SAN DIEGO, CA, USA I September 19, 2016 I MabVax Therapeutics Holdings, Inc. (MBVX), a clinical stage immuno-oncology drug development company reported on the early progress of its lead therapeutic antibody program, MVT-5873, currently in a phase I clinical trial in patients with pancreatic cancer and other CA19.9 positive malignancies. This trial is designed to establish safety, a recommended phase II dose (RP2D), and evaluate pharmacokinetics of MVT-5873, both as a monotherapy and in combination with the current standard of care chemotherapy.  The site investigators for the phase I trial are monitoring patient blood chemistry and hematology for safety as well as disease status using the standard RECIST 1.1 criteria to evaluate tumor response rate and duration of response.  The trial was initiated in February of this year.  Three clinical investigation sites are currently enrolling patients:  Memorial Sloan Kettering Cancer Center and two research sites in the Sara Cannon Research Institute network. 

“To date 13 patients, most with stage 3 and 4 metastatic pancreatic cancer, have been enrolled after having exhausted all other standard of care therapies,” stated President and CEO J. David Hansen. “Based on assessments conducted with available unaudited data to date from these patients, we are seeing a pharmacokinetic profile for MVT-5873 that is similar to other monoclonal antibody therapeutics.  We are actively dosing patients and plan on generating sufficient safety data in this portion of the phase I trial to allow the initiation, during the fourth quarter of this year, of the second part of the phase I trial where MVT-5873 will be administered in front line therapy in combination with a current standard of care chemotherapy.”  

The company has been monitoring patients using the validated tumor biomarker CA19.9 for levels both pre and post dose of MVT-5873, being aware that increasing levels of this biomarker have historically been used as prognostic indicator of disease progression.  The company intends on providing a more comprehensive interim data analysis upon obtaining sufficient patient data before year-end.

“We are pleased to note that the dose levels already achieved in the MVT-5873 safety study now exceed the highest dose levels to be administered for the concurrent phase I trial of MVT-2163, the company’s companion PET imaging product that is also under way,” continued Hansen.  “In addition, the dose levels achieved in the MVT-5873 trial have also cleared the dose planned for the phase I trial of MVT-1075, the company’s radioimmunotherapy agent also intended to treat pancreatic cancer.  We remain on track for submitting the Investigational New Drug Application (IND) for MVT-1075 to the Food And Drug Administration (FDA) later this year, and would initiate the phase I trial in the first half of 2017 after receiving FDA authorization to proceed.”

About MabVax

MabVax Therapeutics Holdings, Inc. is a clinical-stage biotechnology company focused on the development of antibody-based products to address unmet medical needs in the treatment of cancer.  MabVax has discovered a pipeline of human monoclonal antibody products based on the protective immune responses generated by patients who have been vaccinated against targeted cancers with the Company’s proprietary vaccines.  MabVax’s HuMab-5B1 antibody is fully human and was discovered from the immune response of cancer patients vaccinated with an antigen-specific vaccine during a Phase I trial at Memorial Sloan Kettering Cancer Center, or MSK.  In preclinical research, the 5B1 antibody has demonstrated high specificity and affinity, and has shown potent cancer cell killing capacity and efficacy in animal models of pancreatic, colon and small cell lung cancers.  The antigen the antibody targets is expressed on more than 90% of pancreatic cancers making the antibody potentially broadly applicable to most patients suffering from this type of cancer.  MabVax’s two lead antibody clinical programs, currently in Phase I clinical trials, utilize HuMab-5B1 as a naked antibody (MVT-5873) and as an immuno-PET imaging agent (MVT-2163).  Additional information is available at www.mabvax.com.

SOURCE: MabVax Therapeutics