GT Biopharma, Inc. (GTBP) to Present Data on Next Generation TriKE (OXS-C3550)

The original anti-CD16-IL-15-anti-CD33 TriKE (OXS-3550) utilizes the inclusion of a modified Interleukin-15 (IL-15), a peptide that activates NK cells, while the “engager” further increases NK cancer-cell killing capabilities and improves their function in the tumor microenvironment (Vallera et al, 2016). OXS-3550 is expected to enter human clinical trials in 2018. OXS-C3550, the second-generation anti-CD16-IL-15-anti-CD33 TriKE, utilizes a modified anti-CD16 component while incorporating the wild-type IL-15.

The OXS-C3550 TriKE was developed following continued research with the TriKE platform at the University of Minnesota Masonic Cancer Center. As demonstrated in non-clinical models, this targeted immunotherapy directs immune cells to kill cancer cells while diminishing drug-related toxicity.

The TriKE platform technology can be viewed as a protein version of CAR-T; but unlike traditional CAR-T platforms, it is anticipated that TriKEs could service a much larger part of the cancer population at a fraction of the cost. TriKEs are an antibody platform that could be tailored to treat any form of cancer, liquid or solid tumors.

OXS-C3550 will focus on acute myeloid leukemia (AML), the most common form of adult leukemia with 43,000 new cases each year. These patients will require frontline therapy, usually chemotherapy including cytarabine and an anthracycline, a therapy that has not changed in over 40 years. Also, about half of these patients are likely to have relapses and require alternative therapies. In addition, OXS-C3550 could be used to treat myelodysplastic syndrome (MDS), which has about 20,000 new cases diagnosed each year with minimal current treatment options (Siegel et al, 2014). At a minimum, OXS-3550 is expected to serve as a relatively safe, inexpensive, and easy to use therapy for resistant or relapsing AML. From a biologic standpoint, it could also be combined with chemotherapy as frontline therapy.

GT Biopharma Chief Medical officer (CMO) Dr. Raymond Urbanski said, “The data on our second-generation TriKE, which will be presented at the upcoming ASH meeting, will be noticed by investigators in the field and will set the tone for all future discussions on the use of NK cells in the treatment of cancer. We believe the distinctions and potential benefits relative to other immunotherapies, including CAR-T, will become apparent.”

GT Biopharma Chief Executive Officer (CEO) Dr. Kathleen Clarence-Smith said, “In collaboration with the experts from the University of Minnesota Masonic Cancer Center, GT Biopharma continues to advance the search for next generation anti-cancer treatments, especially on novel ways to enhance the cancer-killing capabilities of NK cells. In my view, the potential for the success of this immunotherapy approach is substantial and the possibility of extending it to solid tumors gives us even added hope.”

GT Biopharma Executive Chairman Anthony J. Cataldo said, “This is another milestone achievement for the company as we continue to close out a very productive 2017.”

About GT Biopharma, Inc.: GT Biopharma, Inc. is a biotechnology company focused on innovative drugs for the treatment of cancer and nervous system diseases (Neurology and Pain) along with other unmet medical needs. GT’s lead oncology drug candidate, OXS-1550 (DT2219) is a novel bispecific scFv recombinant fusion protein-drug conjugate composed of the variable regions of the heavy and light chains of anti-CD19 and anti-CD22 antibodies and a modified form of diphtheria toxin as its cytotoxic drug payload. OXS-1550 targets cancer cells expressing the CD19 receptor or the CD22 receptor or both receptors. When OXS-1550 binds to cancer cells, the cancer cells internalize the drug and are killed due to the action of cytotoxic payload. OXS-1550 has demonstrated success in early human clinical trials in patients with relapsed/refractory B-cell lymphoma or leukemia. In addition, GT’s TriKE platform will address a number of cancer types. GT’s nervous system platform is focused on acquiring or discovering and patenting late-stage, de-risked, and close-to-market improved treatments for nervous system diseases (Neurology and Pain) and shepherding them through the approval process to the NDA. GT Biopharma’s neurology products currently include PainBrake, as well as treatments for the symptoms of myasthenia gravis, and motion sickness.