For most advanced ovarian cancers, the current treatment is a combination of surgery and chemotherapy. Initially, patient response to this treatment is good, but most patients relapse and eventually develop a resistance to platinum-based chemotherapy. At this stage, there are no other curative therapeutic options for these patients.
Researchers recently carried out a pilot clinical trial testing a personalized cancer vaccine, and published their results in Science Translational Medicine.
The vaccine they tested was a dendritic cell-based vaccine. Dendritic cells are responsible for presenting foreign material, such as cancer cells, to the immune system. It is these dendritic cells that are taken from the cancer patient and are then exposed to the patient’s own cancer cells by a specified process. This essentially primes the dendritic cells so that when they are reintroduced into the cancer patient via a vaccine, it facilitates a broader, more effective immune response to treat the cancer.
During the clinical trial, patients received the vaccine in combination with established cancer treatments of bevacizumab and/or cyclophosphamide. Researchers chose cyclophosphamide as they believe it would enhance vaccination, and bevacizumab was thought to be a good addition for immunotherapy. The researchers specifically designed this study to assess the feasibility and safety of this personalized vaccine in ovarian cancer patients.
The study found that patients who received the vaccine in combination with cyclophosphamide and bevacizumab demonstrated a longer overall survival than those patients who received the vaccine and bevacizumab alone. The researchers highlight that these results support their hypothesis that cyclophosphamide allowed better immunization—that is, it allowed the vaccine to work more effectively.
There are many limitations associated with these dendritic cell-based vaccines. One of the limitations is the difficulty in obtaining enough tumour material to produce the vaccine and the difficulty in manufacturing the vaccine itself.
However, the data from this study is encouraging and it emphasizes the need for further research on these personalized vaccines that can be used in combination with other treatments to facilitate a broader anti-tumour immune response.
Written by Jade Marie Evans, MPharm, Medical Writer
Reference: Tanyi JL et al. (2018). Personalized cancer vaccine effectively mobilizes antitumor T cell immunity in ovarian cancer. Available: https://www.ncbi.nlm.nih.gov/pubmed/29643231.
This article was published by Medical News Bulletin.