Dr. Victoria Kunene, a consultant medical oncologist at Queen Elizabeth Hospital Birmingham, is at the forefront of developing personalized mRNA vaccines for colorectal cancer. These vaccines represent a significant advancement in cancer treatment, offering both preventative and therapeutic potential.
NHS Cancer Vaccine Launch Pad Initiative
The NHS Cancer Vaccine Launch Pad (CVLP) initiative aims to accelerate access to mRNA personalized cancer vaccine clinical trials for cancer patients. This program supports treatment alongside chemotherapy and explores preventative measures. According to NHS chief executive Amanda Pritchard, these trials could offer a way to vaccinate individuals against their own cancer, potentially saving more lives.
On May 31, 2024, Dr. Kunene's team administered the first personalized vaccine against colorectal cancer in England as part of the CVLP. This trial focuses on patients with high-risk, stage two and stage three colon cancers, where 20-30% experience cancer recurrence despite post-operative chemotherapy.
How Personalized Vaccines Work
Unlike traditional vaccines, these personalized cancer vaccines are created after a cancer diagnosis. They target specific mutations found in a patient’s DNA. By analyzing the unique biological features of a patient’s tumor, the vaccines create an immune 'memory' to recognize and eliminate cancer cells, preventing recurrence after surgery or chemotherapy.
The process involves several phases:
- Screening for circulating tumor DNA (ctDNA): Patients undergo blood tests four to ten weeks post-surgery to detect ctDNA. Those testing positive are considered high-risk for recurrence.
- Bespoke vaccine manufacturing: For patients with detectable ctDNA, the tumor is sequenced to identify neoantigens. A minimum of five and up to 20 neoantigens are required to manufacture the vaccine.
- Vaccine administration: Patients are randomized to receive the personalized vaccine or standard of care (observation). Those in the vaccine arm receive weekly treatments for the first six weeks, then bi-weekly for a month, and finally every four to six weeks for up to 15 doses over a year.
Advancements in Colorectal Cancer Treatment
Dr. Kunene highlighted significant advancements in treating gastrointestinal cancers. Targeted therapies like trastuzumab for HER2-positive upper GI cancers and immune checkpoint inhibitors for PD-L1 positive or microsatellite-high tumors have become standard care. Additionally, drugs like bevacizumab and aflibercept, which are vascular endothelial receptor inhibitors, are used in combination with chemotherapy.
The Role of Circulating Tumor DNA
Recent studies indicate that patients with detectable ctDNA after cancer removal are at high risk of recurrence. This trial concentrates on this patient group, aiming to re-educate the immune system by generating specific T-cells against the cancer. The goal is to provide the immune system with the ability to recognize and eliminate any resurfacing cancer cells.
Integrating Old and New Therapies
Dr. Kunene also noted the importance of leveraging current technology to optimize the use of existing drugs, such as aspirin, which has shown improved outcomes in certain patient groups. The integration of genomic sequencing, circulating tumor DNA analysis, and artificial intelligence models is being optimized to improve survival and reduce treatment toxicity.
Trial Participation and Patient Support
Patients are informed of the possibility of not receiving the vaccine if randomized to the standard of care arm. However, they benefit from closer monitoring within the clinical trial, increasing the chances of early detection and prompt action if cancer recurs. The CVLP aims to improve access to these trials across the country, with the UK showing strong recruitment rates.
Future Impact
The success of the CVLP and personalized vaccine trials relies on the selflessness of patients willing to contribute to future advancements. Dr. Kunene emphasizes the coordinated effort required to deliver such a large-scale initiative within the NHS, expressing pride in the UK's leading role in these studies.
