Harpoon Therapeutics to Host Webcast Reviewing HPN328 Interim Data Presented at ESMO Congress 2023 on October 23, 2023

SOUTH SAN FRANCISCO, Calif., Oct. 16, 2023 (GLOBE NEWSWIRE) — Harpoon Therapeutics, Inc. (Nasdaq: HARP), a clinical-stage immunotherapy company developing novel T cell engagers, today announced that it will host a live webcast at 8:00 a.m. ET / 2:00 p.m. CEST on Monday, October 23, 2023 to review interim monotherapy data from its Phase 1/2 clinical trial evaluating HPN328 in small cell lung cancer (SCLC) and other neuroendocrine neoplasms (NEN) presented at the European Society of Medical Oncology Congress (ESMO) 2023.

During the call, management will provide an in-depth review of the HPN328 interim data presented that day at ESMO Congress 2023. Harpoon will present data from over 70 patients across multiple DLL3 expressing tumor types in HPN328 monotherapy cohorts, with an emphasis on the ongoing 1 mg priming cohorts with target doses up to 24 mg. Full enrollment of these 1 mg priming dose cohorts will be the basis for selecting the recommended Phase 2 dose(s) by the end of this year. The ESMO poster will share tolerability data from all enrolled patients and preliminary response data in patients at doses above the efficacious threshold of 1.215 mg. For more on the ESMO abstract, please see the October 9, 2023 press release.

Registration Information
The live webcast will take place on Monday, October 23, 2023, from 8:00 a.m. to 9:00 a.m. ET / 2:00 p.m. to 3:00 p.m. CEST. To register for the event, please click here. A replay of the webcast will be available shortly after the live event and can be accessed at the same weblink.

Details of the ESMO poster presentation are as follows:

Abstract Title: Interim Results from a Phase 1/2 Study of HPN328, a Tri-Specific, Half-Life (T1/2) Extended DLL3-targeting T-Cell Engager in Patients (pts) with Small Cell Lung Cancer (SCLC) and other Neuroendocrine Neoplasms (NEN)
Presentation Number: 698P
Session Number/Title: Developmental Therapeutics
Session Date, Time: Monday, October 23, 2023, 12:00 – 13:00 CEST
Presenter: Noura Choudhury, M.D.
Location: Hall 8

About HPN328
HPN328 targets delta-like canonical Notch ligand 3 (DLL3) and is based on Harpoon’s proprietary Tri-specific T cell Activating Construct (TriTAC^®) platform designed to recruit a patient’s own immune cells to kill tumor cells. HPN328 is being evaluated as monotherapy in an ongoing open-label, multicenter two-part study to assess the safety, tolerability, and pharmacokinetics in patients with advanced cancers associated with expression of DLL3.

In March 2022, the U.S. Food and Drug Administration (FDA) granted Orphan Drug Designation to HPN328 for the treatment of small cell lung cancer (SCLC).

About Harpoon Therapeutics
Harpoon Therapeutics is a clinical-stage immunotherapy company developing a novel class of T cell engagers that harness the power of the body’s immune system to treat patients suffering from cancer and other diseases. T cell engagers are engineered proteins that direct a patient’s own T cells to kill target cells that express specific proteins, or antigens, carried by the target cells. Using its proprietary Tri-specific T cell Activating Construct (TriTAC^®) platform, Harpoon is developing a pipeline of novel TriTACs initially focused on the treatment of solid tumors and hematologic malignancies. Harpoon has also developed a proprietary ProTriTAC™ platform, which applies a prodrug concept to its TriTAC platform to create a therapeutic T cell engager that remains inactive until it reaches the tumor. Harpoon’s third proprietary technology platform, extended release TriTAC-XR, is designed to mitigate cytokine release syndrome. For additional information about Harpoon Therapeutics, please visit www.harpoontx.com.

Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as “expect,” “will,” and similar expressions (as well as other words or expressions referencing future events, conditions or circumstances) are intended to identify forward-looking statements. These forward-looking statements are based on Harpoon Therapeutics’ expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties that could cause Harpoon Therapeutics’ clinical development programs, future results, or performance to differ significantly from those expressed or implied by the forward-looking statements. Forward-looking statements contained in this press release include but are not limited to, statements about the expected timing, progress, and results of Harpoon Therapeutics’ clinical trials, including interim results of clinical trials and the safety and tolerability profile of product candidates, the association of interim clinical data and preclinical results with potential treatment outcomes and other statements that are not historical fact. Many factors may cause differences between current expectations and actual results, including unexpected safety or efficacy data observed during clinical studies, preliminary data, and trends may not be predictive of future data or results, may not demonstrate safety or efficacy, or lead to regulatory approval by the FDA or other regulatory agencies, clinical trial site activation or enrollment rates that are lower than expected, changes in expected or existing competition, changes in the regulatory environment, the uncertainties and timing of the regulatory approval process, the timing and results of unexpected litigation or other disputes, and the sufficiency of Harpoon Therapeutics’ cash resources. These and other factors that may cause Harpoon Therapeutics’ actual results to differ from those expressed or implied in the forward-looking statements in this press release are discussed in Harpoon Therapeutics’ filings with the U.S. Securities and Exchange Commission, including under “Risk Factors” in Harpoon Therapeutics’ quarterly report on Form 10-Q for the quarter ended June 30, 2023, and future filings by Harpoon Therapeutics. Except as required by law, Harpoon Therapeutics assumes no obligation to update any forward-looking statements contained herein to reflect any change in expectations, even as new information becomes available.

Contacts:
Harpoon Therapeutics
Ana Kapor
[email protected]