The U.S. Food and Drug Administration (FDA) has granted a Phase III status for Rexin-G? (Retroviral Expression Vectors Bearing an Inhibitory Gene), the first, and so far only, targeted gene delivery system developed to seek out and destroy metastatic cancer.
According to Erlinda Maria Gordon, M.D.Chief Medical Officer of Epeius Biotechnologies, “What this means, in terms of clinical development, is that the Rexin-G product, with its advanced GMP manufacturing, bio-processing, and final formulation, meets rigorous FDA standards for obtaining a marketing license in the future. Epeius Biotech can now proceed with its strategic, diversified Phase III drug development program for pancreatic cancer, osteosarcoma and soft tissue sarcoma.”
In addition to these high-priority programs, Rexin-G has demonstrated significant anti-tumor activity in chemotherapy-resistant breast cancer, hormone-refractory prostate cancer, ovarian cancer, squamous cell carcinoma, and certain hematologic malignancies, such as large B-cell lymphoma.
Mechanism of Action
Rexin-G is a matrix-targeted nanoparticle that seeks out the typical biochemical hallmarks of pathology (also called pathotropic targeting), accumulates to high levels in tumors, and delivers a cytocidal (lethal) gene construct: a dominant-negative construct of the human Cyclin-G1 gene, a pivotal cell cycle control element. The capsule containing the therapeutic dnG1 gene is based on a murine retroviral core, which is devoid of viral genes and has been rendered certifiably replication incompetent, meaning that it capable of delivering a therapeutic gene only once. once. The integral tumor-targeting function is unique, in that it is capable of penetrating primary and metastatic cancers, as well as cancers within the lymphatic system, with high efficiency, within a matter of hours, which represents the half-life of the active anti-cancer agent.
Rexin-G was granted accelerated approval for the treatment of all chemotherapy-resistant solid malignancies in the Philippines in 2007. In the U.S.A., Rexin-G received Orphan Drug Designation and market protections from the FDA for pancreatic cancer in 2003, followed by Orphan Drug Status for both osteosarcoma and soft tissue sarcoma in 2008. More recently, Epeius Biotechnologies completed a series of Phase I and Phase II clinical trials in the United States, establishing the thresholds for bioactivity and dose-dependent efficacy for Rexin-G against a number of otherwise intractable cancers, as well as the product’s overall safety over extended survival times and a notable lack of either safety issues or dose-limiting toxicities.
With these development-stage accomplishments at hand, the company is gearing up to open a series of clinical studies for both pancreatic cancer and sarcomas in North America, while continuing to advance the clinical utility and market development of Rexin-G worldwide.