The compound PTC124 helps "rescue" faulty proteins that lead to illness and in University of Alabama tests PTC124 restored to normal function up to 29 percent of the cases of abnormal cystic-fibrosis protein.

The study builds in research published in the journal Nature last year, which showed PTC124 restored up to 25 percent of the missing or abnormal protein function in mice with Duchenne muscular dystrophy.

"Our study shows strong preclinical evidence that PTC124 is capable of suppressing 'nonsense mutations' that cause cystic fibrosis," lead author David Bedwell said in a statement. "We think this provides strong evidence for clinical trials with PTC124 in cystic-fibrosis patients with this kind of mutation."

A gene that carries a nonsense mutation produces a shortened or faulty protein that degrades in the body and the absence of that protein is what leads to disease, Bedwell explained.

The findings are published online ahead of print in the journal Proceedings of the National Academy of Sciences.