Its lead T-Cell Engager HCW11-018b is shown to penetrate into the tumor microenvironment with potent and antigen-specific anti-pancreatic cancer activities

IND application expected to be filed in first half of 2027 to seek authorization for clinical study in patients with pancreatic cancer

Poster presented at the American Association of Cancer Research Annual Meeting 2026

MIRAMAR, Fla., April 27, 2026 (GLOBE NEWSWIRE) -- HCW Biologics Inc. (the "Company" or "HCW Biologics"), (NASDAQ:HCWB), a clinical-stage biopharmaceutical company developing transformative fusion immunotherapeutics to support or treat diseases promoted by chronic inflammation announced today major development regarding its tetra-valent, second-generation T-Cell Engager Program (the "Big BiTE") based on its TRBC platform technology, was presented at the poster session at the American Association of Cancer Research ("AACR") Annual Meeting 2026, which took place from April 17 – 22, 2026 in San Diego, California.

HCW11-018b, the lead candidate of the "Big BiTE" program, is a tetra-valent T-cell engager designed to enhance anti-tumor activities and tolerability to treat a wide spectrum of solid tumors. The Company's preclinical data showed HCW11-018b could significantly shrink well-established tumors and prevent cancer metastasis in xenograft animal models with broad coverage for human solid tumor indications.

The new data in the poster has revealed the mechanism of action that drives these results. HCW11-018b utilizes Cis-binding (or cis-interaction) to regulate immune cell reactivity that masks the receptors which prevent trans-binding and inhibit membrane flexibility. The data showed that HCW11-018b is only activated within the tumor microenvironment, which is expected to increase the efficacy and tolerability of this tetra-valent T Cell Engager against human tumor cells.

Dr. Hing C. Wong, the Company's Founder and Chief Executive Officer, stated, "HCW11-018b exhibits remarkable anti-tumor activities with high tolerability in animal models. With its streamlined GMP manufacturing process, the Company is vigorously -pursuing the clinical development path for solid tumors with particular focus on pancreatic and ovarian cancer. The IND application is projected to be filed in the first half of 2027."

The poster, entitled, "An innovative approach to improve bispecific T-cell engagers for solid tumor therapy," was presented by Dr. Wong at the AACR Annual Meeting 2026. The poster is available on the Company's investors' website in the following link: https://investors.hcwbiologics.com/events/event-details/development-hcw11-018b-t-cell-engager-innovative-approach-improve-bispecific.

About HCW Biologics:

HCW Biologics Inc. (the "Company") (NASDAQ:HCWB) is a clinical-stage biopharmaceutical company developing transformative fusion immunotherapeutics to support or treat diseases promoted by chronic inflammation, including autoimmune diseases, cancer, and senescence-associated dysplasia. The Company's immunotherapeutics represent a new class of drugs that it believes have the potential to fundamentally change the treatment of proinflammatory and senescence-associated diseases and conditions that are promoted by chronic inflammation --and in doing so, improve patients' quality of life and possibly extend longevity. A key aspect of the Company's clinical development and financing strategy is to focus on its business development programs. To date, the Company has entered into two licensing agreements in which it has licensed exclusive, worldwide rights for some of its proprietary molecules. See the Company Pipeline at https://hcwbiologics.com/pipeline/.

Forward Looking Statements:

Statements in this press release contain "forward-looking statements" that are subject to substantial risks and uncertainties. These statements are made under the "safe harbor" provisions of the U.S. Private Securities Litigation Reform Act of 1995. Forward-looking statements contained in this press release may be identified by the use of words such as "anticipate," "expect," "believe," "will," "may," "should," "estimate," "project," "outlook," "forecast" or other similar words and include, the actual success and potency of the Company's TCE-based TRBC fusion molecules; the ability of HCW11-018b to enhance anti-tumor activities and tolerability and treat a wide spectrum of solid tumors, including pancreatic cancer; the belief that the primary mechanism of action underlying HCW11-018b is cis-binding; the tolerability and efficacy of HCW11-018b against cancer and the translation of this preclinical data into the clinic. Further, certain forward-looking statements are based on assumptions as to future events that may not prove to be accurate. Factors that could cause actual results to differ include, but are not limited to, the risks and uncertainties that are described in the section titled "Risk Factors" in the annual report on Form 10-K filed with the United States Securities and Exchange Commission (the "SEC") on March 31, 2026 and in other filings filed from time to time with the SEC.

Company Contact:

Dr. Peter Rhode

Chief Scientific Officer and Vice President of Clinical Operations

HCW Biologics Inc.

PeterRhode@HCWBiologics.com

HCW Biologics Delivers a Major Update for its T-Cell Engager Program Revealing Mechanism of Action and Validating Tissue Factor as Target for Treatment of Solid Tumors