SEATTLE, WA, October 28, 2025 – Nautilus Biotechnology, Inc. (NASDAQ: NAUT; or “Nautilus”), a company pioneering a single-molecule proteome analysis platform, today reported financial results for the third quarter ended September 30, 2025.

•Continued progress was made in processing Tau proteoform samples from collaborators in support of our goals of product validation and growing our publications. We expect to share this data at the upcoming World HUPO conference.

•Further progress was made in the development of a new broadscale assay format, which is intended to support our forthcoming commercial launch in late 2026.

•We expect to launch our early access program with Tau proteoforms in the first half of 2026.

“In Q3, Nautilus maintained disciplined execution and delivered meaningful progress across our platform, strategic collaborations, and operational initiatives—all aligned with our path toward commercialization in late 2026,” said Sujal Patel, CEO of Nautilus Biotechnology. “Our near-term focus is on the successful launch of our early access program, beginning with Tau proteoforms in the first half of 2026 and expanding to broadscale capabilities later in the year. These milestones are critical steps toward enabling customers to experience the value of our technology and advancing toward full commercial availability.”

Operating expenses were $15.5 million for the third quarter of 2025, a 19% decrease compared to $19.1 million for the corresponding prior year period. The decrease in operating expenses is attributable to operating efficiencies, lower development-related costs, and decreased salaries, related benefits and stock-based compensation.

Net loss was $13.6 million for the third quarter of 2025, as compared to the net loss of $16.4 million for the corresponding prior year period.

Cash, cash equivalents, and investments were $168.5 million as of September 30, 2025.

Nautilus will host a conference call to discuss the third quarter 2025 financial results, business developments and outlook before market open on Tuesday, October 28, 2025, at 5:30 AM Pacific Time / 8:30 AM Eastern Time. Live audio of the webcast will be available on the “Investors” section of the company website at: www.nautilus.bio.

With its corporate headquarters in Seattle, Washington and its research and development headquarters in San Carlos, California, Nautilus is a development stage life sciences company working to create a platform technology for quantifying and unlocking the complexity of the proteome. Nautilus’ mission is to transform the field of proteomics by democratizing access to the proteome and enabling fundamental advancements across human health and medicine. To learn more about Nautilus, visit www.nautilus.bio

This press release contains forward-looking statements within the meaning of federal securities laws.

Forward-looking statements in this press release include, but are not limited to, statements regarding Nautilus’ expectations regarding the company’s business operations, financial performance and results of operations; expectations regarding operating expenses and cash runway; expectations with respect to any revenue timing or projections; expectations with respect to the development required for and the timing of the launch of Nautilus’ product platform and full commercial availability; the functionality and performance of Nautilus’ product platform, its potential impact on providing proteome or proteoform access, pharmaceutical development and drug discovery, expanding research horizons, and enabling scientific explorations and discovery; expectations regarding platform specifications required by potential customers and partners and the timeline for adoption of Nautilus’ platform by researchers; and the present and future capabilities and limitations of emerging proteomics technologies. These statements are based on numerous assumptions concerning the development of Nautilus’ products, target markets, and other current and emerging proteomics technologies, and involve substantial risks, uncertainties and other factors that may cause actual results to be materially different from the information expressed or implied by these forward-looking statements. Risks and uncertainties that could materially affect the accuracy of Nautilus’ assumptions and its ability to achieve the forward-looking statements set forth in this press release include (without limitation) the following: Nautilus’ product platform is not yet commercially available and remains subject to significant scientific and technical development, which is inherently challenging and difficult to predict, particularly with respect to highly novel and complex products such as those being developed by Nautilus. Even if our development efforts are successful, our product platform will require substantial validation of its functionality and utility in life science research. In the course of Nautilus’ scientific and technical development and associated product validation and commercialization, we may experience material delays as a result of unanticipated events. We cannot provide any guarantee or assurance with respect to the outcome of our development, collaboration, and commercialization initiatives or with respect to their associated timelines. For a more detailed description of additional risks and uncertainties facing Nautilus and its development efforts, investors should refer to the information under the caption “Risk Factors” in our Annual Report on Form 10-K as well as in our Quarterly Report on Form 10-Q to be filed for the quarter ended September 30, 2025 and our other filings with the SEC. The forward-looking statements in this press release are as of the date of this press release. Except as otherwise required by applicable law, Nautilus disclaims any duty to update any forward-looking statements. You should, therefore, not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this press release.

Nautilus uses filings with the Securities and Exchange Commission, its website (www.nautilus.bio), press releases, public conference calls, public webcasts, and its social media accounts as means of disclosing material non-public information and for complying with Regulation FD. Therefore, Nautilus encourages investors, the media, and others interested in Nautilus to review the information it makes public in these locations, as such information could be deemed to be material information.

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