The shortage of Optisol (Bausch & Lomb), used for preserving corneal tissue and impacted by recent supply chain difficulties, won’t be as problematic as originally feared. The Eye Bank Association of America (EBAA) has arranged for importation of a substitute, EusolC, which is currently marketed in Europe but has 510k clearance from the FDA. EusolC should start arriving in the United States this week and will fill the gap until Bausch & Lomb resumes production in late May or early June, when they will manufacture twice the usual amounts for the first few weeks. Supplies of Optisol were depleted in mid-April, and the other FDA-approved corneal preservation drug, Life4C from Numedis, also stopped production in mid-April when when Numedis lost its manufacturing facility. What could have been a perfect storm situation, with the only 2 corneal storage media marketed in the United States simultaneously unavailable and a backlog of surgeries due to the pandemic, should be able to be averted.
There are enough preservation agents on hand for emergency corneal transplants, according to EBAA CEO Kevin Corcoran. Elective surgeries were shut down for approximately 6 weeks in 2020 due to COVID, leading to a backlog, but surgical volumes have gradually returned to normal as patients began to feel safe enough to schedule elective surgery. Reduced cornea donations due to COVID are not currently affecting tissue availability.
Occasional spot shortages resulting in rescheduling of some procedures may still occur because of the lack of alternative preservation media. There are no immediately available generics or compounding pharmacies that can step in to fill the gaps, as there often are with larger-volume drugs such as glaucoma drops. Optisol and Life4C are the only corneal preservation media currently available in the United States; EusolC, Kerasave, and Cornisol are available outside the United States. Final approval for Kerasave has been stalled for the last 2 years while the FDA was focused on COVID vaccines.
Another constraint contributing to potential shortages is surgeon preference for tissue no older than 7 days. The FDA has approved use of unopened preservation media with corneal tissue that has been preserved up to 14 days, and a study funded by the National Institutes of Health, the Cornea Preservation Time Study, found that the use of preserved tissue up to 11 days remains effective and safe. “If physicians would accept tissue that old, there would be less pressure on eye banks to get the tissue to the right place in 7 days,” said David Glasser, MD, a corneal specialist, professor of ophthalmology at the Johns Hopkins Wilmer Eye Institute, and Academy Secretary of Federal Affairs.
The EBAA will act as a distributor of EusolC to US eye banks until the shortage passes, ensuring that all domestic banks will have tissue available. Surgeons should be aware that they may receive tissue in unfamiliar-looking imported storage containers.