Form 8-K

8-K — ASSEMBLY BIOSCIENCES, INC.

Accession: 0001193125-26-211922

Filed: 2026-05-07

Period: 2026-05-07

CIK: 0001426800

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Results of Operations and Financial Condition

Item: Financial Statements and Exhibits

Documents

8-K — asmb-20260507.htm (Primary)

EX-99.1 (asmb-ex99_1.htm)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K

8-K (Primary)

Filename: asmb-20260507.htm · Sequence: 1

8-K

0001426800false00014268002026-05-072026-05-07

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): May 7, 2026

Assembly Biosciences, Inc.

(Exact name of Registrant as Specified in Its Charter)

Delaware

001-35005

20-8729264

(State or Other Jurisdiction

of Incorporation)

(Commission File Number)

(IRS Employer

Identification No.)

Two Tower Place, 7th Floor,

South San Francisco, California

94080

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s Telephone Number, Including Area Code: (833) 509-4583

Not Applicable

(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:

☐

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, par value $0.001

ASMB

The 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 2.02 Results of Operations and Financial Condition.

On May 7, 2026, Assembly Biosciences, Inc. (the “Company”) issued a press release announcing its financial results for the quarter ended March 31, 2026. A copy of the press release is attached hereto as Exhibit 99.1.

The information furnished with this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such a filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit

Number

Description

99.1

Press Release dated May 7, 2026.

104

Cover Page Interactive Data File (embedded within 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.

Assembly Biosciences, Inc.

Date: May 7, 2026

By:

/s/ John O. Gunderson

John O. Gunderson

VP, General Counsel and Corporate Secretary

EX-99.1

Filename: asmb-ex99_1.htm · Sequence: 2

EX-99.1

Exhibit 99.1

Assembly Biosciences Reports First Quarter 2026 Financial Results and Recent Highlights

– Completed Phase 1b studies for ABI-5366 and ABI-1179, helicase-primase inhibitors for recurrent genital herpes –

– Completed chronic toxicology studies for ABI-6250, an oral small-molecule entry inhibitor candidate for chronic hepatitis delta virus; Phase 2 initiation anticipated Q4 2026 –

SOUTH SAN FRANCISCO, Calif. – May 7, 2026 – Assembly Biosciences, Inc. (Nasdaq: ASMB), a biotechnology company developing innovative therapeutics targeting serious viral diseases, today reported financial results for the first quarter ended March 31, 2026, and recent highlights.

“The first quarter reflected steady progress across our portfolio as we continue advancing our discovery and development programs,” said Jason Okazaki, chief executive officer and president of Assembly Bio. “As we look ahead, we anticipate receiving Gilead’s development plan and budget for the herpesvirus program and will evaluate our cost and profit share opt-in decision by mid-2026 while continuing to advance ABI-6250 toward Phase 2 in hepatitis delta virus by year-end.”

First Quarter 2026 and Recent Highlights

•

Completed follow-up period for all participants in the Phase 1b portion of the studies for ABI-5366 and ABI-1179, reinforcing continued confidence in the safety and efficacy findings previously disclosed for both candidates

•

Completed chronic toxicology studies for ABI-6250, establishing support for anticipated phase 2 doses

•

Presented an oral presentation and three posters, including one late-breaker, highlighting interim Phase 1b data for ABI-5366 and ABI-1179 at the 2026 Congress of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) in Munich, Germany

Anticipated Milestones and Events

•

By mid-2026, upon receipt of Gilead Sciences, Inc. (Gilead)’s development plan and budget for the helicase-primase inhibitor (HPI) program (ABI-5366 and ABI-1179) for recurrent genital herpes, Assembly Bio to determine whether to opt in to a 40% U.S. cost-profit share, in lieu of receiving U.S. milestones and royalties

•

Initiation of a Phase 2 clinical study for ABI-6250 in participants with chronic hepatitis delta virus (HDV) infection expected in the fourth quarter of 2026

Upcoming Conferences

•

European Association for the Study of the Liver (EASL) Congress: May 27-30, 2026 – Barcelona, Spain

ABI-5366, ABI-1179 and ABI-6250 are investigational product candidates that have not been approved anywhere globally, and their safety and efficacy have not been established. ABI-5366 and ABI-1179 are exclusively licensed to Gilead under the collaboration between Assembly Bio and Gilead, and Gilead has the sole right and responsibility for further clinical development and commercialization of the HPI program.

First Quarter 2026 Financial Results

•

Cash, cash equivalents and marketable securities were $226.6 million as of March 31, 2026, compared to $248.1 million as of December 31, 2025. The company’s cash position is projected to fund operations into 2028.

•

Revenue from collaborative research with Gilead was $8.2 million for the three months ended March 31, 2026, compared to $9.4 million for the same period in 2025. The decrease reflects the timing of activities performed and progress toward completion of services under the Gilead Collaboration Agreement.

•

Research and development expenses were $14.9 million for the three months ended March 31, 2026, consistent with the same period in 2025, with increases in employee compensation and research and discovery activities offset by decreases in external program expenses due to the completion of clinical trials.

•

General and administrative expenses were $4.7 million for the three months ended March 31, 2026, compared to $4.5 million for the same period in 2025, primarily driven by increased stock-based compensation related to performance-based awards.

