Pulmatrix: PTC-2105-treated mouse reaches 167 weeks
Pulmatrix's special meeting is scheduled for October 26, 2026; the proposed merger is anticipated to close shortly afterward, subject to customary conditions.
Sentiment and the balance of points
Rhea-AI Sentiment reads the wording of the document, how positive or negative its language is on a 1 to 5 scale. The balance of points shown with the takes weighs what the document actually discloses, so the two can disagree, for example when a trial that missed its main goal is described in upbeat language.
Rhea-AI Filing Summary
Pulmatrix disclosed that Eos SENOLYTIX presented preclinical mouse survival, healthspan and mechanism-of-action data for PTC-2105 and launched Team Speedy, a webpage featuring its longest-surviving mouse in a survival study and the related data. Speedy had received PTC-2105 since 80 weeks of age and was 167 weeks old, more than 6.8 months beyond the last untreated control in the study and past the roughly 155-week lifespan ceiling reported for the strain. The results are from mice; PTC-2105 has not been tested for human lifespan or approved for any indication.
Pulmatrix stockholders are scheduled to vote on the proposed merger with Eos on October 26, 2026, unless the meeting is postponed or adjourned. If completed, Eos would be a wholly owned Pulmatrix subsidiary, and the combined company’s common stock is expected to trade under the ticker MTXL. Closing is anticipated shortly after the meeting, subject to customary closing conditions.
Key Figures
Key Terms
healthspan medical
mitochondrial membrane potential medical
senescent cells medical
mitochondria-mediated apoptosis medical
sarcopenia medical
FAQ
AI-generated questions and answers. How Rhea-AI works. Not financial advice.
When will PULM stockholders vote on the proposed merger with Eos?
How does Eos study aging in mice?
AI-generated analysis. How Rhea-AI works. Not financial advice.
Filed by Pulmatrix, Inc.
Pursuant to Rule 425 under the Securities Act of 1933
and deemed filed pursuant to Rule 14a-12
of the Securities Exchange Act of 1934
Subject Companies: Pulmatrix, Inc. and Eos SENOLYTIX, Inc.
Commission File No. 333-297342
Eos SENOLYTIX Presents Late-Life Survival and Healthspan Data for Mitochondria-Targeted Geropeptide PTC-2105 at the 17th World Congress on Targeting Mitochondria, and Launches “Team Speedy” to Let the Public Follow Its Longest-Lived Mouse
| ● | In naturally aged mice treated from 80 weeks of age and followed until natural death, once-weekly PTC-2105 (25 mg/kg) significantly increased overall survival versus saline (log-rank p = 0.0142) |
| ● | “Speedy,” a PTC-2105-treated mouse now more than 167 weeks old, has outlived every saline-treated negative control in his study by more than 20% and remains active day and night |
| ● | New “Team Speedy” webpage, launching today at eossenolytix.com/team-speedy, invites the public to watch Speedy, predict how far he will go, and sign up for milestone alerts |
BERLIN and HOUSTON, Oct. 22, 2026 (GLOBE NEWSWIRE) — Eos SENOLYTIX, Inc. (“Eos” or the “Company”) a biotechnology company developing mitochondria-targeted geropeptides to improve healthspan, today presented new preclinical survival, healthspan and mechanism-of-action data for its lead candidate, PTC-2105, in an Industry Keynote Address at the 17th World Congress on Targeting Mitochondria 2026 in Berlin. The keynote, “Building on the Foundation of Four: Advancing Mitochondrial-Targeted Geropeptide Medicine,” delivered by Dr. Kevin Slawin, Founder and CEO of Eos SENOLYTIX, acknowledged the contribution of Dr. Hazel Szeto, who with Dr. Peter Schiller co-discovered the four amino acid peptide, SS-31, (“elamipretide”), the first FDA-approved therapeutic that directly targets mitochondria. Dr. Szeto opened the session, Two Perspectives on Mitochondrial Medicine, with the academic keynote; the pair then joined a panel discussion immediately afterwards.
Alongside the presentation, the Company launched Team Speedy (eossenolytix.com/team-speedy), an interactive webpage that follows “Speedy,” the longest-surviving mouse in one of its survival studies, in real time, together with the full study data behind them.
|
Join Team Speedy
Scan the code or visit eossenolytix.com/team-speedy to:
Watch Speedy ● Predict how far he goes ● Leave him a message ● Sign up for milestone alerts |
Studying aging the slow way: naturally aged mice, followed until natural death
Eos SENOLYTIX tests its compounds in naturally aged C57BL/6 mice that arrive in their state of the art Houston R&D facility at about 75 weeks of age, already late in a lifespan that rarely exceeds about 155 weeks. Rather than using accelerated-aging models, every treated and control animal is followed until it dies of natural causes, with continuous home-cage monitoring and serial measurements of body composition, strength, metabolism and cognition. The Company has completed, started or planned more than 30 such studies.
