Form 8-K

8-K — Armata Pharmaceuticals, Inc.

Accession: 0001104659-26-109809

Filed: 2026-09-23

Period: 2026-09-23

CIK: 0000921114

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

Item: Other Events

Item: Financial Statements and Exhibits

Documents

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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):

September 23, 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 8.01

Other Events.

On September 23, 2026, Armata Pharmaceuticals, Inc.

(the “Company”) issued a press release announcing that it has received $3.7 million in additional non-dilutive funding from

the U.S. Department of War (“DoW”) to support activities associated with the Phase 3 development program for AP-SA02, the

Company’s intravenously administered Staphylococcus aureus (“S. aureus”) multi-phage product candidate

for the 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 attached as Exhibit 99.1 to this Current Report

on Form 8-K and incorporated herein by reference.

Item 9.01

Financial Statements and Exhibits.

(d) Exhibits.

Exhibit

No.

Description

99.1

Press Release, dated September 23, 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: September 23, 2026

Armata Pharmaceuticals, Inc.

By:

/s/ David House

Name:

David House

Title:

Chief Financial Officer

- 3 -

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2625977d1_ex99-1.htm · Sequence: 2

Exhibit 99.1

Armata Pharmaceuticals

Receives $3.7 Million in Additional Non-Dilutive Funding from U.S. Department of War to Support Advancement of AP-SA02 Phase 3 Development

Initial Phase

3-focused funding to support advancement of AP-SA02 in complicated Staphylococcus aureus bacteremia

New commitment

is incremental to previously announced DoW funding and expands total non-dilutive support for the AP-SA02 program to $32.4 million

LOS ANGELES,

Calif., September 23, 2026 - Armata Pharmaceuticals, Inc. (NYSE American: ARMP) (“Armata” or the “Company”),

a late clinical-stage biotechnology company focused on the development of high-purity and potency, pathogen-specific bacteriophage therapeutics

for the treatment of antibiotic-resistant and difficult-to-treat bacterial infections, today announced that it has received an additional

$3.7 million in non-dilutive funds from the U.S. Department of War (“DoW”) to support activities associated with the Phase

3 development program for AP-SA02.

Importantly, the $3.7 million represents the first funding received

specifically for Phase 3 execution pursuant to a previously announced DoW 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. This funding follows the

$28.7 million previously provided, bringing cumulative non-dilutive DoW funding under the award to approximately $32.4 million and underscoring

the U.S. government’s continued interest in advancing the AP-SA02 program.

Armata’s lead clinical candidate, AP-SA02, is being developed

as an adjunctive treatment for complicated Staphylococcus aureus bacteremia (“SAB”) caused by methicillin-sensitive

S. aureus (MSSA) or methicillin-resistant S. aureus (“MRSA”). The additional funding will be used to support

the Phase 3 clinical program for AP-SA02.

“The

DoW has supported the AP-SA02 program through multiple stages of its development, and these new funds extend that support into Phase 3,”

said Dr. Deborah Birx, Chief Executive Officer of Armata.

“We believe the continued commitment of non-dilutive federal

funding reflects the importance of developing new approaches to serious and difficult-to-treat bacterial infections, including antibiotic-resistant

S. aureus. Complicated SAB remains associated with substantial morbidity and mortality in both military and civilian populations,

underscoring the need for therapies that can complement existing antibiotics and improve outcomes for patients.”

Dr. Birx continued, “We view

this funding as the first commitment of DoW support for the Phase 3 program, and we intend to continue working closely with the DoW regarding

potential additional support as the Phase 3 study advances. Our long-standing collaboration has helped us move the program from early

clinical development toward a pivotal study, while providing meaningful non-dilutive capital to support its advancement.”

About AP-SA02

Armata is

developing AP-SA02, a fixed multi-phage cocktail, for the adjunct treatment of complicated SAB bacteremia caused by MSSA or MRSA. AP-SA02

has received Qualified Infectious Disease Product (QIDP) designation, Fast Track designation, and Breakthrough

Therapy designation from the FDA. 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 SAB. Positive

results from the Phase 2a diSArm study were highlighted in a late-breaking oral presentation at IDWeek 2025™ in October

2025. The Company plans to advance AP-SA02 into a Phase 3 superiority study in complicated SAB, 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 and potency, 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, Staphylococcus

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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