Form 8-K
8-K — Gossamer Bio, Inc.
Accession: 0001728117-26-000057
Filed: 2026-07-01
Period: 2026-07-01
CIK: 0001728117
SIC: 2834 (PHARMACEUTICAL PREPARATIONS)
Item: Regulation FD Disclosure
Item: Financial Statements and Exhibits
Documents
8-K — goss-20260701.htm (Primary)
EX-99.1 (goss-20260701xexx991xprcon.htm)
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8-K
8-K (Primary)
Filename: goss-20260701.htm · Sequence: 1
goss-20260701
0001728117FALSE00017281172026-07-012026-07-01
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 8-K
CURRENT REPORT
Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
Date of Report (Date of earliest event reported): July 1, 2026
GOSSAMER BIO, INC.
(Exact name of Registrant as Specified in Its Charter)
Delaware 001-38796 47-5461709
(State or Other Jurisdiction
of Incorporation) (Commission File Number) (IRS Employer
Identification No.)
3115 Merryfield Row, Suite 120
San Diego, California, 92121
(Address of Principal Executive Offices) (Zip Code)
(858) 684-1300
(Registrant’s Telephone Number, Including Area Code)
N/A
(Former Name or Former Address, if Changed Since Last Report)
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instructions A.2. below):
☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
☐
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
Securities registered pursuant to Section 12(b) of the Act:
Title of each class Trading
Symbol(s) Name of each exchange on which registered
Common Stock, $0.0001 par value per share GOSS Nasdaq Global Select Market
Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).
Emerging growth company ☐
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐
Item 7.01 Regulation FD Disclosure.
On July 1, 2026, Gossamer Bio, Inc. (“Gossamer” or the “Company”) issued a press release announcing that the initial conversion rate for its 7.50% Convertible Senior Secured First Lien Notes due 2030 (the “2030 Convertible Notes”) will be 5,347.5936 shares of the Company’s common stock per $1,000 principal amount of the 2030 Convertible Notes, which represents a conversion price of approximately $0.19 per share of common stock, and the initial exercise price of its warrants to purchase shares of common stock (the “Purchase Warrants”) will be $0.34 per whole share of its common stock. A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K.
Item 9.01 Financial Statements and Exhibits.
(d) Exhibits.
Exhibit
Number Description
99.1
Press release of Gossamer Bio, Inc. dated July 1, 2026.
104 Cover page interactive data file (embedded with the inline XBRL document)
SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.
GOSSAMER BIO, INC.
Date: July 1, 2026 By: /s/ Christian Waage
Christian Waage
Executive Vice President and General Counsel
EX-99.1
EX-99.1
Filename: goss-20260701xexx991xprcon.htm · Sequence: 2
Document
Exhibit 99.1
Gossamer Bio, Inc. Announces Determination of Conversion Rate for 7.50% Convertible Senior Secured First Lien Notes due 2030 and Exercise Price for Purchase Warrants
San Diego, California. (July 1, 2026) – Gossamer Bio, Inc. (NASDAQ: GOSS) (the “Company” or “Gossamer”), a biopharmaceutical company focused on the development and commercialization of seralutinib for the treatment of pulmonary arterial hypertension (PAH) and pulmonary hypertension associated with interstitial lung disease (PH-ILD), today announced that the initial conversion rate for its 7.50% Convertible Senior Secured First Lien Notes due 2030 (the “2030 Convertible Notes”) will be 5,347.5936 shares of the Company’s common stock per $1,000 principal amount of the 2030 Convertible Notes, which represents a conversion price of approximately $0.19 per share of common stock, and the initial exercise price of its warrants to purchase shares of common stock (the “Purchase Warrants”) will be $0.34 per whole share of its common stock.
The “Reference Price,” which was calculated over a seven trading-day period beginning on June 22, 2026 in accordance with the terms of the 2030 Convertible Notes and Purchase Warrants, was determined to be $0.17. The initial conversion rate applicable to the 2030 Convertible Notes was calculated as the lesser of (i) 5,347.5936 and (ii) 1,000 divided by 110% of the Reference Price. The initial exercise price applicable to the Purchase Warrants was calculated as the greater of (i) $0.34 and (ii) 125% of the Reference Price.
This press release is for informational purposes only and does not constitute an offer to sell, or the solicitation of an offer to buy, any securities referred to in this press release.
About Gossamer Bio
Gossamer Bio is a biopharmaceutical company focused on the development of treatments for pulmonary hypertension. Its goal is to be an industry leader in, and to enhance the lives of patients living with, pulmonary hypertension.
For Investors and Media:
Bryan Giraudo, Chief Financial Officer & Chief Operating Officer
Gossamer Bio Investor Relations
ir@gossamerbio.com
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