Form 8-K

8-K — Armata Pharmaceuticals, Inc.

Accession: 0001104659-26-056658

Filed: 2026-05-07

Period: 2026-05-07

CIK: 0000921114

SIC: 2836 (BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES))

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — tm2613773d1_8k.htm (Primary)

EX-99.1 — EXHIBIT 99.1 (tm2613773d1_ex99-1.htm)

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UNITED STATES

SECURITIES AND

EXCHANGE COMMISSION

Washington, DC

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):

May 7, 2026

ARMATA PHARMACEUTICALS, INC.

(Exact name of Registrant as specified in

its charter)

Washington

001-37544

91-1549568

(State or other jurisdiction

of incorporation or

organization)

(Commission File Number)

(IRS Employer Identification No.)

5005 McConnell Avenue

Los Angeles, California

90066

(Address of principal executive offices)

(Zip Code)

(310) 665-2928

(Registrant’s Telephone number)

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 Instruction 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))

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. ¨

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

ARMP

NYSE American

Item 7.01

Regulation FD Disclosure.

On May 7, 2026, Armata Pharmaceuticals, Inc. (the “Company”)

issued a press release announcing that the U.S. Food and Drug Administration has granted Fast Track Designation to AP-SA02, the Company’s

intravenously administered Staphylococcus aureus (“S. aureus”) multi-phage product candidate, for adjunct treatment

of complicated bacteremia caused by methicillin-sensitive S. aureus or methicillin-resistant S. aureus. The full text of

the press release issued in connection with this announcement is furnished as Exhibit 99.1 to this Current Report on Form 8-K.

The information in this Item 7.01 and the attached Exhibit 99.1 is

being furnished and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as

amended, or otherwise subject to the liabilities of that Section. The information in this Item 7.01 and the attached Exhibit 99.1 shall

not be incorporated by reference into any registration statement or other document pursuant to the Securities Act of 1933, as amended.

Item 9.01

Financial Statements and Exhibits.

(d) Exhibits.

Exhibit

No.

Description

99.1

Press Release, dated May 7, 2026.

104

Cover Page Interactive Data File (embedded within Inline XBRL document).

- 2 -

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 hereunto duly authorized.

Date: May 7, 2026

Armata Pharmaceuticals, Inc.

By:

/s/ David House

Name:

David House

Title:

Senior Vice President, Finance and Principal Financial Officer

- 3 -

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2613773d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

Armata Pharmaceuticals Secures FDA Fast Track

Designation for AP-SA02

Enables more frequent FDA engagement, rolling

Biologic License Application review, and the potential for Accelerated Approval and Priority Review upon successful clinical development

Advances AP-SA02 on a faster path to potential

approval and patient access

LOS ANGELES, Calif., May 7, 2026 -- Armata Pharmaceuticals,

Inc. (NYSE American: ARMP) (“Armata” or the “Company”), a late clinical-stage biotechnology company focused on

the development of high-purity, pathogen-specific bacteriophage therapeutics for the treatment of antibiotic-resistant and difficult-to-treat

bacterial infections, today announced that the U.S. Food and Drug Administration (the “FDA”) has granted Fast Track Designation

to AP-SA02, the Company's intravenously administered Staphylococcus aureus (“S. aureus”) multi-phage product

candidate, for adjunct treatment of complicated bacteremia caused by methicillin-sensitive S. aureus (“MSSA”) or methicillin

resistant S. aureus (“MRSA”).

“We are pleased to receive Fast Track designation

from the FDA for AP-SA02, which marks another important milestone for this program and underscores both the seriousness of complicated

S. aureus bacteremia (“SAB”) and the urgent need for effective new treatment options,” said Dr. Deborah Birx,

Chief Executive Officer of Armata Pharmaceuticals. “This designation recognizes the potential of AP-SA02 to improve upon current

standard of care treatment options for complicated SAB, a common, extremely severe, and often deadly infection, and highlights the strength

of Armata’s phage platform to deliver differentiated therapies for bacterial infections. As we advance toward the initiation of

our Phase 3 superiority study, anticipated to begin in the second half of 2026, we remain focused on executing efficiently and look forward

to interacting more frequently with the FDA throughout the clinical development and review process, with the goal of bringing this novel

antibacterial therapy to patients as quickly as possible.”

