Castle Creek Acquires Fibrocell, Now Leading Development of FCX-007 Gene Therapy for RDEB

Castle Creek Pharmaceutical recently acquired Fibrocell Science and is now leading the development of treatments for epidermolysis bullosa (EB), including the investigational gene therapy FCX-007 for the treatment of recessive dystrophic epidermolysis bullosa (RDEB).

The companies had previously established a partnership to develop FCX-007.

“Our organizations have a shared commitment to delivering new treatment options to underserved communities such as EB patients and their families who have no approved therapies,” Greg Wujek, CEO of Castle Creek, said in a press release. “The addition of this late stage gene therapy will allow us to be the leader in rare genetic dermatology and additional genetic diseases as well.”

FCX-007 is a cell-based therapy that genetically modifies a patient’s own dermal fibroblasts — a type of skin cells — to produce healthy copies of type VII collagen (COL7). The modified cells are then injected back into the patient.

Collagen helps to bind skin layers and provide proper skin structure and resistance. COL7 is defective in RDEB, making the skin more fragile with frequent blistering.

FCX-007 is delivered to blisters and wounds, allowing the healthy COL7 protein to help hold the skin layers together. FCX-007 lowers the risk of side effects with this local administration, and avoids immune reactions by using the patient’s own fibroblasts.

FCX-007 previously received regenerative medicine advanced therapy, orphan drug, rare pediatric disease, and fast track designations by the U.S. Food and Drug Administration (FDA).

The safety and effectiveness of FCX-007 in RDEB is being tested in an ongoing Phase 1/2 clinical trial (NCT02810951). Phase 1 results in four adults with RDEB suggested that FCX-007 is well-tolerated and heals all treated wounds by more than half in just four weeks. Phase 2, for patients ages 7 and older, is underway.  The study is expected to conclude in December 2033.

A Phase 3 trial (NCT04213261), not yet enrolling, will further assess whether FCX-007 improves wound healing in 20 RDEB patients. More information on contacts and locations can be found here.

Up to three wounds in each participant will be treated with FCX-007, while a corresponding wound will remain untreated. Two doses of FCX-007 will be administered four weeks apart. The primary outcome of the study is change in surface area of the wound over 12 weeks. Patients can then participate in a 15-year follow-up study for safety.

Castle Creek will also continue research on CCP-020, its investigational ointment treatment for EB simplex (EBS) and other forms of the disorder. CCP-020 contains diacerein, a small molecule with strong anti-inflammatory properties that is used to treat joint and skin inflammation.

Previous evidence indicated that diacerein blocks the production of pro-inflammatory molecules, including interleukin-1beta.

Topical application of CCP-020 is expected to suppress the inflammatory response associated with EBS, strengthening skin tissue and healing blisters. The FDA previously granted fast track, rare pediatric disease, and orphan drug designations to CCP-020 for the treatment of EBS.

A previous Phase 2 study assessing CCP-020 once daily for four weeks showed a 60% reduction in skin blistering in EBS patients given the CCP-020 cream, compared to a 15% decrease in the control group. The potential treatment was well-tolerated, with none of the side effects associated with the treatment or involving the treatment area.

A Phase 1 trial (NCT03472287) of CCP-020 in EB patients 6 months and older to assess the safety and pharmacokinetics (the study of how a compound is absorbed, distributed, metabolized, and excreted in the body) is underway in the U.S. and Europe.

In addition, the long-term safety and tolerability of CCP-020 is being assessed in an international, multicenter Phase 2b trial (NCT03389308), which recruited approximately 80 participants with EBS who had previously completed other studies of CCP-020.