Sonnet BioTherapeutics Announces Preclinical Data Supporting Its Bispecific Interleukin Candidates at the American Association for Cancer Research (AACR) 2022 Annual Meeting

PRINCETON, NJ / ACCESSWIRE / April 8, 2022/ Sonnet BioTherapeutics Holdings, Inc., (NASDAQ:SONN) a clinical-stage company developing targeted immunotherapeutic drugs, announced today that data from preclinical studies of the company's proprietary Fully-Human Albumin Binding candidates, SON-1010, SON-1210, and SON-1410, will be presented in a poster session at the American Association for Cancer Research (AACR) Annual Meeting 2022, April 8-13, in New Orleans, Louisiana.

"We are excited about these data that support tumor growth reduction following administration of both SON-1210 and SON-1410 in a B16-F10 melanoma model in mice," said John Cini, Ph.D. Chief Scientific Officer and Co-Founder of Sonnet BioTherapeutics. "Specifically, these new data elucidate the potential for transitioning tumors from being immunologically "cold" to clinically responsive and "hot". We look forward to dosing the first patient in the forthcoming clinical trial with our SON-1010 compound, an event that will set the table for our continued development of the SON-1210 and SON-1410 bispecific candidates."

Full data are available in the abstract titled, "An Innovative Human Platform for Targeted Delivery of Bispecific Interleukins to Tumors" and the accompanying poster, the top line highlights from which are as follows:

• Interleukins-12, -15, and -18 are among the most potent inducers of anti-tumor activity in animal models and have been evaluated in numerous clinical studies.
• Sonnet's bispecific drug candidates are constructed with IL-12 on the FHAB platform (SON-1010) and include IL12-FHAB-IL15 (SON-1210) and IL18- FHAB-IL12 (SON-1410).
• A "cold" immunosuppressive B16-F10 melanoma tumor model was used for comparing the efficacy of the bispecific candidates administered in a single intravenous (i.v.) dose.
• Dosing with either construct resulted in statistically significant tumor size reduction compared to placebo or native interleukin at a 5µg dose: 67% for IL12-FHAB-IL15 and 76% for IL18-FHAB-IL12.
• Optimal synergistic efficacy occurred with the IL18-FHAB-IL12 bispecific.
• These studies demonstrate that beyond the powerful anti-tumor effects of IL-12 evident in the monospecific IL12-FHAB, in the bispecific format, IL-12 can synergize with other cytokines to produce superior anti-tumor activity.

The abstract is available in the AACR Online Meeting Planner at www.aacr.org and on the Sonnet website at https://www.sonnetbio.com/technology/publications. Details of the poster presentation are as follows:

Title: An Innovative Human Platform for Targeted Delivery of Bispecific Interleukins to Tumors
Abstract Number: 4229
Session: Immunology
Presentation Type: Poster
Session Date and Time: Wednesday April 13, 2022; 9:00 AM - 12:30 PM
Location: New Orleans Convention Center, Exhibit Halls D-H, Poster Section 38
Poster Board Number: 9

About Sonnet BioTherapeutics Holdings, Inc.

Sonnet BioTherapeutics is an oncology-focused biotechnology company with a proprietary platform for innovating biologic drugs of single or bispecific action. Known as FHAB (Fully Human Albumin Binding), the technology utilizes a fully human single chain antibody fragment (scFv) that binds to and "hitch-hikes" on human serum albumin (HSA) for transport to target tissues. Sonnet's FHAB was designed to specifically target tumor and lymphatic tissue, with an improved therapeutic window for optimizing the safety and efficacy of immune modulating biologic drugs. FHAB is the foundation of a modular, plug-and-play construct for potentiating a range of large molecule therapeutic classes, including cytokines, peptides, antibodies and vaccines.

Forward-Looking Statements

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Sonnet Biotherapeutics Investor Contact:

Michael V. Morabito, Ph.D.
Solebury Trout
917-936-8430
mmorabito@soleburytrout.com

SOURCE: Sonnet BioTherapeutics, Inc.