Keynote highlights
| ● | Survival. In naturally aged male mice treated from 80 weeks of age, the 25 mg/kg once-weekly PTC-2105 group showed a statistically significant increase in overall survival versus saline controls (log-rank p = 0.0142). All saline-treated controls had died by 137 weeks of age. In the 2.5 mg/kg group, overall survival did not differ significantly from saline (p = 0.59), but cancer-specific survival was improved in a competing-risks analysis (p = 0.0149). One mouse from that group, Speedy, is still alive. PTC-2105 appears to preserve and optimize late-life health, when naturally aging mice transition into a phase of “terminal decline” prior to age-related death, a transition that appears blocked by PTC-2105. Standard survival statistics, such as the log-rank test and the Cox proportional hazards model, work best when a treatment lowers the risk of death (the hazard ratio) by the same amount throughout life, so they can understate a benefit like this one that appears only later in life. |
| ● | Healthspan. Continuous 24/7 video monitoring in Olden DOME cages shows that Speedy, at 166 weeks, still had a clear day–night activity rhythm, with nighttime activity above that of untreated 100-week-old mice. At 146 weeks of age, PTC-2105-treated mice had a higher percentage of lean mass than either young (21-week) or older (84-week) untreated mice. In a separate study in aged female mice, PTC-2105 produced large dose-dependent gains in a composite functional index derived from continuous home-cage monitoring. |
| ● | Mechanism. PTC-2105 engages cardiolipin-containing membranes of the inner mitochondrial membrane and is designed to act in two ways: restoring mitochondrial membrane potential and ATP production in aging cells, and selectively triggering mitochondria-mediated apoptosis in senescent cells, which drive chronic age-related inflammation (“inflammaging”). |
| ● | Metabolism and body composition. In aged mice with diet-induced obesity, weight loss with PTC-2105 alone exceeded weight loss with the GLP-1 drug semaglutide (“SMG”) after about 30 weeks of treatment, while lean mass, uniquely in weight-loss studies, increased from baseline. |
| ● | Potentially concerning lifespan signal in SMG-treated mice. Later in life, SMG-treated mice entered an accelerated “terminal decline of aging” and died earlier than both PTC-2105-treated and saline-treated mice. In that study, the lean-mass loss that followed SMG cycling may have contributed to that earlier decline. A 180-mouse study is now under way to confirm this observation and to test whether cycling GLP-1 drugs on and off carries a lasting cost in lean mass or lifespan, and whether PTC-2105 can prevent it. |
| ● | Toward the clinic. Eos SENOLYTIX is planning first in man studies, followed by a randomized, double-blind, placebo-controlled Phase 1b study of PTC-2105 in participants aged 60 and older with sarcopenia. The 12-week study’s primary endpoint is safety; key secondary endpoints including mechanistic biomarkers, e.g. SASP and SENESCORE™, our proprietary mechanism-anchored blood measure of biological age integrating T-cell senescence, mitochondrial bioenergetics, and inflammaging. Additionally, the Company plans to measure DEXA body composition, grip strength, and other endpoints including discerning measures of muscle mass and composition, muscle strength, and physical function with a focus on measuring gerotherapeutic effects across a wide range of organ systems affected by aging-related diseases. |
| ● | MitoXcel™ Technology platform. PTC-2105 is the lead candidate from MitoXcel, a broader family of mitochondria-targeted geropeptides discovered and owned by GEROTHERAPEUTIX, Inc. (gerotherapeutix.com), with applications beyond Eos SENOLYTIX’s exclusively licensed gerotherapeutic field. MitoXcel technology is also in development as a novel cancer therapeutic by Perseus SENOLYTIX, Inc., and in consumer products by Ponce Aurora, Inc., including cosmetics, beverages and other products. These consumer products are not drugs and are not intended to diagnose, treat, cure or prevent any disease. Learn more about the platform at mitoxcel.com. |
“The goal of geroscience is not simply more years, but more healthy years,” said Dr. Slawin. “What we presented today is a body of evidence, gathered the slow way in naturally aged animals followed until their natural death, which showed that targeting mitochondrial decline and senescent cells together can improve both healthspan and lifespan in mice. Our next step is to find out whether these benefits carry over to older adults, starting in older individuals with sarcopenia.”
Meet Team Speedy
Speedy has been treated with PTC-2105 since he was 80 weeks old. At 167 weeks of age, he has now lived more than 6.8 months past the last of the untreated controls in his study and past the roughly 155-week lifespan ceiling reported for his strain.
