Genprex presents positive preclinical data for lung cancer drug REQORSA at American Association for Cancer Research meeting

Genprex Inc (NASDAQ:GNPX) said its collaborators have presented positive preclinical data for the combination of REQORSA, the company's proprietary TUSC2 immunogene therapy, in combination with chemotherapy and immunotherapies for the treatment of non-small cell lung cancer (NSCLC).  These data were presented in two presentations at the 2021 American Association of Cancer Research (AACR) annual meeting, the company said. The TUSC2 gene is a tumor suppressor gene and is the active agent in REQORSA. “We are pleased to have these positive data that provide further support for the therapeutic potential of REQORSA in combination with immunotherapies and targeted therapies in NSCLC presented before an audience of the world’s leading cancer researchers,” Genprex CEO Rodney Varner said in a statement. READ: Genprex announces $25 million registered direct offering priced at-the-market The positive data is helpful for Genprex’s plan to launch a pair of clinical trials, Varner added. “These data are particularly encouraging as we look to initiate our upcoming combination Acclaim-1 and Acclaim-2 clinical trials of REQORSA in NSCLC,” Varner said. “We know that many patients inevitably develop resistance to immune checkpoint blockade therapy or EGFR-TKI therapy. These data show that REQORSA in combination with immunotherapies and targeted therapies may provide enhanced efficacy in NSCLC that has become resistant to these regimens, offering hope to a large patient population who currently has limited treatment options.” Acclaim-1 is a Phase 1/2 combination clinical trial using REQORSA combined with AstraZeneca’s Tagrisso (osimertinib) in patients with late-stage NSCLC whose disease progressed after treatment with Tagrisso. Acclaim-2 is a Phase 1/2 combination clinical trial using REQORSA combined with Merck & Company’s Keytruda (pembrolizumab) in NSCLC patients who are low expressors of PD-L1. The first presentation, titled “TUSC2 immunogene therapy enhances efficacy of chemo-immune combination therapy and induces robust antitumor immunity in KRAS-LKB1 mutant NSCLC in humanized mice,” showed that the triple combination of chemotherapy, immunotherapy (immune checkpoint blockade) and REQORSA demonstrated strong antitumor efficacy and induced robust antitumor immunity in KRAS-LKB1 (KL)-mutant NSCLC in clinically relevant humanized mice models, the company said. Humanized mice were first treated with REQORSA, immunotherapy nivolumab (Opdivo), or a combination of both, and the results showed synergistic antitumor activity with the combination.  Next, humanized mice were treated with REQORSA, immunotherapy pembrolizumab (Keytruda), or a combination. When REQORSA was added to the chemotherapy and immune checkpoint blockade combination, the regression in metastases regression was significantly greater than either REQORSA alone, REQORSA and pembrolizumab, or chemotherapy and pembrolizumab treatments. “KRAS is a frequent genomic driver in lung adenocarcinoma,” Genprex CEO Michael Redman said. “LKB1 (also known as STK11) is a distinct subgroup of KRAS-mutants and is the most prevalent genomic driver of resistance to PD-1 blockade in KRAS-mutant lung cancer.” The second poster, titled “Overcoming resistance to osimertinib by TUSC2 gene therapy in EGFR-mutant NSCLC,” showed that REQORSA in combination with targeted therapy osimertinib (Tagrisso) demonstrated synergistic antitumor efficacy in EGFR mutant osimertinib resistant NSCLC tumors in H1975-OsiR isogenic tumors, the company said. Researchers also found that the upregulation of PDK1 was associated with osimertinib resistance. Contact Andrew Kessel at andrew.kessel@proactiveinvestors.com Follow him on Twitter @andrew_kessel