Cybrexa Therapeutics Announces First Patient Dosed in Phase 1/2 Clinical Trial


Cybrexa Therapeutics recently announced the first patient has been dosed in a Phase 1/2 clinical trial evaluating CBX-12 (alphalex-exatecan), the company’s lead therapeutic candidate.

The open-label, multicenter study will evaluate CBX-12 in patients with advanced or metastatic refractory solid tumors. The primary objectives of Phase 1 are to determine the safety and tolerability, maximum tolerated doses and dose limiting toxicities of CBX-12, and to establish the recommended Phase 2 dose of CBX-12. Two Phase 2 expansion cohorts will evaluate patients with platinum-resistant ovarian cancer and small cell lung cancer.

The secondary objectives of the study are to determine the PK of CBX-12 and of unconjugated exatecan, in plasma and tumor biopsies along with the evaluation of mechanistic biomarkers of CBX-12 which would allow Cybrexa to establish proof of mechanism for its platform.

“As the first clinical trial for a drug candidate for our platform, the Phase 1/2 trial of CBX-12 marks a major milestone for our company, as we seek to leverage our alphalex tumor-targeting platform to provide new treatment options for cancer patients,” said Per Hellsund, President and CEO of Cybrexa. “This trial will potentially validate the safety profile and efficacy shown in preclinical studies of CBX-12, and also help us identify its utility and inform subsequent Phase 2 trials.”

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 expression, which could greatly expand the addressable patient populations.

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 www.cybrexa.com.

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 1/2 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, visit www.cybrexa.com.