Galinpepimut-S (WT-1 Analog Peptide) Vaccine in Malignant Pleural Mesothelioma After Combined Modality Therapy

The doctors are testing galinpepimut-S, a Wilms Tumor-1 (WT1) vaccine, to see if it delays or prevents the mesothelioma from growing back after surgery. WT1 is a protein in cancer cells that regulates gene expression and causes cell growth. Mesothelioma tumors generally have high levels of WT1.This study was originally designed to have two treatment groups. One group received non-specific immunotherapy with medications called Montanide and Sargramostim (Granulocyte Macrophage Colony Stimulating Factor, GM-CSF). Enrollment to this group has stopped The other group, which continues receives more specific immunotherapy with galinpepimut-S plus Montanide and GM-CSF. Both Montanide and GM-CSF are commonly given along with vaccines because they have a general effect in boosting the immune response. Some researchers believe that this general increase in the immune system may have some effect in treating cancer. Some studies using GM-CSF with melanoma vaccines have suggested that it could lessen the effects of the vaccine. The addition of the WT1 proteins makes this therapy more directed to mesothelioma. The combination of galinpepimut-S with Montanide and GM-CSF has been tested in a prior trial including 9 patients with advanced mesothelioma. In that trial, the vaccine was safe and caused an immune response.