Mass General's Stem Cell Innovation Revives Damaged Corneas
Boston, Thursday, 6 March 2025.
Mass General Hospital successfully restored damaged corneas using patients’ own stem cells, offering new hope for individuals with previously untreatable visual impairments.
Groundbreaking Clinical Trial Results
In a landmark study published on March 5, 2025, researchers at Mass Eye and Ear demonstrated remarkable success in treating corneal damage using cultivated autologous limbal epithelial cell (CALEC) transplantation. The clinical trial, involving 14 patients over 18 months, showed that CALEC was more than 90% effective at restoring the cornea’s surface [1][2]. This innovative treatment addresses unilateral limbal stem cell deficiency (USCD), a condition affecting approximately 1-5 per 10,000 people [3].
Treatment Process and Success Rates
The CALEC procedure involves harvesting stem cells from a patient’s healthy eye, expanding them in laboratory conditions over 2-3 weeks, and then surgically transplanting them to the affected eye [2]. The trial demonstrated impressive progression in recovery rates, with 50% of participants achieving complete corneal restoration at three months, increasing to 79% at twelve months, and maintaining 77% effectiveness at the 18-month mark [2][3]. Dr. Ula Jurkunas, associate director of the Cornea Service at Mass Eye and Ear, emphasized that this treatment offers hope for corneal damage previously considered untreatable [2].
Safety Profile and Future Developments
The treatment has demonstrated a strong safety profile, with only minor adverse events reported throughout the trial period. One participant experienced a bacterial infection eight months post-transplant, but no serious complications were observed in either donor or recipient eyes [2][3]. Looking ahead, researchers are planning to establish an allogeneic manufacturing process using limbal stem cells from cadaveric donor eyes, as noted by Dr. Jerome Ritz of Dana-Farber Cancer Institute [2].
Regulatory Pathway and Next Steps
While this breakthrough shows tremendous promise, the procedure is not yet available in U.S. hospitals and requires additional studies before receiving federal approval [2]. The research team is preparing for larger trials with longer follow-up periods and randomized-control designs to support FDA approval [3]. This groundbreaking work, which began nearly two decades ago through collaborations between Mass Eye and Ear, Dana-Farber, and Boston Children’s Hospital, represents a significant advancement in regenerative ophthalmology [2].