In an initial clinical study, the safety and feasibility of our biosynthetic corneas was shown in the treatment of severe corneal damage as an alternative to human donor tissue. Ten patients with advanced keratoconus, or severe corneal scarring, received recombinant collagen implants and were followed for more than five years. Positive two-year follow-up data and positive four-year follow up data were reported in Science Translational Medicine (Fagerholm et al., ) and four-year follow-up data were reported in Biomaterials (Fagerholm et al., ).
Clinical evaluation and long-term follow-up to date have shown:
- Patients with biosynthetic implants had a four-year mean corrected visual acuity of 20/54 and gained on average more than five Snellen lines of vision on an eye chart.
- Nerve regrowth and touch sensitivity was closer to that of healthy corneas and significantly better in corneas with biosynthetic implants than in human donor corneas.
- Corneas with biosynthetic implants maintained a stable shape and thickness without any need for a long course of immunosuppression therapy (the patients receiving biosynthetic implants required no corticosteroid beyond 6.5 weeks post-operation).
- There has been no recruitment of inflammatory dendritic cells into the biosynthetic implant area and no episodes of rejection, in contrast to the control arm of human donor cornea transplantation, in which a rejection episode was observed.
Currently, preclinical safety testing required prior to conducting clinical trials in China are underway, and we are preparing to carry out the clinical trial required for approval at several leading clinical sites.