Early results are in on the latest trial of immunotherapy with ONCOS-102 and the news is good for pleural mesothelioma patients.
Norweigian drug maker Targovax released the news about ONCOS-102 earlier this week. The new drug is based on an oncolytic virus that targets mesothelioma cells. When the virus gets inside the cells, it triggers an immune response.
Early tests of immunotherapy with ONCOS-102 showed it helped mesothelioma chemotherapy work better. Now, a larger study appears to confirm the effect. The news could lead to new and better treatments for this intractable cancer.
What is an Oncolytic Virus?
An oncolytic virus is a virus that targets cancer cells. ONCOS-102 was designed to seek out mesothelioma cells. It is made out of an altered human adenovirus. Adenoviruses are responsible for most human respiratory illnesses.
The power behind immunotherapy with ONCOS-102 starts when the virus enters the mesothelioma cell. The virus replicates itself many times over, putting the immune system on high alert.
In the first, earlier phase of the trial, mesothelioma patients who received ONCOS-102 along with chemotherapy showed a “dramatic increase” in CD8+ T cells. The presence of these cells shows immunotherapy with ONCOS-102 is working.
Latest Trial of Immunotherapy with ONCOS-102
The latest trial is still ongoing but the early results are promising. The study involved 31 pleural mesothelioma patients. Twenty patients received ONCOS-102 along with standard chemotherapy. The remaining 11 patients only had chemotherapy.
According to early data, the drug combination appeared to stop mesothelioma from progressing for a median of 8.9 months. In the chemotherapy-only group, tumors came back in just 6.8 months.
Ninety percent of patients who had immunotherapy with ONCOS-102 responded to the treatment on some level. In 30 percent of patients, mesothelioma tumors either shrunk or disappeared. In the remaining 60 percent, mesothelioma was stable.
Pathologists looked at tumor samples from 15 of the patients in the ONCOS-102 group. Ten of them had a big increase in CD8+ T cells. Nine of them also had more PD-1 protein in their bodies. The results suggest that a checkpoint inhibitor to regulate PD-1 might improve ONCOS-102 response.
Reactions to the Early Results
“Although the data are preliminary and still maturing, it is encouraging to see signals of numerically improved median progression free survival in the ONCOS-102-treated group,” says lead author Luis Paz-Ares.
Professor Paz-Ares is Chair of the Medical Oncology Department at the Hospital Doce de Octubre, Madrid and Principal Investigator of the trial.
Dr. Magnus Jäderberg, Chief Medical Officer of Targovax, says the next step is a trial combining chemotherapy, immunotherapy with ONCOS-102, and a checkpoint inhibitor. The company is looking for a drug company to partner with in the next trial.
“Targovax announces encouraging data in mesothelioma study combining ONCOS-102 and standard of care chemotherapy”, January 21, 2020, Targovax news release, https://www.targovax.com/en/targovax-announces-encouraging-data-in-mesothelioma-study-combining-oncos-102-and-standard-of-care-chemotherapy/