At eossenolytix.com/team-speedy, visitors can:
| ● | Watch Speedy and see daily clips from 24/7 home-cage monitored video of activity compared with young and old untreated mice |
| ● | Explore the data behind him, including survival curves, body weight, Locomotor Composite Score, grip strength and body composition for his whole treatment group and its controls |
| ● | Predict how far Speedy will go in a just-for-fun community vote, and track upcoming milestones at 170 and 175 weeks |
| ● | Share what more healthy years would mean to them, and leave Speedy a supportive message on the fan wall |
| ● | Sign up for Speedy Alerts for new milestones, data releases and clinical updates |
“Speedy is a single animal, but he is an approachable way into the full dataset behind him,” said Dr. Slawin. “In a field with a lot of noise, we think the best way to earn attention is to let people watch the science happen and judge it for themselves.”
All data described in this release come from preclinical studies in mice. PTC-2105 is an investigational compound that has not been tested for lifespan in humans and has not been approved by the U.S. Food and Drug Administration or any other regulatory authority for any indication. Results in mice may not translate to humans.
About PTC-2105
PTC-2105 is a once-weekly, subcutaneously injected geropeptide from the MitoXcel platform. It targets the age-related decline in mitochondrial membrane potential, a hallmark of aging, through two mechanisms: enhancing mitochondrial efficiency in aging cells and selectively eliminating senescent cells through mitochondria-mediated apoptosis. Eos SENOLYTIX holds an exclusive license to develop PTC-2105 for FDA-regulated therapeutic uses outside cancer, with an initial focus on sarcopenia and sarcopenic obesity.
Proposed Merger with Pulmatrix, Inc.
As previously reported in Pulmatrix, Inc.’s (Nasdaq: PULM) (“Pulmatrix”) Current Report on Form 8-K filed with the Securities and Exchange Commission (the “SEC”) on March 27, 2026, Pulmatrix, PUOS Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of Pulmatrix (“Merger Sub”), and Eos entered into an Agreement and Plan of Merger and Reorganization, dated as of March 26, 2026 (the “Merger Agreement”), pursuant to which Merger Sub will merge with and into Eos, with Eos surviving as a wholly owned subsidiary of Pulmatrix (the “Merger”). If the Merger is completed, the business of Eos will continue as the business of the combined company, and the combined company’s common stock is expected to trade on Nasdaq under the new ticker symbol “MTXL.” Merger-associated financings are expected to support advancement of the combined company’s pipeline through key clinical milestones. In connection with the Merger, Pulmatrix filed a registration statement on Form S-4 (File No. 333-297342), with the SEC on July 9, 2026, as amended on August 3, 2026, September 4, 2026, September 17, 2026 and September 23, 2026, and declared effective by the SEC on September 25, 2026 (the “Registration Statement”), which includes a proxy statement/prospectus. Pursuant to the definitive proxy statement/prospectus filed with the SEC on September 25, 2026, as supplemented on October 7, 2026 (the “Proxy Statement/Prospectus”), Pulmatrix is asking its stockholders to vote at the special meeting of stockholders of Pulmatrix to be held on October 26, 2026 (the “Special Meeting”), unless postponed or adjourned to a later date. The Merger is anticipated to close shortly after the Special Meeting, subject to the satisfaction or waiver of the customary closing conditions set forth in the Merger Agreement.
About Eos SENOLYTIX
Eos SENOLYTIX, based in Houston, Texas, develops MitoXcel geropeptides as FDA-regulated therapeutics for obesity, sarcopenia and other age-related disorders. The Company holds an exclusive license to the MitoXcel platform from its parent company, GEROTHERAPEUTIX, for its therapeutic field. For more information, visit eossenolytix.com.
About Pulmatrix, Inc.
Pulmatrix is a biopharmaceutical company that has focused on the development of novel inhaled therapeutic products intended to prevent and treat migraine and respiratory diseases with important unmet medical needs using its patented iSPERSE™ technology. Pulmatrix’s proprietary product pipeline includes treatments for central nervous system (“CNS”) disorders such as acute migraine and serious lung diseases such as Chronic Obstructive Pulmonary Disease (“COPD”) and allergic bronchopulmonary aspergillosis (“ABPA”). Pulmatrix’s product candidates are based on its proprietary engineered dry powder delivery platform, iSPERSE™, which seeks to improve therapeutic delivery to the lungs by optimizing pharmacokinetics and reducing systemic side effects to improve patient outcomes. For more on Pulmatrix’s inhaled product candidates, please visit: https://www.pulmatrix.com/pipeline.html.
