is a MoMLV viral vector and the promoter is a MoMLV LTR promoter.

14 . The pharmaceutical composition of claim 1 , wherein the retroviral vector further comprises viral 5′ and 3′ long-terminal repeats (LTRs), and wherein each of the 5′ and 3′ LTR is selected from Moloney murine leukemia virus (MoMLV) LTR, human immunodeficiency virus (HIV)-LTR, AKR murine leukemia virus (AKR)-LTR, Feline immunodeficiency virus (FIV)-LTR, or Avian leukosis virus (ALV)-LTR.

15 . The pharmaceutical composition of claim 11 , wherein the retroviral vector further comprises viral 5′ and 3′ long-terminal repeats (LTRs), and wherein each of the 5′ and 3′ LTR is selected from Moloney murine leukemia virus (MoMLV)-LTR, human immunodeficiency virus (HIV)-LTR, AKR murine leukemia virus (AKR)-LTR, Feline immunodeficiency virus (FIV)-LTR, or Avian leukosis virus (ALV)-LTR.

16 . The pharmaceutical composition of claim 1 , wherein the engineered autologous epidermal sheet is about 25 cm 2 to about 100 cm 2 .

17 . The pharmaceutical composition of claim 1 , wherein the engineered autologous epidermal sheet is about 35 cm 2 .

Assignees

• Univ Leland Stanford Junior
• Us Gov Veterans Affairs
• The Us Gov As Represented By The Departement Of Veterans Affairs

Inventors

• Siprashvili Zurab
• Nguyen Ngon T
• Marinkovich M Peter
• Tang Jean
• Lane Alfred T
• Khavari Paul A

Classifications

• C12N2760/16043

  viral genome or elements thereof as genetic vector · CPC title

• C12N2510/00

  Genetically modified cells · CPC title

• A61K48/0091

  Purification or manufacturing processes for gene therapy compositions · CPC title

• A61K48/0075

  characterised by an aspect of the delivery route, e.g. oral, subcutaneous · CPC title

• A61K48/0058 Primary

  Nucleic acids adapted for tissue specific expression, e.g. having tissue specific promoters as part of a contruct · CPC title