Cybrexa Therapeutics To Present Data at ASCO 2023 Highlighting First-In-Human, Dose-Finding Study of Lead Candidate CBX-12

• Activity and Safety Profile Reinforces Potential of CBX-12 in Solid Tumors
• Four Objective Responses Observed in Breast and Ovarian Cancers with CBX-12
• Dose-Limiting Toxicity Identified as Myelosuppression

NEW HAVEN, Conn., May 25, 2023 (GLOBE NEWSWIRE) — Cybrexa Therapeutics, a clinical-stage oncology biotechnology company developing a novel class of tumor-targeting peptide drug conjugate (PDC) therapeutics, today announced that new data for its lead compound, CBX-12, a first-in-class investigational PDC, will be presented at the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting being held in Chicago on June 2-6. The maximum tolerated dose (MTD) for CBX-12 was established on two different dosing paradigms, with myelosuppression being the primary dose-limiting toxicity. In addition, treatment with CBX-12 resulted in four objective responses.

“We are encouraged by the promise of CBX-12, as it has continued to demonstrate multiple objective responses as a single agent, and the side effects, including myelosuppression, appear to be manageable,” said principal investigator, Anthony Tolcher, M.D., CEO, Founder and Director of Clinical Research, NEXT Oncology, a research institution that conducted this study along with Yale Cancer Center and University of Texas MD Anderson Cancer Center.

Among the single-agent antitumor activity demonstrated by CBX-12 in the study, one patient achieved a complete response in ovarian, and three achieved partial responses, two in breast and one in ovarian, per the RECIST 1.1 criteria. The study also evaluated the safety profile of CBX-12, and results highlight its potential to reduce the toxicity of topoisomerase I inhibition through its proprietary alphalex™ technology that enables intracellular drug delivery. Further, the MTD were established at 45 mg/m² for three consecutive days in a 21-day cycle and 60 mg/m² weekly.

“As we look toward initiating Phase 2 trials in breast, ovarian, colorectal, and gastric cancers, we are bolstered by the continued signs of safety and tolerability that we are seeing with CBX-12,” said Mike Needle, M.D., Chief Medical Officer, Cybrexa Therapeutics. “Importantly, the data demonstrate that the use of Cybrexa’s proprietary alphalex technology allows for higher dose administration compared to unconjugated exatecan.”

About the Presentation

Abstract title: CBX-12-101: A first-in-human study of CBX-12, an alphalex peptide drug conjugate (PDC) in patients (pts) with advanced or metastatic solid tumors

Presenting Author: Ildefonso Ismael Rodriguez-Rivera

Time and date: Saturday, June 3, 2023, 9:00 a.m. EST; Hall A

Abstract information: #3087; https://meetings.asco.org/abstracts-presentations/224760

About the Trial

The trial is a first-in-human study. Patient cohorts in the Phase 1 trial were treated with escalating doses of CBX-12 in a 3 + 3 design on three dosing schedules: 5x daily every three weeks (Part A); 3x daily every three weeks (Part B); and once weekly (Part C).

About the alphalex™ Technology Platform 

The Cybrexa alphalex™ technology is a novel antigen-independent, peptide-drug conjugate (PDC) platform that enables targeted delivery of highly potent anticancer treatments and aims to revolutionize the standard of care in oncology. The platform consists of a pH-Low Insertion Peptides (pHLIPs®) peptide, linker, and small molecule anti-cancer agent. pHLIP peptides are a family of pH-Low Insertion Peptides that target acidic cell surfaces. pHLIP was developed at Yale University and the University of Rhode Island, and is exclusively licensed to pHLIP, Inc., and Cybrexa is a sublicensee of pHLIP, Inc.

About Cybrexa

Cybrexa is a privately held clinical-stage biotechnology company pioneering novel antigen-independent tumor-targeting peptide drug conjugate (PDC) therapeutics. The company is led by a dynamic team of highly successful life science entrepreneurs and veteran drug development scientists. Cybrexa investors include Advantage Capital Connecticut, Connecticut Innovations, Elm Street Ventures and HighCape Capital. It is on a mission to create therapeutics that revolutionize the standard of care in oncology. Cybrexa’s robust pipeline aims to combat breast, ovarian, non-small cell lung cancer and a range of other tumors. Its assets are built on Cybrexa’s alphalex™ technology platform, which enables intracellular delivery of highly potent anticancer treatments. Cybrexa is based in New Haven, Conn. and was founded in 2017. For more information about Cybrexa, please visit www.cybrexa.com or follow us on LinkedIn and Twitter.

About the Cybrexa and Exelixis Collaboration Agreement

In November 2022, Cybrexa and Exelixis, Inc. announced they have entered into an exclusive collaboration agreement providing Exelixis the right to acquire CBX-12. This collaboration underscores Exelixis’ commitment to expanding its clinical pipeline building upon its biotherapeutics and targeted drug therapy expertise.

Investors Contact:
Stephen Basso, CFO/COO, Cybrexa Therapeutics 
475-655-7952 
stephen.basso@cybrexa.com

Media Contact:
Tara DiMilia, TellMed Strategies
908-884-7024
tara.dimilia@tmstrat.com