Our Platform 

Our proprietary autologous fibroblast technology is the foundation for creating personalized gene therapies for diseases of the skin and connective tissue.

The Science of Autologous Fibroblasts

Fibroblasts are the basis of Castle Creek Biosciences’ personalized gene therapy platform because they are the most common cell in skin and connective tissue and are responsible for synthesizing extracellular matrix proteins, including collagen, that provide structure and support.

science of autologous fibroblasts

Fibroblasts—the most common cells in the body—provide an ideal foundation for Castle Creek Biosciences’ personalized gene therapies:



Fibroblasts are present in all skin and connective tissue.

Readily Sourced from Skin

Fibroblasts can be isolated from the skin and grown in culture. The ability to genetically modify fibroblasts has been well documented in scientific literature.

Functionally Critical

Fibroblasts synthesize the structural framework of tissue.

Ideal Delivery Vehicle

Fibroblasts have unique capabilities for localized (vs. systemic) delivery to gene targets in the skin and connective tissue.

Our entire fibroblast platform is done autologously. This approach allows us to avoid many of the rejection concerns presented with allogeneic cells and results in a higher likelihood of efficacy.”

— John Maslowski, Chief Executive Officer

Personalized Gene Therapy Approach

Castle Creek Biosciences’ autologous fibroblast technology uses our patented manufacturing process, which involves collecting small skin biopsies from patients, isolating cells and expanding them in culture, transducing the fibroblast cells with an integrative lentiviral vector to express a targeted protein, followed by continued expansion of the gene-modified cells in culture. In this manner, each patient is treated with cells that were cultivated from his or her own dermal tissue (i.e., autologous). 

Fibrocell-personalized-biologics-approach (1)

Validated In-House, Commercial-Scale Manufacturing Capabilities

Castle Creek Biosciences’ existing cGMP cell therapy manufacturing facility in Exton, PA has been designated as the clinical and commercial production site for FCX-007 and FCX-013

  • ~13,000 square foot facility includes cleanroom manufacturing, cryogenic storage, QC laboratories, and shipping/receiving areas
  • Manufacture of FCX-007 and FCX-013 served by multiple segregated production zones
  • Sufficient FCX-007 cGMP vector available to supply remaining clinical trials, and discussions in process with secondary producer for commercial production
  • Multiple site inspections by FDA, including all reviews necessary for production process approval

Validated systems and processes from previously approved therapy are being applied to new gene-modified cell therapy production programs, including:

  • Quality systems
  • Customer service designed for autologous manufacturing: Product ordering and tracking
  • Tracking and traceability
  • Inventory management
  • Internal raw material testing program
  • Validation Master Plan