PRLD

EX-99.1

2 prld-ex99_1.htm

EX-99.1

EX-99.1

Exhibit 99.1

Prelude Therapeutics Reports Second Quarter 2026 Financial Results and Provides Corporate Update

The Company expects to initiate its Phase 1 study of PRT13722, a first-in-class highly-selective oral KAT6A degrader in HR+ breast cancer in the fourth quarter

Presented preclinical data demonstrating differentiated profile of PRT13722, at the American Association for Cancer Research (AACR) Annual Meeting 2026

Enrollment continues in Phase 1 Study of PRT12396, mutant-selective JAK2V617F inhibitor in patients with polycythemia vera (PV) and myelofibrosis (MF)

Current cash runway expected into the second quarter of 2028 with $155 million in cash, cash equivalents, restricted cash and marketable securities as of June 30, 2026

WILMINGTON, Del., Aug. 11, 2026 (GLOBE NEWSWIRE) – Prelude Therapeutics Incorporated (Nasdaq: PRLD), a clinical-stage precision oncology company, today reported its financial results for the second quarter ended June 30, 2026 and provided an update on its R&D pipeline and other corporate developments.

"The first six months of 2026 were highlighted by steady and strong execution across our organization,” stated Kris Vaddi, Ph.D., Chief Executive Officer of Prelude. “We’ve made considerable progress advancing our three core programs. Notably, we are well positioned to initiate, in the fourth quarter, the first clinical trial of our highly differentiated, selective KAT6A degrader, PRT13722 in HR+ breast cancer. Enrollment in our phase 1 study of PRT12396, our mutant-selective JAK2V617F inhibitor, continues, and we are also making excellent progress toward advancing the lead development candidates from our mCALR degrader antibody conjugate program.”

Program Updates and Upcoming Milestones

Highly selective KAT6A oral degrader program

KAT6 is an emerging and recently validated target in the treatment of HR+ breast cancer. Prelude discovered and is developing first-in-class, highly potent, highly selective and orally bioavailable KAT6A selective degraders. Pending clearance of the IND application, the Company expects the phase 1 study initiation of PRT13722 in HR+ breast cancer in the fourth quarter of 2026. Prelude believes that selectively degrading KAT6A has the potential for

Exhibit 99.1

improved efficacy, tolerability and combinability with other agents relative to non-selective inhibitors of KAT6A/B.

The Company presented preclinical data supporting this hypothesis at the AACR Annual Meeting 2026. The presentation can be found at Publications - Prelude Therapeutics.

Mutant selective JAK2V617F JH2 inhibitor program

JAK2V617F is the primary driver mutation responsible for disease progression in the majority of patients living with myeloproliferative neoplasms (MPNs). The mutation impacts approximately 95% of patients with polycythemia vera (PV), 60% of patients with essential thrombocythemia (ET) and 55% of patients with myelofibrosis (MF). Identifying JAK2 JH2 inhibitors that selectively target V617F+ cells has long been the goal for advancing the treatment of MPNs. Prelude has designed and identified novel allosteric inhibitors that bind into the JAK2 JH2 “deep pocket” where the V617F mutation resides. These candidates demonstrate mutant specific inhibition in multiple preclinical models of MPNs. Prelude believes this approach may have the potential to reduce mutant allele burden, slow or even reverse disease progression, and transform treatment outcomes for MPN patients.

PRT12396, Prelude’s lead, mutant-selective JAK2V617F inhibitor, received IND clearance from the U.S. Food and Drug Administration, as previously announced in February 2026 and is currently enrolling patients into a Phase 1 study of PRT12396 in patients with PV and MF. The Company also continues to make progress advancing next generation development candidates with potential best-in-class selectivity profiles.

The JAK2V617F inhibitor program is subject to an exclusive option agreement with Incyte announced in November 2025.

Mutated calreticulin (mCALR) DAC discovery program

Mutant CALR is a neoantigen presented on the cell surface of malignant myeloid cells but not normal cells and is found in approximately 25-35% of patients with MF and essential thrombocythemia (ET). Recently, a mCALR-targeted monoclonal antibody demonstrated robust clinical activity in high-risk ET patients. Prelude is advancing mCALR-targeted degrader antibody conjugates (DACs) using the Company’s proprietary degrader payloads as a differentiated approach for patients with CALR mutations. This discovery program is wholly owned and controlled by Prelude.

The Company presented the preclinical data from the program at the European Hematology Association 2025 Congress in June and the American Society of Hematology (ASH) 67th Annual Meeting in December 2025. The presentations can be found at Publications – Prelude Therapeutics.

Degrader payloads for next generation DACs

Prelude is l

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8-K

0001678660false00016786602026-03-102026-03-10

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): March 10, 2026

Prelude Therapeutics Incorporated (Exact Name of Registrant as Specified in its Charter)

Delaware

001-39527

81-1384762

(State or other jurisdiction of incorporation or organization)

(Commission File Number)

(I.R.S. Employer Identification No.)

175 Innovation Boulevard Wilmington, Delaware

19805

(Address of principal executive offices)

(Zip Code)

Registrant’s telephone number, including area code: (302) 467-1280 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, $0.0001 par value per share

PRLD

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 March 10, 2026, Prelude Therapeutics Incorporated (the "Company") issued a press release announcing its financial results for the year ended December 31, 2025. A copy of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K.

Item 7.01 Regulation FD Disclosure. The Company has prepared investor presentation materials with information about the Company, which it intends to use as part of investor presentations. A copy of the investor presentation materials to be used by management for presentations is attached as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated herein by reference. The information in this Current Report on Form 8-K and in Exhibits 99.1 and 99.2 attached hereto is being furnished, but shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (“Exchange Act”), and is not incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date hereof, regardless of any general incorporation language in such filing.

Item 9.01 Financial Statements and Exhibits. (d) Exhibits

Exhibit Number

Description

99.1

Press Release dated March 10, 2026

99.2

Presentation

104

Cover Page Interactive Data File (embedded within the Inline XBRL Document)

SIGNATURE

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.

PRELUDE THERAPEUTICS INCORPORATED

Date: March 10, 2026

By:

/s/ Bryant Lim

Bryant Lim

Chief Financial Officer and Chief Legal Officer