Fast Track designation is intended to facilitate

the development and expedite the review of investigational therapies that treat serious conditions and fill an unmet medical need. The

designation provides for more frequent interactions with the FDA regarding all aspects of a designated drug’s clinical development

program, supporting a more efficient path to registration. Fast Track designation also allows for rolling review of a Biologics License

Application (“BLA”), meaning completed sections may be submitted and reviewed on an ongoing basis rather than waiting for

the full application. Additionally, Fast Track-designated programs may also be eligible for Accelerated Approval and Priority Review

if supported by clinical data at the time of BLA submission, further supporting a faster path to potential approval and patient access.

For more information on the Fast Track designation, visit the FDA’s official website.

About AP-SA02

Armata is developing AP-SA02, a fixed multi-phage

cocktail, for the adjunct treatment of complicated Staphylococcus aureus bacteremia caused by methicillin-sensitive S. aureus

(MSSA) or methicillin resistant S. aureus (MRSA). The diSArm study (NCT05184764) was a Phase 1b/2a, multicenter, randomized, double-blind,

placebo-controlled, multiple ascending dose escalation study of the safety, tolerability, and efficacy of intravenous AP-SA02 in addition

to best available antibiotic therapy (“BAT”) compared to BAT alone (placebo) for the treatment of adults with complicated

S. aureus bacteremia. Positive results from the Phase 2a diSArm study were highlighted in a late-breaking oral presentation

at IDWeek 2025™ in October 2025. The Phase 1b/2a clinical development of AP-SA02 was partially supported by a $26.2 million

Department of Defense (DoD) award, received through the Medical Technology Enterprise Consortium (MTEC) and managed by the Naval Medical

Research Command (NMRC) – Naval Advanced Medical Development (NAMD) with funding from the Defense Health Agency and Joint Warfighter

Medical Research Program. The Company plans to advance AP-SA02 into a Phase 3 superiority study in complicated S. aureus bacteremia,

anticipated to initiate in the second half of 2026.

About Armata Pharmaceuticals, Inc.

Armata is a late clinical-stage biotechnology

company focused on the development of high-purity pathogen-specific bacteriophage therapeutics for the treatment of antibiotic-resistant

and difficult-to-treat bacterial infections using its proprietary bacteriophage-based technology. Armata is developing and advancing a

broad pipeline of natural and synthetic phage candidates, including clinical candidates for Pseudomonas aeruginosa, S. aureus,

and other important pathogens. Armata is committed to advancing phage therapy with drug development expertise that spans bench to clinic

including in-house phage-specific current Good Manufacturing Practices (“cGMP”) manufacturing to support full commercialization.

Forward Looking Statements

This communication contains “forward-looking”

statements as defined by the Private Securities Litigation Reform Act of 1995. These statements relate to future events, results or to

Armata’s future financial performance and involve known and unknown risks, uncertainties and other factors which may cause Armata’s

actual results, performance or events to be materially different from any future results, performance or events expressed or implied by

the forward-looking statements. In some cases, you can identify these statements by terms such as “anticipate,” “believe,”

“could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,”

“predict,” “project,” “should,” “will,” “would” or the negative of those terms,

and similar expressions. These forward-looking statements reflect management’s beliefs and views with respect to future events and

are based on estimates and assumptions as of the date of this communication and are subject to risks and uncertainties including risks

related to Armata’s development of bacteriophage-based therapies; Armata's planned clinical trials; ability to staff and maintain

its production facilities under fully compliant cGMP; ability to meet anticipated milestones in the development and testing of the relevant

product; ability to be a leader in the development of phage-based therapeutics; ability to achieve its vision, including improvements

through engineering and success of clinical trials; ability to successfully complete preclinical and clinical development of, and obtain

regulatory approval of its product candidates and commercialize any approved products on its expected timeframes or at all; and Armata’s

estimates regarding anticipated operating losses, capital requirements and needs for additional funds. Additional risks and uncertainties

relating to Armata and its business can be found under the caption “Risk Factors” and elsewhere in Armata’s filings

and reports with the U.S. Securities and Exchange Commission (the “SEC”), including in Armata’s Annual Report on Form

10-K, filed with the SEC on March 25, 2026, and in its subsequent filings with the SEC.

Armata expressly disclaims any obligation or undertaking

to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in Armata’s

expectations with regard thereto or any change in events, conditions or circumstances on which any such statements are based.

Media Contacts:

At Armata:

Pierre Kyme

ir@armatapharma.com

310-665-2928

Investor Relations:

Joyce Allaire

LifeSci Advisors, LLC

jallaire@lifesciadvisors.com

212-915-2569

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