Genprex Secures Key U.S. Patent for Gene Therapy in Combination with PD-L1 Antibodies

AUSTIN, Texas – November 18, 2025 — Genprex, Inc., a clinical-stage gene therapy company, today announced that the United States Patent and Trademark Office (USPTO) has granted the Company a crucial patent. The patent provides intellectual property protection through 2037 for the use of its lead drug candidate, Gene Therapy, in combination with PD-L1 antibodies, such as Tecentriq® (atezolizumab).

Patent Strengthens Acclaim-3 Clinical Trial

The newly granted patent is directly applicable to the Company’s ongoing Acclaim-3 clinical trial, which is evaluating the combination of the Gene Therapy and the PD-L1 antibody Tecentriq in patients with extensive stage small cell lung cancer (ES-SCLC).

“We continue to build protection around our lead drug candidate, [Reqorsa®], and this new patent provides the necessary technology protection applicable to our Acclaim-3 clinical trial in small cell lung cancer,” said Thomas Gallagher, Senior Vice President of Intellectual Property and Licensing at Genprex. “This patent secures exclusivity for this drug combination for the treatment of cancer, preventing would-be competitors from making, using or selling this drug combination.”

Genprex previously secured patents for the Gene Therapy/PD-L1 antibody combination in the U.S. and Korea and is actively pursuing additional patent applications in Europe, Canada, Brazil, China, and Israel.

About Acclaim-3: Phase 1/2 Trial Details

The Acclaim-3 trial is a Phase 1/2 study evaluating the Gene Therapy and Genentech’s Tecentriq as maintenance therapy for patients with ES-SCLC. Patients eligible for the trial have previously received Tecentriq and chemotherapy as their standard of care initial treatment.

• Treatment: Patients will receive the combination until disease progression or unacceptable toxicity.
• Phase 1 Completion: The Phase 1 dose escalation portion successfully demonstrated that the Gene Therapy was generally well tolerated, with no dose-limiting toxicities.
• Phase 2 Expansion: The expansion portion is expected to enroll approximately 50 patients.
• Primary Endpoint: The trial’s primary goal is to determine the 18-week progression-free survival rate from the start of the maintenance therapy.
• Timeline: Genprex expects to complete enrollment of the first 25 patients required for an interim analysis in the first half of 2026.

The Acclaim-3 clinical trial has already received support from the U.S. Food and Drug Administration (FDA) through both Fast Track Designation and Orphan Drug Designation.