Experts from the UNAM developed a slow-release drug delivery method for inflammatory eye diseases. The new method consists of contact lenses that dissolve in the eye in minutes and gradually release the drug. Specifically, the researchers developed a delivery method for dexamethasone, a medication to treat certain eye conditions due to inflammation or injury, including uveitis, which could cause blindness if not treated properly. This ophthalmic film allows controlled release of the active ingredient and a better dosage for optimal recovery.

The team of scientists of the National Autonomous University of Mexico, led by José Juan Escobar Chávez, a specialist in pharmacy and pharmaceutical technology, develop this method that has the shape and dimensions of traditional contact lenses. This makes its application relatively easy; in addition, their polymers disintegrate with the ocular fluid and the waste is expelled.

Uveitis is the inflammation of the uvea (vascular layer of the eye), one of the causes of redness of the eye. It is usually accompanied by burning, itching, tearing and decreased visual acuity. It is caused by infectious agents such as bacteria, parasites, fungi and viruses; and non-infectious such as contamination or excessive use of mobile devices.

In this regard, the university stressed that in recent years have increased cases of uveitis, especially in young adults and children, due to lifestyle in combination with environmental conditions and the excessive use of electronic devices. “They spend a lot of time in front of television monitors, tablets, laptops and cell phones.”

Greater efficiency

With conventional procedures such as drops, the liquid with the active substance remains for a short time, since it is expelled almost immediately through tears and only five percent is used. However, the lenses created in the UNAM disintegrate in minutes, so the dose is fully used, avoiding the need to administer the drug frequently. Escobar Chávez said that they still intend to increase the time that the drug remains in the ocular mucosa to optimize its effectiveness.

Carlos Arturo Velázquez Tapia and Abel Esau Peña Cuevas, graduates of the degree in Pharmacy, were responsible for the design, development and characterization of biodegradable polymer lenses.

Now, together with graduate student Karla Stella Constantino, they develop laboratory eye inserts for veterinary use (for dogs), also with dexamethasone. “We have already characterized the pharmaceutical form, we will test it first in rabbits and then in dogs,” concluded Escobar Chávez.