A new target for treatment of one type of macular degeneration 

Key Takeaways

  • Researchers have determined in mice that an enzyme related to cell growth and division is a culprit in the abnormal blood vessel formation characteristic of wet AMD.
  • Targeting the enzyme with an experimental drug suppressed abnormal blood vessel growth in the animals’ retinas.

The only current treatment for the wet version of AMD, a condition characterized by blood vessel invasion in the back of the eye that causes blurred central vision, is injection into the eye of a medication that blocks the activity of a growth factor protein called VEGF. VEGF is known to prompt formation of abnormal blood vessel growth in this condition. 

“Anti-VEGF treatment has shortcomings — after two years, about half of people stop responding. And patients can develop scarring under the retina,” said Nagaraj Kerur, senior author of a study published in Biochimica et Biophysica Acta (BBA) – Molecular Basis of Disease. “There is a need for better understanding of the mechanisms behind this problem, which, to me, means newer targets need to be tested.”

Kerur and colleagues conducted a study that hints at the promise of an eventual alternative treatment option for wet AMD. The researchers determined in mice that an enzyme related to cell growth and division is a culprit in the abnormal blood vessel formation characteristic of wet AMD. Targeting the enzyme, called telomerase, with an experimental drug suppressed abnormal vascular growth in the animals’ retinas.

The experimental treatment’s effectiveness at curbing abnormal blood vessel growth in mice was similar to the current anti-VEGF treatment, Kerur said. But the researchers made an intriguing finding when testing both drugs at lower doses: Individually, a lower dose did not have much of a therapeutic effect, but a combination of both drugs at lower doses gave the best results of all. “Possibly, one goal would be using a combination therapy rather than one alone,” Kerur said. “But telomerase inhibition by itself can also be pursued independently, and that is the plan.”

This work was supported by National Institutes of Health, the Ohio Lions Eye Research Foundation and a Research to Prevent Blindness grant.

Edited by Miriam Kaplan, PhD

Source: Ohio State University, Medical Xpress, July 2, 2024; see source article