Genprex secures new IP for TUSC2 gene therapy in PD-(L)1 combo regimens

Gene therapy specialist Genprex, Inc. announced US Patent and Trademark Office (USPTO) award of a new patent covering the use of its lead candidate Reqorsa (quaratusugene ozeplasmid) in combination with programmed death-ligand 1 (PD-L1) antibodies, strengthening intellectual property protection around its immuno-oncology strategy. Separately, the European Patent Office granted a patent covering Reqorsa’s use in combination with programmed death-1 (PD-1) antibodies, with both patents providing exclusivity until at least 2037.

Reqorsa is a non-viral gene therapy comprising a plasmid expressing the TUSC2 tumor suppressor gene, encapsulated in lipid-based nanoparticles in a lipoplex formulation. TUSC2 is frequently deleted or under-expressed in lung cancers. By restoring TUSC2 expression in tumor cells, Reqorsa is designed to induce apoptosis, inhibit tumor cell proliferation and survival pathways—including PI3K/AKT, mTOR, and EGFR—and modulate immune signaling, potentially sensitizing tumors to immune checkpoint inhibition.

These mechanistic features have led Genprex to prioritize combination-based development strategies. The newly issued patents add IP protection around the company’s Phase I/II Acclaim-3 trial, which is evaluating Reqorsa in combination with the PD-L1 inhibitor Tecentriq (atezolizumab) as maintenance therapy in patients with extensive-stage small cell lung cancer (SCLC) who have previously received Tecentriq and chemotherapy (NCT05703971). Acclaim-3 has received US FDA Fast Track and Orphan Drug designations.

Genprex is also advancing Reqorsa in the Phase I/II Acclaim-1 study, evaluating Reqorsa with the EGFR inhibitor Tagrisso (osimertinib) in EGFR-mutant non-small cell lung cancer (NCT04486833). The Acclaim-2 study, assessing Reqorsa with the PD-1 inhibitor Keytruda (pembrolizumab) in non-small cell lung cancer, was terminated last year due to slow enrollment.

The Austin, Texas-based company is currently the only developer globally with an active clinical-stage program targeting TUSC2, as per publicly available data.