US-based MabVax Therapeutics has started a Phase I clinical trial of HuMab-5B1, a fully human antibody, to treat patients with locally advanced or metastatic adenocarcinoma of the pancreas (PDAC) or other CA19-9 positive malignancies.
The CA19-9 target is reportedly expressed on more than 90% of pancreatic cancers and is a validated biomarker for the disease.
Last November, the company filed an investigational new drug (IND) application for this product and received authorisation from the US Food and Drug Administration (FDA) to proceed with the trial in December.
The primary objectives of the trial are to determine the safety, maximum tolerated dose (MTD), and the pharmacokinetics (PK) of HuMab-5B1.
Around 60 patients at multiple US centres will be enrolled in the trial, which will also evaluate tumour response rate and the duration of response of HuMab-5B1 as a single agent or in combination with a standard-of-care chemotherapy regimen.
This January, MabVax secured FDA authorisation for a second Phase I clinical trial with (Zr-89)-HuMab-5B1 as a positron emission tomography (PET) imaging agent in patients with pancreatic cancer.
The company noted that (Zr-89)-HuMab-5B1 combines a well-established PET imaging radiolabel (Zr-89) with the targeting specificity of the HuMab-5B1 antibody.
MabVax Therapeutics president and CEO David Hansen said: "Data generated in the early portions of these two Phase I trials could demonstrate important initial safety, PK and targeting specificity data of the antibody and signal the potential utility of the HuMab-5B1 antibody in the diagnosis and treatment of patients with this devastating disease.
"We anticipate reporting interim-study data from both trials in mid-year 2016.
"Additionally, we are excited about the potential applicability of our dual-product development approach in other cancers with HuMab-5B1, as well as with follow-on antibodies under development at MabVax."
The company noted that pre-clinical xenograft animal models revealed [Zr-89]-HuMab-5B1 to be a potential diagnostic agent for use with the HuMab-5B1 therapeutic product.
HuMab-5B1 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.
In pre-clinical research, the 5B1 antibody has shown efficacy in killing cancer cells for animal models of pancreatic, colon and small cell lung cancers.