Welcome to our dedicated page for MBX Biosciences SEC filings (Ticker: MBX), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
The MBX Biosciences, Inc. (Nasdaq: MBX) SEC filings page on Stock Titan provides access to the company’s regulatory disclosures as filed with the U.S. Securities and Exchange Commission. As a clinical-stage biopharmaceutical company and emerging growth company, MBX uses filings such as Forms S-1, 10-K, 10-Q, and 8-K to describe its Precision Endocrine Peptide™ (PEP™) platform, clinical programs, risk factors, and capital-raising activities.
In its S-1 registration statement, MBX outlines its focus on novel precision peptide therapies for endocrine and metabolic disorders and details key product candidates, including canvuparatide (MBX 2109) for chronic hypoparathyroidism, imapextide (MBX 1416) for post-bariatric hypoglycemia, and MBX 4291 for obesity. Subsequent 8-K filings report material events such as topline results from the Phase 2 Avail™ trial of canvuparatide, initiation of the Phase 1 trial of MBX 4291, public equity offerings, and changes in board and committee roles.
Through this page, users can review MBX’s periodic financial reports, which discuss research and development spending, cash and marketable securities, and expectations about funding operations, as well as prospectus materials that describe intended uses of offering proceeds. Form 8-K filings also summarize key clinical data, trial designs, and future development plans for the company’s programs.
Stock Titan enhances these filings with AI-powered summaries that highlight the main points of lengthy documents, helping readers quickly understand topics such as clinical results, financing terms, and governance updates. Real-time updates from EDGAR, along with structured access to material event reports and registration statements, make this page a central resource for analyzing MBX’s regulatory and financial disclosures.
MBX Biosciences filed an S-3 shelf registration to offer, issue and sell up to $400,000,000 of securities from time to time. The filing also includes a sales agreement prospectus supplement for an at-the-market program to sell up to $150,000,000 of common stock through Jefferies LLC, which is included within the $400,000,000 shelf capacity.
Sales may occur on a continuous or delayed basis, with specific terms set in future supplements. The company states that net proceeds will be used for development of clinical-stage programs, discovery R&D, additional clinical development, and general corporate purposes, including working capital and capital expenditures.
MBX’s common stock trades on the Nasdaq Global Select Market under “MBX.” The last reported sale price was $20.62 per share on November 4, 2025. Shares outstanding were 44,715,498 as of September 30, 2025.
MBX Biosciences (MBX) filed its Q3 2025 10‑Q, highlighting a stronger balance sheet after a September underwritten offering. The company reported a net loss of $21.6 million for the quarter as operating expenses rose with pipeline advancement. Research and development was $19.3 million and general and administrative was $4.7 million, reflecting continued clinical activity.
Liquidity improved materially: cash, cash equivalents and marketable securities were $391.7 million as of September 30, 2025, supported by the September 2025 offering of 11,108,055 shares at $18.00 for $187.4 million in net proceeds. Total assets were $400.1 million and stockholders’ equity was $387.5 million.
Pipeline updates: canvuparatide met the primary endpoint in Phase 2; the company plans End of Phase 2 interactions in Q1 2026 and a Phase 3 start in Q3 2026. MBX 4291 is in Phase 1 for obesity, and imapextide showed positive Phase 1 results with a Phase 2a in progress. Shares outstanding were 44,715,498 as of September 30, 2025; 44,902,302 as of November 3, 2025.
MBX Biosciences filed an 8-K noting it furnished a press release announcing financial results for the quarter ended September 30, 2025. The release is provided as Exhibit 99.1 and is furnished, not filed, under Item 2.02.
Under Item 5.02, the company reported governance updates. On October 31, 2025, James M. Cornelius resigned from the Board and as Audit Committee chair; the company stated there was no disagreement with MBX regarding operations, policies or practices. Effective November 6, 2025, director Steven Hoerter was appointed executive chairperson. He will receive chair compensation and an option to purchase 100,000 shares vesting monthly over one year. The Audit Committee now comprises Tiba Aynechi (chair), Steven Hoerter, and Ed Mathers.
MBX Biosciences (MBX) reported an insider transaction by its President & CEO and Director on 10/24/2025. The executive exercised a stock option (Code M) to acquire 182,859 shares of common stock at an exercise price of $3.25 per share. Following the transaction, beneficial ownership stood at 664,256 shares held directly and 468,277 shares held indirectly through a revocable trust. The filing lists 129,708 derivative securities (options) remaining post-transaction. The option began vesting monthly from 11/07/2022 and is scheduled to fully vest by 11/07/2026, with early-exercise permitted subject to an issuer repurchase right.
MBX Biosciences (MBX) reported an insider share purchase by its President & CEO and Director on 10/20/2025. The reporting person bought 20,000 shares of common stock at a weighted average price of $13.6395, with trades executed between $13.60 and $13.6399.
Following the transaction, the filing lists 481,397 shares as directly owned and 468,277 shares as indirectly owned by a trust. The trust is identified as the P. Kent Hawryluk Revocable Trust, with the reporting person serving as trustee.
MBX Biosciences (MBX) reported an insider purchase by a director. On 10/17/2025, a revocable trust of the reporting person acquired 20,000 shares of common stock at $13.2492 per share (Transaction Code P). Following the transaction, 20,000 shares were beneficially owned indirectly by the trust. The filer notes a disclaimer of beneficial ownership beyond any pecuniary interest, as stated in the footnote.
Wellington Management reports ownership of
OrbiMed affiliates report a change in beneficial ownership of MBX Biosciences common stock following an increase in the company's outstanding shares. The filing discloses that OrbiMed Advisors, OrbiMed Capital GP VII and OrbiMed Genesis collectively hold 4,002,887 shares, representing approximately 9.0% of 44,700,281 outstanding shares as stated in the issuer's prospectus. The reduction in reported percentage ownership is due to an increase in shares outstanding rather than a sale by the reporting persons. The filing also summarizes the relationships among the funds, their voting and dispositive authority and limited registration and piggyback rights under an Investors' Rights Agreement.
Amendment No. 1 to the Schedule 13D reports that Norwest Venture Partners XVI, LP and affiliated reporting persons experienced dilution in their ownership of MBX Biosciences, Inc. common stock as a result of an underwritten public offering that closed on September 26, 2025. The filing states each of the primary reporting persons beneficially owns 2,136,335 shares, representing 4.8% of the class based on 33,607,443 shares outstanding as of August 31, 2025 plus 11,108,055 shares issued in the offering; Ms. Aynechi’s aggregate beneficial ownership is reported as 2,140,989 shares (including 4,654 option shares). The reporting group ceased to be beneficial owners of more than 5% on September 26, 2025. The amendment discloses no transactions in the past 60 days and incorporates a prior joint filing agreement as an exhibit.
Frazier-affiliated investment vehicles disclosed their holdings in MBX Biosciences, Inc. Frazier Life Sciences X, L.P. directly holds 5,219,440 shares of common stock, representing 11.7% of the class based on the filing's share-count assumptions. Frazier Life Sciences Public Fund, L.P. holds 1,103,920 shares (2.5%), and Frazier Life Sciences Public Overage Fund, L.P. holds 325,653 shares (0.7%). The filing details pre-IPO purchases of preferred stock that converted at a 12.0221-to-1 ratio at IPO, IPO purchases at $16.00 per share, and a post-IPO purchase on September 26, 2025 by FLS X of 666,666 shares at $18.00 per share. The filing clarifies voting and dispositive power allocations among related entities and identifies exhibits, including an investors' rights agreement and a transactions exhibit.