Genprex Updates Agreement with University of Texas MD Anderson Cancer Center to Resume Patient Enrollment in Phase I/II Study Evaluating Oncoprex/Erlotinib Combination Therapy in Non-Small Cell Lung Cancer

Genprex, Inc. (NASDAQ:GNPX), a clinical stage gene therapy company developing a new approach to treating cancer based upon a novel proprietary technology platform, today announced that it has amended its agreement with The University of Texas MD Anderson Cancer Center to resume patient enrollment in its Phase I/II clinical trial evaluating the combination of the company’s investigational drug Oncoprex™ and erlotinib (Tarceva®) for the treatment of Stage IV non-small cell lung cancer (NSCLC).

Oncoprex is a TUSC2 gene encapsulated in a positively charged nanovesicle made from lipid molecules and injected intravenously, which can specifically target cancer cells and insert wild-type TUSC2 into cellular DNA, effectively increasing expression of the TUSC2 protein and promoting tumor cell death.

Previously announced interim data from nine patients from the Phase II portion of this Phase I/II clinical trial showed a disease control rate of 78%, with seven out of nine patients achieving stable disease or better, including one complete response. In a previous Phase I clinical trial at MD Anderson evaluating Oncoprex as a monotherapy, five of 23 patients with late-stage NSCLC achieved stable disease or better, with one durable metabolic response.

“We look forward to completing the Oncoprex/erlotinib trial and expanding the study of Oncoprex in combination with other targeted and immunotherapies in the future,” said Rodney Varner, Chairman and Chief Executive Officer of Genprex. “We believe the data from the more than 50 late-stage NSCLC patients treated to date provide persuasive evidence of Oncoprex’s anti-tumor effects and favorable safety profile.”

A subset of NSCLC patients (approximately 10% of NSCLC patients of North American and European descent and approximately 30% to 50% of NSCLC patients of Asian descent) carry an EGFR mutation that makes their tumors sensitive to tyrosine kinase inhibitors, or TKIs, such as erlotinib. However, even for these patients, tumor resistance to TKIs frequently develops within two years, resulting in eventual disease progression. While next generation TKIs show promise in targeting resistant EGFR positive tumors that carry a mutation known as T790M, only about one-half of EGFR positive patients (5% to 7.5% of all NSCLC patients of North American and European descent and 15% to 25% of NSCLC patients of Asian descent) carry the T790M mutation. This leaves a significant majority of NSCLC patients—those who are EGFR negative and those who are EGFR positive but have become resistant to erlotinib and do not have the T790M mutation—without a targeted therapy for their cancer.