New Delhi, May 28 (IANS) An inexpensive, long-approved HIV drug can improve vision in patients with a blinding complication of diabetes more effectively, according to preliminary results of a clinical trial.

The drug, lamivudine, could represent an important new option for millions of patients with diabetic macular edema (DME) — a condition affecting about one in 14 people with diabetes. It causes fluid to build up in the retina of the eye and affects vision.

As the drug is taken orally it potentially offers patients an alternative to monthly injections directly into their eyes, said the researchers from the University of Virginia in the US.

“The mechanism of action of lamivudine is also different from that of existing treatments, so we could also develop combination therapies,” said researcher Jayakrishna Ambati, from UVA Health’s Center for Advanced Vision Science.

The researchers explained that lamivudine is effective against DME because it blocks the activity of inflammasomes — important agents of our immune systems. Inflammasomes normally act as sensors of infections, but they have also been implicated in the development of DME.

For the study, published in the journal Med, the researchers enrolled two dozen adults with DME in a small randomised clinical trial.

Participants were randomly assigned to receive either lamivudine or a harmless placebo, in addition to injections of the drug bevacizumab into their eyes starting after four weeks.

Participants who received lamivudine showed significant vision improvements even before their first eye injections. Their ability to read letters on an eye chart improved by 9.8 letters (about 2 lines on the eye chart) at four weeks, while the participants receiving a placebo saw their ability decrease by 1.8 letters.

A month after the bevacizumab injections, the lamivudine recipients had improved by a whopping 16.9 letters (more than 3 lines on the eye chart), while the placebo group, receiving bevacizumab alone, had increased by only 5.3.

The results suggest that lamivudine may work both alone and in conjunction with bevacizumab injections, though larger studies will be needed to bear that out, the researchers said.

Lamivudine alone could be life-changing for patients in many areas of the world with limited access to specialty doctors or who are unable to afford or travel to monthly eye appointments, Ambati said, while calling for more trials of lamivudine with larger numbers of patients.

–IANS

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