What Happened to Viking Therapeutics in 2025, And Is it a Buy for 2026?

Investors in biotechnology company Viking Therapeutics (NASDAQ: VKTX) had a rollercoaster ride in 2025, driven by clinical trial data, or rather, the perception of the clinical trial data. Let's take a brief look at what happened and how the stock is shaping up for 2026.

Viking Therapeutics' main drug candidate

The narrative around the company is dominated by its lead pipeline drug, VK2735. It's a Dual GLP-1/GIP agonist in development for diabetes and, more importantly from a financial perspective, obesity. It's set to compete with well-known blockbuster weight-loss drugs, Novo Nordisk's Wegovy (semaglutide) and Eli Lilly's Zepbound (tirzepatide).

VK2735 is being developed in both subcutaneous (under the skin) and oral forms. The oral version is especially appealing because many patients prefer pills over injections, pills can be stored at room temperature, and they are easier to take.

What happened in 2025

As you can see in the chart, something big happened in August, and it wasn't good news: the top-line results from a Phase 2 VENTURE trial of oral VK2735 were disappointing. There was nothing wrong with efficacy, with up to 12.2% weight loss at 13 weeks. However, the market questioned the safety and tolerability data, with a 20% discontinuation rate in the treatment group due to adverse events.

There's always a concern about oral medications as they can be problematic for the digestive system. Indeed, the most common reason for discontinuation was gastrointestinal adverse events.

Image source: Getty Images.

The second half recovery

After the initial disappointment, the stock recovered as Viking investors started to focus on the company's potential. There are several reasons to be optimistic.

First, the oral VK2735 trial (VENTURE) may have had overly high expectations because the Phase 1 trial demonstrated exemplary tolerability.

Second, the VENTURE trial had an aggressive titration rate and only lasted 13 weeks – the treatment group may not have had time to adjust. Moreover, note that the treatment group had a 20% discontinuation rate due to an adverse event, while the placebo group had a 13% discontinuation rate. This may suggest that the trialists' cohort had certain challenging characteristics.

Third, Viking has completed enrollment of patients in a trial testing the oral form as a maintenance dose after an initial subcutaneous dose of VK2735.

Fourth, VK2735 is also promising in its subcutaneous form. The company has completed patient enrollment in the 78-week Phase 3 VANQUISH-1 trial for obesity, and management expects to complete enrollment in the Phase 3 VANQUISH-2 trial for diabetes in early 2026.

Image source: Getty Images.

Where next for Viking Therapeutics in 2026

Given that Novo Nordisk and Pfizer both bid for obesity drug company Metsera (Pfizer won), it's fair to say there's significant interest in this class of drugs. Moreover, Viking has a $3.9 billion market cap, and Wall Street analysts believe it currently has $587 million in net cash . It might be an attractive candidate for a larger pharmaceutical company to buy. Not least, larger pharmaceutical companies tend to have a better track record in clinical trials than smaller pharmaceutical companies. That might entice a larger company to invest in Viking's pipeline, led by VK2735.

Lee Samaha has no position in any of the stocks mentioned. The Motley Fool recommends Novo Nordisk and Viking Therapeutics. The Motley Fool has a disclosure policy.