Nektar Therapeutics (NKTR) told investors its REZOLVE-AA trial followed stated eligibility criteria and protocol standards. Executives repeatedly described the study’s enrollment safeguards and expressed optimism ahead of topline data. But a recently filed lawsuit alleges those assurances left out a critical problem.
Meet Samuel – Your Personal Investing Prophet
- Start a conversation with TipRanks’ trusted, data-backed investment intelligence
- Ask Samuel about stocks, your portfolio, or the market and get instant, personalized insights in seconds
Investors who suffered losses on Nektar Therapeutics stock are taking a closer look at a newly filed lawsuit that alleges the company misled the public about the integrity of a key clinical trial, only for the truth to surface in a single damaging disclosure that sent shares tumbling.
Nektar Therapeutics is facing a federal securities lawsuit filed on March 6, 2026, in the United States District Court for the Northern District of California. The complaint, captioned Schramke v. Nektar Therapeutics et al., alleges that the company and certain of its top executives made materially false and misleading statements about its Phase 2b REZOLVE-AA clinical trial throughout a class period spanning February 26, 2025 to December 15, 2025, inclusive. When the alleged truth emerged on December 16, 2025, the company’s stock dropped $4.14 per share, or approximately 7.77%, closing at $49.16 that day. Investors who purchased or otherwise acquired Nektar securities during the class period may have legal options available to them.
Nektar Therapeutics and Its Lead Drug Program
Nektar Therapeutics is a Delaware corporation headquartered at 455 Mission Bay Boulevard South in San Francisco, California, with its common stock traded on the Nasdaq Capital Market under the ticker symbol NKTR. The company describes itself as a biopharmaceutical company focused on discovering and developing therapies designed to selectively modulate the immune system to treat autoimmune disorders. Its lead product candidate is rezpegaldesleukin, also referred to as REZPEG or NKTR-358, which is described in the complaint as a novel, first-in-class regulatory T cell stimulator being developed for the treatment of conditions including alopecia areata.
In March 2024, Nektar initiated its Phase 2b REZOLVE-AA trial, which was designed to evaluate rezpegaldesleukin in approximately ninety patients with severe-to-very severe alopecia areata who had not previously been treated with a Janus kinase inhibitor or another biologic. The trial’s enrollment criteria included a diagnosis of severe-to-very severe alopecia areata as measured using the Severity of Alopecia Tool score at both screening and randomization, along with exclusion of patients who had experienced an unstable course of the condition over the prior six months or who had inadequate washout of prior treatments within eight weeks.
What the Lawsuit Alleges Against Nektar
The complaint alleges that throughout the class period, Nektar and its senior executives made materially false and misleading statements assuring investors that enrollment in the REZOLVE-AA trial had followed applicable instructions and protocol standards. According to the lawsuit, Defendants failed to disclose that enrollment had not in fact followed those standards, that this failure was likely to significantly and negatively impact the trial’s results, and that the trial’s integrity and prospects were therefore overstated. The plaintiff contends that these omissions and misstatements artificially inflated the price of Nektar securities throughout the class period, causing investors to purchase shares at prices that did not reflect the true state of the trial.
Investors who purchased Nektar securities during the class period may wish to learn more about the allegations and explore their legal options.
What Company Executives Said During the Class Period
The complaint details a series of specific statements made by Nektar’s executives during the class period that the plaintiff alleges were false or misleading. On the February 26, 2025 press release announcing completed enrollment, Nektar stated that its enrollment criteria included a SALT score diagnosis at both screening and randomization, that patients with an unstable course of alopecia areata over the prior six months were excluded, and that patients with diffuse or other forms of alopecia were also excluded.
On a March 12, 2025 earnings call, Chief Executive Officer Howard W. Robin stated that the company has “unique operational features” in its studies “designed to minimize clinical operational risk,” while Chief Research and Development Officer Jonathan Zalevsky stated that patients in the trial “had to present with severe-to-very-severe disease” at a defined SALT score range “for at least six months in order to be eligible for inclusion.” Zalevsky reiterated nearly identical language on the May 8, 2025 earnings call, while Robin highlighted the REZOLVE-AA trial on the November 6, 2025 earnings call by calling the company “optimistic” about results. On the same November 6 call, Zalevsky again recited the enrollment eligibility criteria, emphasizing that patient eligibility was determined using the SALT score at both screening and randomization and that patients with an unstable disease course over the prior six months were excluded.
The Disclosure That Moved the Stock
The alleged corrective disclosure occurred on December 16, 2025, when Nektar issued a pre-market press release announcing topline results from the 36-week induction treatment period of the REZOLVE-AA trial. The press release disclosed that the trial’s primary endpoint narrowly missed statistical significance, reporting mean percent SALT reductions of 28.2% and 30.3% for the two treatment arms versus 11.2% for placebo, with p-values of 0.186 and 0.121, respectively, neither of which achieved statistical significance.
Critically, Nektar attributed the failure to reach statistical significance to the inclusion of four patients who the company acknowledged should not have been eligible to participate in the trial. The company disclosed that when those four patients with major study eligibility violations were excluded, both rezpegaldesleukin treatment arms did meet statistical significance on the primary endpoint. On a conference call held the same day, Nektar’s Chief Medical Officer elaborated that two of the four ineligible patients had unstable alopecia areata with their initial disease diagnosed less than six months before randomization, and that the remaining two patients had begun treatment before completing the required eight-week washout period for prior alopecia areata medications. Following these disclosures, Nektar’s stock fell $4.14 per share, or 7.77%, on December 16, 2025.
Why Nektar Investors Are Paying Attention
The lawsuit centers on a narrow but consequential allegation: that ineligible patients were enrolled in Nektar’s flagship clinical trial in violation of the trial’s own protocol standards, and that company executives continued to publicly assure investors of proper enrollment throughout the class period without disclosing this problem. According to the complaint, Nektar attributed the trial’s failure to reach statistical significance on its primary endpoint to the inclusion of four patients who should not have been eligible to participate, and analysts cited that issue as a reason for the December 16, 2025 stock decline.
The complaint further notes that during the class period, Defendant Robin sold 46,986 shares of Nektar common stock for proceeds of nearly $1 million, and that the company conducted a public offering in July 2025 that raised approximately $115 million at $23.50 per share. The lawsuit also points to executive bonuses tied in part to maintaining enrollment timelines for the REZOLVE-AA trial, arguing that this gave the Individual Defendants both the motive and the knowledge to be highly attentive to enrollment compliance.
The Legal Framework Behind the Case
The lawsuit brings claims under two provisions of the Securities Exchange Act of 1934. The first is Section 10(b) and Rule 10b-5 promulgated thereunder, which prohibit fraudulent or misleading statements and omissions in connection with the purchase or sale of securities; the plaintiff alleges that all named defendants violated these provisions by making false and misleading public statements about trial enrollment integrity throughout the class period. The second is Section 20(a), which imposes liability on individuals who control a company that has committed a primary securities law violation; the plaintiff alleges that Defendants Robin, Gardiner, and Zalevsky are liable as controlling persons of Nektar.
Investors who purchased Nektar securities between February 26, 2025 and December 15, 2025 and suffered losses may want to review their rights under the federal securities laws.
About Levi & Korsinsky, LLP
Levi & Korsinsky, LLP is a nationally recognized securities litigation firm representing investors in complex shareholder actions. The firm has extensive expertise and a team of over 70 employees to serve our clients. Attorney advertising. Prior results do not guarantee similar outcomes.
Disclaimer: This article is provided for informational purposes only and does not constitute legal advice. No attorney-client relationship is created by reading this article. Past results do not guarantee similar outcomes.