Promising results from a study on pleural mesothelioma were recently released. The study found when patients were treated with a new combination treatment, patients lived longer and had a better quality of life. The phase I clinical trial utilized a targeted cancer vaccine known as galinpepimut-S (GPS) and the immunotherapy drug Opdivo. SELLAS Life Sciences group is sponsoring the study at Memorial Sloan Kettering Cancer Center. Based on their findings, researchers have concluded that patients in advanced stages could still have a good quality of life.
All the patients in the study were previously treated and the treatment either stopped working or did not slow down the progression of tumors. The trial has found that there is an increased survival in patients when compared with other clinical trials. The goal of the trial is to expand the use of the treatment to as many people as possible, not just those in the clinical trial. Early results show a median overall survival of 10.5 months after the previous trial ended. This is much longer than the 20–24-week survival found in mesothelioma patients with relapsed or refractory mesothelioma. Six of eight patients started the trial at either stage 3 or 4. It is expected the median overall survival is going to improve as time passes and more results come in. The treatment combination created a median progression free survival of 11.9 weeks.
Currently, there is no approved second line treatment for pleural mesothelioma, so this combination treatment has the potential to help a lot of patients. Opdivo is currently a first line treatment alongside Yervoy for mesothelioma. The combination was approved in 2020. The vaccine has also been tested alongside Yervoy for ovarian cancer and is showing good results for this cancer as well. GPS is a treatment that targets the WT1 protein, which is a protein that is expressed in high quantities by certain cancer cells. It is not expressed by normal cells, so it is a prime target for an immunotherapy treatment. Immunotherapy is also a good option since standard chemotherapy does not work well when targeting WT1. There are only side effects from opdivo, which are already minimal. This treatment is showing that stage IV mesothelioma is not necessarily an immediate death sentence when the right treatment is utilized.
The FDA granted GPS Fast Track Status, which makes the normal 10-year drug review process faster. It also gives financial incentives to the developers. The FDA does this for unmet medical needs including hard-to-treat cancers like mesothelioma. GPS is also showing effectiveness as a single treatment for certain cancers. When paired with surgery, median survival was improved by 25 percent in mesothelioma patients. When the vaccine was paired with an almost complete resection of mesothelioma, the survival time was almost doubled. The vaccine’s effectiveness in active cancer cases is very promising because the typical response cancer vaccines create is not very good.