What happened

Shares of Viking Therapeutics (NASDAQ:VKTX), a clinical-stage biopharmaceutical company, took off after a handful of investment bank analysts had nice things to say about VK2809 in response to updated clinical trial results. Excitement for signs or efficacy at a lower-than-expected dosage has pushed the stock 16.8% higher on Friday.

So what 

Roughly one-third of Americans have nonalcoholic fatty liver disease (NAFLD), and the lives of perhaps 20 million members of this group are at risk due to chronic inflammation of their liver, a condition known as nonalcoholic steatohepatitis (NASH). 

Happy guy in a vest.

Image source: Getty Images.

There aren't any available treatments for NAFLD or NASH, and the first one could be a huge success. Viking released a preview of mid-stage clinical trial results that investigators will present at a medical conference a couple of weeks from now. 

The room will probably be packed as they show off data that bodes well for VK2809's safety profile. Specifically, improvements seen with a 5 mg dose appear nearly as good as 10 mg every day, and 10 mg every other day.

The median relative change in liver fat content was 54% for the low dose, and we already knew that the highest dose led to a 60% reduction. Patients in the placebo group had a 9.4% reduction from baseline, which suggests the lower dosage is good enough to do the job.

Check out the latest earnings call transcript for Viking Therapeutics.

Now what

Taking less of a drug usually reduces the risk of side effects, so it's good to know Viking can probably use 5 mg daily, instead of the larger doses. Before you get too revved up, though, it's important to point out that there were only 59 patients in this study, and they were divided into four groups.

The primary goal of the mid-stage trial everyone's so excited about wasn't treating NASH patients; it was a study with NAFLD patients who also have too much bad cholesterol floating around. The big goal was to prove a cholesterol-lowering benefit.

There's no telling what will happen when VK2809 is used to treat patients with full-blown NASH, but we do know that it's generally more difficult to elicit a response from a damaged liver than from ones that aren't under attack.

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