•

Net loss attributable to common stockholders was $9.1 million, or $0.54 per basic and diluted share, for the three months ended March 31, 2026, compared to $8.8 million, or $1.17 per basic and diluted share, for the same period in 2025, reflecting a higher weighted-average share count in 2026.

About Assembly Biosciences

Assembly Biosciences is a biotechnology company dedicated to the development of innovative small-molecule therapeutics designed to change the path of serious viral diseases and improve the lives of patients worldwide. Led by an accomplished team of leaders in virologic drug development, Assembly Bio is committed to improving outcomes for patients struggling with the serious, chronic impacts of herpesvirus, hepatitis B virus (HBV) and hepatitis delta virus (HDV) infections. For more information, visit assemblybio.com.

Forward-Looking Statements

The information in this press release contains forward-looking statements that are subject to certain risks and uncertainties that could cause actual results to materially differ. These risks and uncertainties include: Assembly Bio’s ability to realize the potential benefits of its collaboration with Gilead, including all financial aspects of the collaboration and equity investments; Assembly Bio’s ability to initiate and complete clinical studies involving its therapeutic product candidates, including studies contemplated by Assembly Bio’s collaboration with Gilead, in the currently anticipated timeframes or at all; safety and efficacy data from clinical or nonclinical studies may not warrant further development of Assembly Bio’s product candidates; clinical and nonclinical data may not differentiate Assembly Bio’s product candidates from other companies’ candidates; Assembly Bio’s ability to maintain financial resources and secure additional funding necessary to continue its research activities, clinical studies, and other business operations; potential effects of changes in government regulation; results of nonclinical studies may not be representative of disease behavior in a clinical setting and may not be predictive of the outcomes of clinical studies; and other risks identified from time to time in Assembly Bio’s reports filed with the U.S. Securities and Exchange Commission (the SEC). You are urged to consider statements that include the words may, will, would, could, should, might, believes, hopes, estimates, projects, potential, expects, plans, anticipates, intends, continues, forecast, designed, goal or the negative of those words or other comparable words to be uncertain and forward-looking. Assembly Bio intends such forward-looking statements to be covered by the safe harbor provisions contained in Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. More information about Assembly Bio’s risks and uncertainties are more fully detailed under the heading “Risk Factors” in Assembly Bio’s filings with the SEC, including its most recent Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K. Except as required by law, Assembly Bio assumes no obligation to update publicly any forward-looking statements, whether as a result of new information, future events or otherwise.

Contacts:

Investors:

Patrick Till

Meru Advisors

(484) 788-8560

investor_relations@assemblybio.com

Media:

Sam Brown LLC

Jamie Strachota

(703) 819-7647

ASMBMedia@sambrown.com

ASSEMBLY BIOSCIENCES, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS

(In thousands except for share amounts and par value)

March 31,

December 31,

2026

2025

(Unaudited)

ASSETS

Current assets

Cash and cash equivalents

31,120

58,450

Marketable securities

195,481

189,656

Accounts receivable from collaboration with a related party

451

974

Prepaid expenses and other current assets

5,561

5,469

Total current assets

232,613

254,549

Property and equipment, net

214

221

Operating lease right-of-use assets

2,369

2,508

Other assets

312

Total assets

235,508

257,590

LIABILITIES AND STOCKHOLDERS' EQUITY

Current liabilities

Accounts payable

1,129

1,171

Accrued research and development expenses

1,538

2,387

Other accrued expenses

2,664

7,749

Deferred revenue from a related party

29,076

36,904

Operating lease liabilities - short-term

590

569

Total current liabilities

34,997

48,780

Operating lease liabilities - long-term

1,901

2,059

Total liabilities

36,898

50,839

Commitments and contingencies

Stockholders' equity

Preferred stock, $0.001 par value; 5,000,000 shares authorized; no shares issued or outstanding

—

Common stock, $0.001 par value; 150,000,000 shares authorized as of March 31, 2026 and December 31, 2025; 15,892,353 and 15,855,329 shares issued and outstanding as of March 31, 2026 and December 31, 2025, respectively

Additional paid-in capital

1,040,088

1,038,823

Accumulated other comprehensive loss

(368

)

(41

)

Accumulated deficit

(841,126

)

(832,047

)

Total stockholders' equity

198,610

206,751

Total liabilities and stockholders' equity

235,508

257,590

ASSEMBLY BIOSCIENCES, INC.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(In thousands except for share and per share amounts)

(Unaudited)

Three Months Ended March 31,

2026

2025

Collaboration revenue from a related party

8,213

9,419

Operating expenses

Research and development

14,900

14,851

General and administrative

4,683

4,509

Total operating expenses

19,583

19,360

Loss from operations

(11,370

)

(9,941

)

Other income

Interest and other income, net

2,291

1,123

Total other income

2,291

1,123

Net loss

(9,079

)

(8,818

)

Other comprehensive loss

Unrealized loss on marketable securities

327

Comprehensive loss

(9,406

)

(8,860

)

Net loss per share, basic and diluted

(0.54

)

(1.17

)

Weighted average common shares outstanding, basic and diluted

16,900,232

7,506,321

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