Identification and development of biomarkers for a specific immune response to L-BLP25, an antigen-specific cancer immunotherapy

Identification and development of biomarkers for a specific immune response to L-BLP25, an antigen-specific cancer immunotherapy

L-BLP25/Tecemotide (formerly also known as Stimuvax) is an antigen-specific cancer immunotherapy which is designed to stimulate a cellular immune response against the tumor antigen MUC1. In addition to clear signs of its clinical efficacy in lung cancer (NSCLC), to date there is still no reliable parameter to select patients who may benefit from treatment with L-BLP25, or a marker that predicts efficiency of the substance. In a Phase II clinical trial (“LICC” trial) being conducted by the University Medical Centre Mainz/Germany, the efficacy and safety of L-BLP25 is being investigated in patients with colorectal cancer after resection of liver metastases. In the current project, tumor and blood samples of subjects from this trial will be examined, with the aim of identifying biomarkers for L-BLP25. With its existing first-class expertise, the leading-edge cluster creates ideal conditions for explaining the mechanism of action of L-BLP25 and of identifying candidates for predictive biomarkers.

The search strategy for biomarkers encompasses seven complementary approaches. Since activation of MUC1-specific cytotoxic T-cells in patients after immunization with L-BLP25 is a critical step in the therapeutic approach, the presence of MUC1-specific T-cells in the blood is being analyzed by use of ELISpot assays. The immune suppression frequently exerted by tumors is studied by analyzing the phenotypes and frequency of MDSC (myeloid-derived suppressor cells) and regulatory T-cells in the blood as well as the presence of MDSC-effector-signal-pathways.

Auto-antibody signatures in plasma, micro-RNA-patterns in tumors and plasma, and presence of DNA-mutations/variations in patients’ tumors are also important candidates for biomarkers that are being investigated. In addition, the infiltration of tumor tissue by cells of the immune system may be crucial for the effectiveness of L-BLP25 and is thus being studied. The expression of MUC1 in the tumor and differences in cytokine/chemokine levels in the blood may also turn out to be relevant biomarkers.

The extensive search in various types of patient specimen should maximize the chance for identification of potential biomarkers. Blood, plasma and tumor tissue samples are collected during the trial in order to enable identification of candidate biomarkers by use of the broad search program described above, with the final goal to develop diagnostic tests for patient stratification and treatment monitoring.

Type 

  • Leuchtturmprojekt
Partner: 

Keywords 

  • Biomarkers
  • Cancer immunotherapy
  • Translational biomarker discovery

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