Vigil is intended to stimulate and enhance the body’s natural mechanism for recognizing and killing cancer cells. It utilizes the patient’s own cancer cells to create a fully personalized cancer immunotherapy.
Patient’s tumor tissue is removed surgically as part of the standard of care for most advanced cancers. The tissue is shipped on ice to our cGMP manufacturing facility where, in a two-day process, the patient’s cancer cells are genetically modified. Up to 12 doses of Vigil immunotherapy are produced for each patient.
The genetic modifications are achieved through the introduction of a proprietary gene plasmid into the patient's cancer cells. The plasmid carries the vectors of two genetic modifications.
The first gene sequence involves the introduction of a bi-functional shRNA targeting the knockdown of the enzyme furin. One of the functions of the furin enzyme is to convert immunosuppressive TGFβ1 and TGFβ2 into active isoforms. Thus, inhibiting furin production in the patient’s cancer cells results in the reduction in the expression of TGFβ1 and TGFβ2 in these cells.
The second gene sequence expresses Granulocyte Macrophage Colony Stimulating Factor, or GM-CSF, a potent stimulator of the immune system. It has been demonstrated that GM-CSF enhances surface antigen expression, making the cancer cells more visible to the patient’s immune system. GM-CSF also further stimulates the patient’s immune system by actively recruiting and maturing antigen-presenting cells, such as dendritic cells.
Vigil immunotherapy is then shipped for treatment into the intradermal layers of patient’s upper extremities once per month (either 3-week or 4-week cycle), for up to 12 doses.
When the cells are injected into the patient’s arm, modified autologous tumor cells are designed to activate the immune system. GM-CSF expression enhances cell surface antigen expression and recruits dendritic cells to the injection site; while the inhibition of TGFβ1 and TGFβ2 production allows cancer cells to now be “visible” to the patient's antigen-presenting cells (APCs).
Antigen-presenting cells (APCs) then follow the natural immune response by sampling the tumor cell surface antigens, followed by migration into local lymph nodes where they educate and activate T-cells against those cancer neoantigens. Circulating T-cells now are activated and enabled to fight the patient’s cancer.