Biosynthetic corneas made of collagen are almost as good as the real thing, according to a 10-patient study in the August issue of Science Translational Medicine. Biosynthetic corneas can even help regenerate and repair damaged ocular tissues.
In this phase I clinical study, the researchers attempted to induce regeneration of damaged corneal tissue in 10 patients (nine with keratoconus and one with a midstromal scar) by implanting the synthetically cross-linked collagen prosthetic, which is similar in composition to the natural extracellular matrix of the human cornea.
At two-year follow-up, all 10 biosynthetic implants remained stable. They caused no major complications, no prolonged inflammatory responses, no signs of rejection or fluctuations in intraocular pressure. Furthermore, no patients required the use of long-term steroids, which is often needed following conventional corneal transplantation procedures.
Most significantly, the researchers noted that cells and nerves from the patients’ remaining corneal tissue had grown into the implant, which resulted in complete, stable reepithelialization.
Additionally, all 10 patients experienced restoration of healthy tear film levels, and six patients demonstrated improved visual acuity from preoperative baseline values.
“This study is important because it is the first to show that an artificially fabricated cornea can integrate with the human eye and stimulate regeneration,” said lead author May Griffith, M.D., senior scientist at the Ottawa Hospital Research Institute, professor at the University of Ottawa, and director of the Integrative Regenerative Medicine Centre at Linköping University in Sweden.
The researchers say the biosynthetic cornea might be used for other sight-threatening conditions that require transplantation.
Fagerholm P, Lagali NS, Merrett K, et al. A biosynthetic alternative to human donor tissue for inducing corneal regeneration: 24-month follow-up of a phase 1 clinical study. Sci Transl Med. 2010 Aug 25;2(46):46ra61.