GNPX 2017 Annual Report

10 Our preclinical and clinical data indicate that Oncoprex is well tolerated and may be effective alone or in combination with targeted small molecule therapies, thereby facilitating the action of both drugs, allowing use in expanded populations of patients who may benefit from advanced therapy regimens. Data have shown that when Oncoprex is combined with EGFR TKI therapy, such as erlotinib, in EGFR mutated resistant cancers, the combination therapy overcomes intrinsic and acquired therapeutic resistance by simultaneously inactivating the EGFR and the AKT signaling pathways to restore apoptotic signaling. Overcoming EGFR resistance in a clinical setting could provide a path for approval of Oncoprex for patients who do not have an activating EGFR mutation (90% of patients of American and European descent and 50% to 70% of those of Asian descent) and/or for patients who have an activating EGFR mutation but who have become resistant to erlotinib. Clinical and preclinical data indicate that Oncoprex, when combined with EGFR TKIs such as erlotinib and gefitinib, provides a synergistic effect that could also benefit the larger population of NSCLC patients who are EGFR negative (which means they are not expected to benefit from EGFR TKI drugs alone). Further, our data show that Oncoprex may re-sensitize EGFR positive patients who become resistant to, and therefore no longer benefit from, EGFR TKIs alone. Thus, Oncoprex may both significantly expand the benefit of EGFR TKIs to the majority of patients (90% of those of American and European descent and 50% to 70% of those of Asian descent) who do not have EGFR activating mutations and would therefore not otherwise be expected to benefit from EGFR TKI drugs, and also extend the usefulness and benefit of EGFR TKIs for the population of NSCLC patients who are EGFR positive, but who do not have the T790 mutation and who have become refractory to erlotinib, for whom there is currently no well-accepted standard treatment other than chemotherapy. Many currently approved cancer therapeutics target only single molecules or a single specific genetic abnormality related to driving the proliferation and survival of cancer cells. In contrast, Oncoprex works by targeting several molecules within the cancer cell to interrupt cell signaling pathways that cause replication and proliferation of cancer cells, to target and kill cancer cells, to block mechanisms that create drug resistance and to stimulate the natural immune response. Moreover, clinical and preclinical data show that Oncoprex works with other cancer drugs or their non-humanized equivalents, to produce more effective anti-cancer effects than either produces alone. In conjunction with these other drugs and equivalents, Oncoprex has been shown to mediate an anti-tumor response through up-regulation of NK cells, CD8+ T cells, and down-regulation of regulatory T cells, or Tregs, and PD-L1 receptors, activate alternative immune mechanisms with the potential to complement checkpoint inhibitors. Published data indicate that effectiveness of these kinase inhibitors and immunotherapy drugs is enhanced when they are combined with Oncoprex. Delivery System The Genprex immunogene therapy platform consists of anti-cancer genes encapsulated in nanovesicles delivered intravenously. The Oncoprex TUSC2 gene is encapsulated in a positively charged nanovesicle that binds to actively replicating (and therefore negatively charged) cancer cells, and then enters the cancer cell through selective endocytosis. These nanoscale vesicles differ significantly from liposomes historically used for drug delivery in that they are true particles encapsulating the therapeutic payload within a bilamellar lipid coat. Our collaborators at MD Anderson have optimized the characteristics of lipids including N-(1-(2,3- Dioleoyloxy)propyl)-N,N,N-trimethylammonium methyl sulfate, or DOTAP:cholesterol and a DNA plasmid expressing the TUSC2 tumor suppressor gene which form a spherical particle with a hollow center, nanoscale in size, which encapsulates the TUSC2 gene for delivery as Oncoprex. Operation of the Oncoprex TUSC2 Nanovesicle Delivery System The particle size is small enough to allow Oncoprex to cross tight barriers in the lung, but large enough to avoid accumulation or clearance in the liver, spleen and kidney. The cationic (positive) charge of the nanovesicle targets cancer cells, and direct nanovesicle fusion avoids target cell endocytosis. A Phase I clinical trial showed that intravenous Oncoprex therapy selectively and preferentially targeted primary and metastatic tumor cells, resulting in anticancer activity. The nanovesicles are non-immunogenic, allowing repetitive therapeutic dosing and providing extended half-life in the circulation.