GreenPeptide Co., Ltd. is a biopharmaceutical venture company focused on developing novel “cancer immunotherapeutics.” Our lead product candidate is currently undergoing clinical trials. The therapeutic efficacy of cancer immunotherapy is based on using the patient’s own immune system to help fight against cancer. The use of immunotherapeutic agents boosts the body’s immune response by activating/controlling the normal immune machinery and modifying immune-related molecules to directly attack cancer cells and prevent cancer relapse, metastasis, and slow cancer progression. Cancer immunotherapy has different mechanisms of action to the three major therapies currently in use, namely surgical removal of cancer lesions, damaging cancer cells by targeted x-rays, or by the use of drugs and medicines, and has been called “the fourth treatment” for those who failed these conventional therapies. Cancer vaccines have emerged as one of the most promising therapeutic options.
Our business model covers drug discovery research and early clinical development of cancer immunotherapy; conducting of early-phase clinical trials; aiming for out-licensing agreement with pharmaceutical companies in and out of Japan for the late-phase clinical trials; and development, manufacturing, and launching the drugs as commercial products in Japan and abroad. We expect revenues from license fees (upfront fee at licensing agreement, development milestone payments, and royalties after launching) from these pharmaceutical companies.
In general, it takes more than ten years to develop a new drug. Our business model will enable us to create a broad range of license fees to be obtained from pharmaceutical companies, depending on the progress of development, such as upfront payment and development milestone payments even before regulatory approval of the product for manufacturing and marketing. After being approved, sales royalties would be obtained. We are also forming partnerships with pharmaceutical companies to gain funding for further development.
Our research on cancer immunotherapeutic seeds originally started as a venture project at Kurume University, a pioneer of cancer peptide vaccines in Japan since 1992. They started investigational clinical research on cancer peptide vaccines in 1998, which has since been completed. In 2003, our company was founded with transference of the patent rights from Kurume University. We have been developing vaccine formulation designs and are currently conducting a phase III clinical trial in prostate cancer patients. Our lead product candidate, ITK-1, a cancer peptide vaccine, was out-licensed to FUJIFILM Corporation prior to a phase III clinical trial in Japan. Currently, we are conducting the trial with development funds from FUJIFILM Corporation.
Cytotoxic T lymphocytes (CTLs) play a leading role in cancer immunotherapy. They recognize antigens derived from cancer cells that are presented on the surface of (antigen-presenting cell to target) cancer cells. In 1991, Dr. Thierry Boon and his colleagues in Belgium found that tumor-specific antigens were actually a short chain peptide of amino acids composed of only 9 (±1) amino acid residues and were recognized by CTLs. Those discoveries have clarified tumor immunology at the molecular level. As more cancer-specific antigens were identified worldwide, the development of cancer vaccines has been initiated.
In 1992, soon after the first identification of tumor-associated antigens by Dr. Boon’s group, a research group of the Department of Immunology at Kurume University started extensive exploratory research on tumor-associated antigens. In those days, Tumor cell lines were established from patients with cancer in Kurume University, tumor-derived cDNA libraries were constructed, and identified cancer antigen peptides were synthesized. The researchers at Kurume University incubated the cancer antigen peptide-loaded cells with tumor-specific CTLs to detect more potent peptide antigens for the reactivity of CTLs (measured by cytotoxic cytokine released from CTLs). Selected peptide antigens were further tested in blood samples from cancer patients for their ability to induce CTLs. Finally, selected peptide antigens have been administered to patients with cancer in investigational clinical studies at Kurume University, to select the most appropriate peptide antigens based on its potency to induce immune responses.
The antigenic peptides were chemically synthesized as the same sequences (9 or 10 amino acid residues) as those derived from human cancer antigens and were used as vaccines. Given that their amino acid sequence is of human origin, these peptides are considered safer than conventional anti-cancer drugs. Thus, they are expected to prolong patient survival with less adverse effects to their quality of life (QOL).
The development of our lead product candidate, ITK-1, a cancer immunotherapeutic vaccine, started with the succession of the research findings of Kurume University (Kurume, Fukuoka). We have promoted the translational studies as “research seeds from academia to industry,” including formulation design, pre-clinical studies, and early-phase clinical trials. Subsequently, ITK-1 was out-licensed to FUJIFILM Corporation. In June 2013, a phase III clinical trial of ITK-1 has been started in patients with prostate cancer in Japan.
This ongoing clinical trial is being conducted at multi-centers across Japan, in patients with castration-resistant prostate cancer who failed the conventional cancer therapies such as surgery, radiotherapy, hormone therapy, and/or chemotherapy prior to entry the clinical trial.
We have been conducting this study on behalf of FUJIFILM Corporation, which has provided funded for development. We will file pharmaceutical application for the approval of the manufacturing and marketing of ITK-1 if statistically significant efficacy is observed in the clinical trial. We will receive a milestone payment on the approval and sales royalties after marketing.
ITK-1 is a “personalized” cancer peptide vaccine. Optimal antigen peptides will be selected for individual patients from a set of 12 tumor-associated antigen peptides based on the results of immunity tests conducted using peripheral blood samples obtained from the patients prior to vaccination. Selected peptides will be administered as a cancer vaccine. “Personalized selection of drugs/antigen peptides” is intended to prolong patient survival with less impairment of their QOL.
Our second product candidate following ITK-1 is GRN-1201, a cancer immunotherapeutic vaccine that is adapted for a broader range of cancer patients in the United States. We have filed Investigational New Drug (IND) application with the United States Food and Drug Administration (FDA) in October, 2015. Now phase I trial has started in the US in patients with malignant melanoma, the first proposed indication for treatment with GRN-1201.