Media Contact
Sharon Kaplinsky
Email: skaplinsky@eossenolytix.com
Cell (USA): +1-646-502-6222
Forward-Looking Statements
This communication contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), Section 21E of the Securities Exchange Act of 1934, as amended, and the Private Securities Litigation Reform Act of 1995. All statements other than statements of historical fact contained in this press release are forward-looking statements. Forward-looking statements may be identified by words such as “anticipates,” “assumes,” “believes,” “can,” “could,” “estimates,” “expects,” “forecasts,” “guides,” “intends,” “is confident that,” “may,” “plans,” “seeks,” “projects,” “targets,” and “would,” and their opposites and similar expressions. Such forward-looking statements are based on the beliefs of management as well as assumptions made by and information currently available to management. Forward-looking statements in this communication include, but are not limited to, statements regarding: the Merger, including the expected timing of closing and the ability to satisfy the customary closing conditions and obtain the required approval of Pulmatrix’s stockholders; the expected timing and outcome of the Special Meeting; the expected Nasdaq listing of the combined company under the ticker symbol “MTXL”; the expected Merger-associated financings and the combined company’s ability to advance its pipeline through key clinical milestones; the potential of PTC-2105 as an approach to preserving lean mass during late-life aging and mitigating GLP-1-associated lean-mass loss; continued outcomes from the mice trials; planned future studies of the Company and anticipated results of such studies, including, but not limited to, man studies and Sarcopenia patient studies. Actual results could differ materially from those contemplated by the forward-looking statements as a result of certain factors, including but not limited to: the risk that the conditions to closing of the proposed Merger are not satisfied, including the failure to obtain stockholder approval; uncertainties as to the timing of completion of the proposed Merger; risks related to the ability to obtain necessary financings to support the combined company’s operations; the risk that preclinical results may not translate into clinical outcomes; risks related to regulatory approvals and the timing thereof; risks related to maintaining the Nasdaq listing; and general market, economic, and business conditions. Additional information concerning factors that could cause actual results to differ materially from those in the forward-looking statements is contained in the Proxy Statement/Prospectus, including under the heading “Risk Factors,” and in Pulmatrix’s Annual Report on Form 10-K for the year ended December 31, 2025 and subsequent Quarterly Reports on Form 10-Q filed with the SEC. Forward-looking statements speak only as of the date of this communication, and, except as required by law, neither Eos nor Pulmatrix undertakes any obligation to update any forward-looking statement, whether as a result of new information, future events, or otherwise.
No Offer or Solicitation
This communication and the information contained herein is not intended to and does not constitute (i) a solicitation of a proxy, consent or approval with respect to any securities or in respect of the proposed transaction or (ii) an offer to sell or the solicitation of an offer to subscribe for or buy or an invitation to purchase or subscribe for any securities pursuant to the Merger or otherwise, nor shall there be any sale, issuance or transfer of securities in any jurisdiction in contravention of applicable law. No offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act, or an exemption therefrom.
Important Additional Information about the Proposed Transaction Filed or to be Filed with the SEC
This communication is not a substitute for the Registration Statement, the Proxy Statement/Prospectus or any other document that Pulmatrix has filed or may file with the SEC in connection with the Merger. The Proxy Statement/Prospectus was first mailed to Pulmatrix’s stockholders on or about September 25, 2026. PULMATRIX URGES INVESTORS AND STOCKHOLDERS TO READ THE REGISTRATION STATEMENT, THE PROXY STATEMENT/PROSPECTUS AND ANY OTHER RELEVANT DOCUMENTS FILED OR THAT MAY BE FILED WITH THE SEC, AS WELL AS ANY AMENDMENTS OR SUPPLEMENTS TO THESE DOCUMENTS, CAREFULLY AND IN THEIR ENTIRETY BECAUSE THEY CONTAIN IMPORTANT INFORMATION ABOUT PULMATRIX, EOS, THE MERGER AND RELATED MATTERS. Investors and stockholders may obtain free copies of the Proxy Statement/Prospectus and other documents filed by Pulmatrix with the SEC through the website maintained by the SEC at www.sec.gov or from Pulmatrix’s website at https://www.pulmatrix.com/investors.html. Stockholders are urged to read the Proxy Statement/Prospectus and the other relevant materials before making any voting or investment decision with respect to the Merger. In addition, investors and stockholders should note that Pulmatrix communicates with investors and the public using its website (https://www.pulmatrix.com/investors.html/).
Participants in the Solicitation
Pulmatrix, Eos and their respective directors and executive officers may be deemed to be participants in the solicitation of proxies from Pulmatrix’s stockholders in connection with the Merger. Information about Pulmatrix’s directors and executive officers, including a description of their interests in Pulmatrix, is included in Pulmatrix’s Annual Report on Form 10-K for the year ended December 31, 2025, filed with the SEC on February 26, 2026, as amended, and, subsequent Quarterly Reports on Form 10-Q filed with the SEC, including any information incorporated therein by reference, as filed with the SEC, and other documents that may be filed from time to time with the SEC. Information about Eos’s directors and executive officers, and additional information regarding the direct and indirect interests, by security holdings or otherwise, of the participants in the solicitation, is included in the Proxy Statement/Prospectus. These documents can be obtained free of charge from the sources indicated above.
