Metsera Stock Price, News & Analysis
Company Description
Metsera, Inc. (formerly NASDAQ: MTSR) was a clinical-stage biopharmaceutical company focused on developing the next generation of medicines for obesity and cardiometabolic and metabolic diseases. According to company disclosures, Metsera advanced a broad portfolio of oral and injectable incretin, non-incretin and combination therapies designed to address multiple therapeutic targets in a rapidly evolving weight loss treatment landscape. Metsera was founded in 2022 and was based in New York City.
On November 13, 2025, Pfizer Inc. completed its previously announced acquisition of Metsera, Inc., as reported in Metsera’s Form 8-K dated November 13, 2025. The transaction was structured as a merger of Mayfair Merger Sub, Inc., a wholly owned subsidiary of Pfizer, with and into Metsera, with Metsera surviving as a wholly owned subsidiary of Pfizer. In connection with the closing, each issued and outstanding share of Metsera common stock (other than specified excluded shares and appraisal shares) was converted into the right to receive a cash payment of $65.60 per share plus one contractual contingent value right (CVR) per share, subject to the terms and conditions of the Contingent Value Rights Agreement described in the Form 8-K.
Following the closing of the merger, Metsera’s common stock ceased trading on the Nasdaq Global Select Market. As disclosed in the November 13, 2025 Form 8-K, Metsera notified Nasdaq of the completion of the merger and requested that Nasdaq suspend trading, withdraw the listing of Metsera common stock, and file a Form 25 to delist the shares and deregister them under Section 12(b) of the Securities Exchange Act of 1934. Metsera also indicated its intention to file a Form 15 to deregister its common stock under Section 12(g) of the Exchange Act and suspend its reporting obligations under Section 15(d). As a result, MTSR now represents a former Nasdaq listing and Metsera operates as part of Pfizer.
Metsera’s therapeutic focus and pipeline
Metsera’s pipeline centered on nutrient-stimulated hormone (NuSH) analogs and related peptide-based therapies for obesity and metabolic conditions. A key program was MET-097i, described in Metsera’s September 29, 2025 press release and related Form 8-K as a first-in-class fully biased, ultra-long acting GLP-1 receptor agonist (RA) with potential for monthly dosing. In Phase 2b trials VESPER-1 and VESPER-3 in participants with overweight or obesity without type 2 diabetes, MET-097i demonstrated dose-dependent weight loss and what the company characterized as potentially class-leading tolerability, with a placebo-like diarrhea profile and specified risk differences for nausea and vomiting at higher doses with titration.
Metsera reported that MET-097i achieved mean placebo-subtracted weight loss of up to 14.1% after 28 weeks at the highest evaluated weekly dose in VESPER-1, with low study discontinuation and high participant retention. VESPER-3 evaluated monthly dosing regimens and titration strategies, with an interim analysis focused on gastrointestinal tolerability. Based on these data, Metsera stated it was on track to initiate a global Phase 3 program for MET-097i in chronic weight management, and that MET-097i would serve as the foundational incretin backbone for multiple combination, oral, and prodrug programs.
According to Metsera’s disclosures, MET-097i underpinned four additional clinical and preclinical programs: MET-233/097, a monthly multi-NuSH combination with MET-233i, an ultra-long acting amylin agonist, in Phase 1/2a trials; MET-034/097, a combination with MET-034i, an ultra-long acting GIP receptor agonist, initiating Phase 1 studies; MET-097o, an oral form of MET-097 in Phase 1 trials; and MET-815, a prodrug of MET-097i designed for quarterly maintenance dosing in IND-enabling studies. These programs illustrate how Metsera sought to build a portfolio of injectable and oral incretin-based and related therapies aimed at chronic weight management and associated metabolic conditions.
HALO peptide stabilization and lipidation platform
Metsera described its HALO peptide stabilization and lipidation platform as a novel technology that enables peptides to bind simultaneously to albumin and to a drug target. Company materials state that this design is intended to facilitate a half-life approaching that of albumin and exceeding that of other NuSH peptides. The ultra-long half-life enabled by HALO was expected to support monthly dosing, improved tolerability, and scalability for therapies such as MET-097i and its combinations. This platform was a core element of Metsera’s approach to developing long-acting injectable and oral peptide therapeutics.
Corporate transactions and status of MTSR stock
Metsera’s strategic importance in the obesity and cardiometabolic treatment area is reflected in the competitive acquisition interest disclosed in its SEC filings and press releases. On September 21, 2025, Metsera entered into an Agreement and Plan of Merger with Pfizer, under which Pfizer agreed to acquire Metsera for cash plus non-transferable CVRs tied to specified clinical and regulatory milestones for MET-097i and the MET-233i/MET-097i combination product. Subsequent filings describe an amended merger agreement on November 7, 2025 that increased the upfront cash consideration and adjusted the CVR milestones and amounts.
During this period, Metsera also received unsolicited proposals from Novo Nordisk A/S, which its Board of Directors determined constituted a “Superior Company Proposal” under the Pfizer merger agreement, as described in Metsera’s October 30, 2025 and November 4, 2025 Forms 8-K. These filings outline proposed two-step transaction structures, interim funding, non-voting convertible preferred stock, and CVR terms. However, the November 13, 2025 Form 8-K confirms that the Pfizer transaction ultimately closed, and Metsera became a wholly owned subsidiary of Pfizer.
As a result of the completed merger and subsequent delisting steps, MTSR no longer trades on the Nasdaq Global Select Market. Former Metsera stockholders’ rights are limited to receipt of the merger consideration and any potential CVR milestone payments, as detailed in the CVR Agreement. For investors and researchers, the MTSR ticker now primarily serves as a historical reference to Metsera’s time as an independent, publicly traded clinical-stage biopharmaceutical company in the obesity and metabolic disease space.
How Metsera fit within the biotechnology and healthcare sector
Within the biotechnology industry and the broader healthcare sector, Metsera was positioned as a clinical-stage company focused on obesity and metabolic disease therapeutics. Its programs were disclosed as being in Phase 1 and Phase 2b development, with plans for Phase 3 initiation for MET-097i. The company’s strategy, as described in its press releases and SEC filings, emphasized long-acting peptide therapeutics, combination NuSH analogs, and both injectable and oral formulations targeting chronic weight management and related metabolic conditions.
Metsera’s acquisition by Pfizer integrated these assets into Pfizer’s Internal Medicine portfolio. Pfizer’s public statements about the transaction highlight that Metsera’s clinical-stage obesity candidates, including MET-097i and MET-233i, are viewed as complementary to Pfizer’s existing pipeline and as potential contributors to one of the most dynamic therapeutic areas in healthcare. For users researching MTSR, this context explains why Metsera attracted interest from large pharmaceutical companies and why its ticker is now associated with a completed change of control and delisting.
Key points for MTSR researchers
- MTSR historically represented Metsera, Inc., a clinical-stage biopharmaceutical company focused on obesity and metabolic diseases.
- Metsera’s lead program, MET-097i, is a fully biased, ultra-long acting GLP-1 receptor agonist with potential for monthly dosing, evaluated in Phase 2b trials VESPER-1 and VESPER-3.
- Metsera developed additional programs built on MET-097i, including combination, oral, and prodrug candidates, and utilized its HALO peptide stabilization and lipidation platform to extend peptide half-life.
- On November 13, 2025, Pfizer completed its acquisition of Metsera via merger, and Metsera became a wholly owned subsidiary of Pfizer.
- In connection with the merger, Metsera’s common stock was delisted from the Nasdaq Global Select Market, and the company moved to deregister its shares and suspend SEC reporting obligations.