Shares of Nektar Therapeutics (NKTR -0.39%), a biopharmaceutical company, shot 90.6% higher in October, according to data from S&P Global Market Intelligence. Investors have been increasingly enthusiastic about recently announced clinical trial results for its lead candidate, rezpegaldesleukin.
In a nutshell, it looks like it could become a top-selling treatment for eczema, an itchy autoimmune disorder that affects roughly 10% of American adults.

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Nektar's experimental eczema candidate could be a top performer
Nektar Therapeutics was founded in 1990, but it doesn't have any commercial-stage drugs that generate revenue right now. For companies in this precarious position, any sign that an experimental candidate could have blockbuster potential can lead to huge gains.
Rezpegaldesleukin is the most advanced new drug candidate in Nektar's pipeline, and it took some important steps this month. At the annual European Academy of Dermatology and Venereology conference, investigators presented 16-week data from the phase 2 Rezolve-AD trial. The stock soared because it looks like rezpegaldesleukin can compete fiercely with Dupixent, a popular eczema treatment from Regeneron and Sanofi that generated $14.2 billion in sales last year.
In the Rezolve-AD trial, 42% of patients treated with the highest dose tested achieved 75% skin clearance after 16 weeks. This compares well with the results of the phase 3 Solo 2 study. In this pivotal trial that supported Dupixent's application to become an eczema drug, it helped 44% of patients achieve 75% skin clearance after 16 weeks.
Why Nektar Therapeutics could be a smart buy now
Nektar's stock price continued rising last month and into October because it also announced surprising 24-week results. After 24 weeks, 62% of eczema patients treated with Nektar's candidate achieved 75% skin clearance. It's still early, but the results suggest rezpegaldesleukin can become a blockbuster drug down the road.
Despite a big gain for the stock, Nektar's market cap was a modest $1.05 billion when the market closed on Oct. 3, 2025. That's a low valuation for a company with an experimental eczema treatment ready for phase 3 trials that appears capable of competing against the market leader. Adding some shares to a well-diversified portfolio could be a smart move.
While rezpegaldesleukin looks like a winner so far, Nektar still needs to complete a larger phase 3 trial. If an unforeseen safety issue arises, or it can't repeat the outstanding efficacy results we've already seen, the stock could fall hard. This stock is only appropriate for investors with an extremely high risk tolerance.