A promising immunotherapy drug made from a deactivated cold virus has cleared another hurdle on its way to becoming a viable new treatment for malignant mesothelioma.
Scientists with the Norway-based company that makes ONCOS-102 presented their most recent mesothelioma research data to colleagues at a symposium hosted by the International Society of Stem Cell Research and the European Society of Gene and Cell Therapy in October.
These data all appear to point to the fact that ONCOS-102 may offer a way to improve mesothelioma survival without making patients sicker.
A New Approach to Mesothelioma Cancer
ONCOS-102 is made from an altered human adenovirus, a class of viruses that cause most human respiratory illnesses. It is specially made to seek out and enter mesothelioma tumors and other types of cancer cells.
Once inside a mesothelioma cell, ONCOS-102 has the ability to replicate itself, sending a genetic signal that stimulates an anticancer immune response. ONCOS-102 has been altered so that it is only capable of replicating inside cancer cells and cannot do so in normal cells.
In preclinical studies, mesothelioma-infected mice treated with the ONCOS-102 vaccine and standard pemetrexed-based chemotherapy experienced a significant slowing of the spread of their cancer. When the drug was given to human mesothelioma patients, the results were equally encouraging.
“The Phase I data showed a dramatic increase in tumor-infiltrating cytotoxic CD8+ T cells, innate immune system activation, and cancer specific CD8+ T cells in blood indicating system activation of the immune system,” writes Dr. Magnus Jaderberg, the head of research and development at Targovax.
Both types of immune system activation were associated with longer overall mesothelioma survival.
The Future of ONCOS-102 in Mesothelioma Treatment
The next step for ONCOS-102 in mesothelioma treatment is a Phase Ib/II trial, which started in June and is still recruiting patients.
The trial will test a combination of ONCOS-102 and standard pemetrexed-based chemotherapy to see if the immunotherapy drug can boost the effectiveness of chemotherapy. Even though chemotherapy is a primary treatment for people with mesothelioma, it is only marginally effective for most patients.
Targovax also has plans to test ONCOS-102 in combination with immune checkpoint inhibitors and other types of cancer therapies in several other hard-to-treat cancers including ovarian cancer, melanoma and prostate cancer.
Immune checkpoint inhibitors, which have also been the subject of mesothelioma research, help keep cancer cells from producing certain proteins that protect them from immune system attack.
“Combining ONCOS-102 with immune checkpoint inhibitors is an intriguing opportunity which we are actively exploring,” says Dr. Jaderberg.
“Targovax to present at the ESGCT/ISSCR STem Cells and Gene Therapy Symposium”, October 17, 2016, News Release, Targovax website
Jaderberg, M, “Adenovirus-based cancer immunotherapies: ONCOS-102, ONCOS-402”, Targovax website