Histogen Inc. has found a way to harvest embryonic proteins while avoiding the controversy of embryonic stem cells and the contamination risks of animal serum. The company grows newborn fibroblasts in a bioreactor that makes the cells think they are still in an embryonic environment.
Gail Naughton, founder, chairman and CEO of Histogen, explained that fibroblasts produce different proteins and growth factors in the embryo, which is why babies who have had surgery conducted in utero are born without scars. By growing newborn fibroblasts under hypoxic conditions that mimic the embryonic state, Histogen is able to change the expression of 5,000 genes and harvest some of the embryonic proteins.
Histogen gets its fibroblasts from circumcisions, an approach that may sound familiar to those who remember Advanced Tissue Sciences Inc. ATS, also co-founded by Naughton, used newborn fibroblasts in wound healing and antiwrinkle applications, but filed for bankruptcy in 2002. (See BioWorld Today, Oct. 14, 2002.)
The problem with ATS, Naughton explained, was that the product approval and reimbursement processes "took longer . . . than anyone had anticipated."
Histogen plans to avoid those issues by developing research tools that can be marketed right away and pursuing therapeutic indications that don't require reimbursement.
For now, Histogen is using its bioreactor to produce two products: a solid product consisting of extracellular matrix proteins (ECM) and a liquid product dubbed HGEN-001 containing growth factors and wnt proteins.
Naughton said the fibroblasts begin secreting those protein products within days of being placed in the bioreactor, and large volumes can be obtained in a matter of weeks.
In the short-term, Histogen plans to market both ECM and HGEN-001 as media additives to support stem cell growth. Partnership discussions with research tool companies are under way, and Histogen hopes to launch a product by the end of this year.
At the same time, Histogen is talking to potential partners about using ECM in tissue regeneration patches for markets such as urinary incontinence, rotator cuff repair, dura mater repair and pelvic floor repair. Such uses could be pursued through a 510(k) regulatory pathway, also providing potential near-term revenues.
In the next five to six years, Histogen envisions working with partners to launch ECM products as coatings for medical implants, soft-tissue fillers for wrinkles and bulking agents for urinary incontinence or gastroesophageal reflux disease. Such uses likely would fall under the premarket approval regulatory path.
While Histogen projects those strategies could generate several hundred million dollars in revenue, the company sees an HGEN-001 therapeutic for hair growth as its long-term golden ticket.
Preclinical studies already have demonstrated that the product can increase new hair follicle creation and hair growth. Histogen plans to file an investigational new drug application by midyear and is in discussions with potential partners.
Other long-term applications for HGEN-001 could include a topical spray for lesions of the nose, mouth and throat; eye drops for cornea repair; enema formulations for ulcerative colitis or Crohn's disease; and inhalers for emphysema or lung conditions in premature infants.
In all its many planned endeavors, Histogen plans to seek partners.
"Our job is to produce the solid and liquid proteins and supply them to partners," Naughton said.
Founded in mid-2007, San Diego-based Histogen has six employees.
Naughton provided seed funding for the company but is in the process of raising a Series A, which she expects to close in March for around $3.7 million. That money would last 18 months, she said, allowing the company to expand its team, obtain two to three 510(k) approvals and begin clinical trials for HGEN-001 in hair growth.