Cybrexa Therapeutics Reports Positive Results from GLP Toxicology Study of Lead Candidate CBX-12 (alphalex™-exatecan)

– No Unexpected Safety Findings During the Course of the Study –

– On Track to File an IND in the First Quarter 2021 and Commence Phase I Trial by Mid Year 2021 –

NEW HAVEN, Conn., Jan. 28, 2021 (GLOBE NEWSWIRE) — Cybrexa Therapeutics, an oncology-focused biotechnology company developing a new class of therapeutics through its alphalex™ Peptide Drug Conjugate (PDC) tumor targeting platform, today announced that it has completed the GLP toxicology study of its lead candidate, CBX-12. The positive results for this study serve as a guide for dosing regimen for the planned Phase I trial of CBX-12 as Cybrexa intends to file the IND during the first quarter 2021.

“The successful completion of the GLP toxicology studies is an early, yet significant milestone in the development of our lead candidate CBX-12, a highly potent alphalex PDC conjugate that we believe has the potential to impact several types of solid tumors, both as a monotherapy and in combination with PD-1 inhibitors and other immuno-oncology drugs,” said Per Hellsund, President and CEO of Cybrexa. “Additionally, the study results are relevant to the development of our other pipeline candidates, as they suggest the utility of our alphalex PDC tumor targeting platform for targeted intracellular drug delivery, independent of surface antigens.”

In the GLP toxicology studies CBX-12 was delivered via IV infusion, and based on multiple parameters, including mortality, clinical observations, body weights and food consumption, the results established a significant therapeutic index of ~20X over exatecan for CBX-12. Additionally, in accordance with the FDA feedback from the pre-IND meeting, Cybrexa completed a rodent respiratory safety pharmacology study with no notable clinical observations, as well as a hemolytic potential and plasma compatibility study with no hemolysis or plasma incompatibility observed.

CBX-12 is a novel treatment for solid tumors that includes a highly potent topoisomerase I inhibitor payload that is in the same class as the payloads used by antibody-drug conjugates (ADCs) ENHERTU® and TRODELVY™. In contrast to these ADCs, CBX-12 is able to target cancer cells independent of antigen overexpression, which should greatly expand the addressable patient populations.

About the alphalex™ Technology Platform
The Cybrexa alphalex™ technology platform – which consists of a pHLIP® peptide, linker, and small molecule anti-cancer agent (payload) – enables antigen-independent targeting of tumors and intracellular delivery of highly potent anticancer therapies, creating therapeutics that can revolutionize the standard of care. 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. alphalex™ represents the disruptive next generation in tumor targeting. View a video of the mechanism of action of the technology at

About Cybrexa
Cybrexa is a privately-held biotechnology company dedicated to developing next-generation tumor-targeted cancer therapies using its alphalex™ platform. The Company’s lead candidate, CBX-12, an alphalex™-exatecan conjugate, is expected to enter Phase I/II in 2021 in advanced solid tumors. Cybrexa also has other preclinical toxin conjugate programs as well as synthetic lethality programs. Cybrexa was founded by physician-scientists and has an experienced management team that has built numerous successful life sciences companies. For more information about Cybrexa, please visit


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