What happened

Shares of Applied Therapeutics (NASDAQ:APLT) are up 29% at 12:38 p.m. EST after the biotech reported positive data from a phase 2 clinical trial of AT-007 in galactosemia patients.

So what

People with galactosemia can't properly process a sugar called galactose, which is found in food and also made by the body. The disorder results in the buildup of galactitol, which causes a range of issues, from complications in the central nervous system to cataracts in patients' eyes.

At the highest dose tested, AT-007 reduced plasma galactitol by 45% to 54%, while placebo had no substantial effect on galactitol levels. The difference was statistically significant.

Investors will have to wait until April to see the full data when Applied Therapeutics plans to present the results at the Society for Inherited Metabolic Disorders Annual Meeting.

Scientist in a lab injecting something into a test tube, which bottles of  liquid on shelves surrounding him.

Image source: Getty Images.

Now what

While it was only a phase 2 study, Applied Therapeutics thinks the clinical trial is enough to gain Food and Drug Administration approval, given the rarity of the disease, lack of treatments, and the substantial reduction in galactitol. The biotech is looking to file for approval in the second half of this year, setting up an approval next year.

Applied Therapeutics also plans to start a pediatric study this year, which will be important for getting patients on the drug early and maximizing the potential market, which the company estimates to be 2,800 U.S. patients. If AT-007 can reduce complications, it should lengthen a patient's life expectancy, which would increase the treatable population.

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