These 2 Healthcare Stocks Are Up Over 100% in a Month. Can They Keep Climbing?

Key Points

• Shares of Nektar Therapeutics and Mineralys Therapeutics have risen sharply, and could run even further.

• Nektar is developing an experimental eczema treatment.

• Millions of patients with stubbornly high blood pressure could benefit from an experimental drug being developed by Mineralys.

• 10 stocks we like better than Nektar Therapeutics ›

Investors in the biotechnology space have been treated to a couple of big fireworks displays recently. During the month leading up to Sept. 19, shares of Nektar Therapeutics (NASDAQ: NKTR) and Mineralys Therapeutics (NASDAQ: MLYS) jumped more than 100% higher.

Just because they're already risen sharply doesn't mean they can't keep climbing. Here's a look at what drove both drugmakers' stocks through the roof, and how they could continue to outperform.

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1. Nektar Therapeutics

From Aug. 18 through the first hour of trading on Sept. 18, shares of Nektar Therapeutics shot 108% higher. Investors have been cheering for the company's lead candidate, an IL-2 pathway agonist called rezpegaldesleukin.

In a phase 2b study in patients with moderate to severe eczema, treatment with the highest dose of rezpegaldesleukin tested led to a 30% placebo-adjusted improvement. The result suggests it could compete well with Dupixent, a blockbuster eczema treatment that racked up $14.2 billion in sales for Regeneron Pharmaceuticals and its partner Sanofi last year.

In the Solo 1 trial that led to Dupixent's approval, 51% of patients taking the drug achieved 75% skin clearance, compared to 15% of those on placebo, after 16 weeks. In Nektar's latest phase 2b trial, called Rezolve-AD, its candidate helped 42% of patients achieve 75% skin clearance, compared to 17% of the placebo group.

Rezpegaldesleukin looks similar to its potential competitor at 16 weeks -- and Nektar stock is soaring because it looks like it keeps improving beyond 16 weeks. The Rezolve-AD study allowed some patients to take the candidate for 24 weeks. In this longer treatment-duration group, 62% achieved 75% skin clearance.

At recent prices, Nektar sports a $989 million market cap. On the one hand, this is low for a company that could have a blockbuster eczema treatment in mid-stage clinical trials. Then again, this wouldn't be the first time Nektar stock surged only to collapse later. The company has been around since 1990, but it has zero products to sell right now.

A phase 3 home run for rezpegaldesleukin could push Nektar Therapeutics much higher, but the company hasn't even started a phase 3 program yet. You'll want to tread lightly with this stock, even if you have a sky-high risk tolerance.

2. Mineralys Therapeutics

From the closing bell on Aug. 18 through midday on Sept. 19, shares of Mineralys Therapeutics soared by 155%, thanks largely to clinical trial results reported by a potential competitor.

Mineralys' lead candidate, lorundrostat, is an experimental hypertension treatment that targets aldosterone. Millions of Americans can't keep their blood pressure in check despite treatment with multiple medications. That means a new treatment option has blockbuster potential.

On Sept. 6, Mineralys told investors that lorundrostat lowered systolic blood pressure by a placebo-adjusted 9.1 millimeters of mercury (mmHg) in a phase 3 trial. This compares well to baxdrostat, a similar candidate from AstraZeneca that recently completed a phase 3 trial. Treatment with baxdrostat produced a placebo-adjusted 9.8 mmHg reduction for patients with hard-to-control blood pressure.

Instead of waiting around for a buyout offer from one of AstraZeneca's big pharma peers, Mineralys intends to file an application with the U.S. Food and Drug Administration (FDA) around the end of 2025 or in early 2026. AstraZeneca is operating on a similar timeline, but with far more resources.

Mineralys finished June with $325 million in cash after burning through $85.5 million in the first half of 2025. More recently, it raised $288 million in a secondary offering. Cash on hand after the latest offering should be more than enough to keep the lights on until after the FDA has a chance to review an application for lorundrostat.

At recent prices, Mineralys Therapeutics has a $3 billion market cap; that could soar further if its lead candidate becomes a commercial-stage product in 2026. With a similar competitor hot on its heels, though, its stock could also come crashing down if Mineralys finds any reason to push back its timeline. If you don't have a sky-high tolerance for risk, you'll want to watch this story play out from a safe distance.

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Cory Renauer has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Regeneron Pharmaceuticals. The Motley Fool recommends AstraZeneca Plc and Mineralys Therapeutics. The Motley Fool has a disclosure policy.