Vaxiion Therapeutics today announced completion of the dose escalation segment of its ongoing multicenter Phase 1 study evaluating the safety and efficacy of VAX014 as monotherapy along with initiation of the Phase 1b dose expansion segment of the study. The dose expansion segment will implement an adaptive trial design to evaluate the safety and efficacy of VAX014 in combination with investigator’s choice of pembrolizumab or nivolumab in patients with solid tumors that have progressed on prior PD-1 blockade.

VAX014 is a novel, first-in-class, pan-tumor targeted, oncolytic immunotherapy using bacterial minicells and was specifically designed for optimal activity in STING and/or RIG-I positive tumors to overcome this biological limitation of oncolytic virus-based therapies. Provided as a sterile product, VAX014 eliminates the need for BSL-2 biocontainment, dramatically increasing patient access in comparison to oncolytic viruses.

Eighteen heavily pretreated solid tumor patients were treated with VAX014 across five dose levels in the dose escalation segment of the study. In the first nine patients, a single tumor was injected with a fixed dose volume whereas the last nine patients were allowed to have multiple tumors injected. Across dose levels, VAX014 was well tolerated as monotherapy and provided strong evidence of immune-mediated antitumor activity in both injected and non-injected tumors.

The Phase 1b dose expansion study (NCT05901285) is open and enrolling at eight sites across the United States and utilizes an adaptive trial design in patients with solid tumors who have progressed after prior PD-1 directed immune checkpoint blockade. Based on current enrollment rates, the Company anticipates enrolling up to 30 patients in the next 12 months.

“The monotherapy data with VAX014 is promising and I am eager to see how it performs in combination with pembrolizumab or nivolumab,” said study Principal Investigator Dr. Elizabeth Buchbinder of the Dana-Farber Cancer Institute. “Having a locally administered oncolytic immunotherapy option that doesn’t require special handling and biocontainment considerations has been really nice.”

“We are happy to report the initiation of the dose expansion segment of this ongoing study and are encouraged by the safety and efficacy data as well as the positive investigator and patient feedback from the dose escalation study.” said Vaxiion CEO, Matt Giacalone. “The Phase 1b dose expansion will continue to build on our hypothesis that VAX014 facilitates development of robust antitumor T cell responses to potentiate the effectiveness of immune checkpoint blockade.”

About Vaxiion

Vaxiion Therapeutics is a clinical stage, privately held, San Diego-based biotechnology company. Leveraging its closely related pair of proprietary first-in-class bacterial minicell-based delivery platforms, Vaxiion is developing and advancing novel, next generation oncology products. For more information about Vaxiion Therapeutics or this clinical trial, please visit www.vaxiion.com.

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