ONCOS-102 & Its Mechanism of Action

ONCOS-102 is a purposefully engineered human serotype 5 adenovirus optimized to induce systemic anti-tumor T cell response in cancer patients.

In order to make ONCOS-102 even more powerful, it includes three engineered characteristics:

  1. The adenovirus knob protein targeting the virus into the host cells is replaced with a protein from different adenovirus (serotype 3) to facilitate the specific entrance of ONCOS-102 into tumor cells.
  2. One of the genes affecting virus replication in the host cells is inactivated (Δ24 deletion). As a result the virus cannot replicate in normal cells, but can do so in tumor cells.
  3. A gene coding for GM-CSF, a drug stimulating the immune response, is inserted into the virus genome and expressed during the virus replication in the tumor cells.
ONCOS-102 structure

Mechanism of action


Local ONCOS-102 treatment induces a unique, systemic anti-tumor immune response in patients. The mechanism of action has been established by systemically studying samples collected from patients before and after treatment with ONCOS-102.

  1. Local administration of ONCOS-102 in the tumor creates a danger signal inducing the production of inflammatory cytokines
  2. ONCOS-102 particles infect tumor cells and result in immunogenic tumor cell death and release of tumor antigens and new ONCOS-102 particles in the tumor microenvironment
  3. The combination of the production of inflammatory cytokines, release of tumor antigens, release of new ONCOS-102 particles and production of the co-stimulatory molecule GM-CSF attracts antigen-presenting cells to the tumor. These cells take up tumor antigens (and also ONCOS-102 antigens)
  4. Antigen-presenting cells (such as dendritic cells) migrate to lymph nodes with the antigens.
  5. In the lymph nodes, antigens are presented to T Cells. As a result the T Cells are activated to recognize cells expressing those antigens.

Activated T cells attack and kill tumor cells expressing the specific antigens. The effect is systemic.

Evidence for ONCOS-102 Mechanism of Action

ONCOS-102_MoA_1v2 ONCOS-102_MoA_2v2 ONCOS-102_MoA_3v2 ONCOS-102_MoA_4v2 ONCOS-102_MoA_5v2