What works with a cancer vaccine?
Personalized Cancer Vaccines: A Case Study of Tumour Regression, Survival and Immunity Monitoring: A Review of Various Approaches
The idea of giving a vaccine to people with cancer has been floating around for a long time. There is anticipation that the problem could be about to change after a number of fresh approaches.
The first step is to deliver antigens to immune cells called dendritic cells. These help the immune system by stimulating a response. In the past decade, several approaches have emerged1. One delivers a vaccine that helps people with the same type of cancer. Others, including those that make use of messenger RNA (mRNA) technology, are highly personalized to the unique neoantigens produced by an individual’s tumour (3). DnR cells can be injected into the body if they are loaded with cancer antigens or regenerated with cancer drugs if they are in situ.
Pancreatic cancer: In a phase I trial of a personalized mRNA vaccine, half of the participants developed T cells targeted to cancer neoantigens6. Recurrence-free survival in this group was longer compared with those who did not respond.
Lymphoma: A phase I/II trial of an in situ vaccine that combined radiotherapy with signalling molecules that mobilize and activate dendritic cells showed evidence of tumour regression in 8 of 11 people who were treated8.
The trials were unwieldy. Testing multiple combinations of agents makes clinical trials more complex. Timing when to give a vaccine is one of the complicating factors.
Immunity monitoring. Tracking the acquired immunity is necessary for assessing vaccine efficacy. T-cell monitoring is needed for cancer vaccines.
Scalability. logistical challenges could be posed by personalized cancer vaccines. Streamlining production will help keep costs down and availability high.
Personalized cancer vaccines are likely to pose logistical challenges as they need to be produced quickly, according to a study in the Journal of the National Cancer Institute. The study reviewed various approaches for personalized cancer vaccines including messenger RNA (mRNA) and direct-to- R (DnR) technology. Immunity monitoring is required for assessing vaccine efficacy, it added.