The Road to a Cancer Vaccine: How Close Are We Really?

A cancer vaccine has always been elusive for medicine and science. Is this situation changing? Is hope rising over the horizon?

The Nanoparticle 'Super Vaccine' Developed by UMass Amherst

University of Massachusetts Amherst's scientists have successfully tested a new nanoparticle vaccine in mice, a vaccine to prevent melanoma, pancreatic cancer, and breast cancer. After the vaccine was given, 88% of the mice tested demonstrated recovery, and it also decreased cancer spread in all the mice tested. Prabhani Atukorale, an assistant professor at the university, led the team that developed this vaccine.

The nanoparticle-based cancer vaccine contains engineered nanoparticles that can trigger multipathway activation of the immune system. Melanoma peptides, an antigen specific to cancer, were combined with the nanoparticles, and this combination was found to prevent the spread of cancer.

This vaccine would need years of human trials before it can be approved, industrially produced and administered to those in need.

The mRNA Therapeutic Vaccine Developed by Everest Medicines

EVM14, the therapeutic vaccine for cancer developed by the Chinese company Everest Medicines, has got IND approval from China and the USA. It is a tumour-associated antigen vaccine, which can be used to treat multiple tumours. Administered as an injection, the vaccine comprises sterile mRNA-lipid nanoparticles (mRNA-LNP).

As news of cancer vaccine development continues to emerge from various scientific groups worldwide, the fear surrounding cancer is gradually subsiding. Yet, a vaccine for the entire range of cancers and patient populations could become accessible only a few more years forward in the future.

The Ovarian Cancer Vaccine

Oxford University scientists have developed a vaccine for ovarian cancer. This vaccine, OvarianVax, when available for use, will be able to teach the immune cells in our body to detect and attack ovarian cancer cells in the early stages of this disease. Prof. Ahmed Ahmed is the leading scientist behind this research. 

Trials for this vaccine have started. The significance of this development is that, once ready, this vaccine might eradicate ovarian cancer. Yet, this vaccine is still years away. 

Why Is a Cancer Vaccine Still a Mirage? What is Happening on the Research Front?

Catherine J. Wu, a cancer scientist, was awarded the prestigious Sjöberg Prize for her contribution to cancer research in February 2024. She is a professor of medicine at Harvard Medical School.  

She says the greatest challenge in developing a cancer vaccine is to teach our immune cells to selectively attack cancer cells and leave the normal cells unharmed. Cancer cells are not foreign objects entering our body like bacteria or viruses. These are our body cells acting destructively. They are a part of us, which is why our immune system does not identify them as threats when cancer arises.

Catherine’s research has identified certain peptides that are unique to cancer cells and can be easily detected by our immune system, a discovery which might be an initial step in creating a vaccine. Scientists named the peptides 'neoantigens'. 

These neoantigens pose a greater problem for vaccine development. They vary from one human body to another. Even patients with the same type of cancer have different kinds of neoantigens. Catherine and her team chose to adopt an alternative strategy to address this problem. 

Their innovative thinking resulted in the groundbreaking concept of personalised cancer vaccines.

The team tried to develop a vaccine consisting of 20 different peptides. When used in clinical trials, this vaccine cured the participants of melanoma. Trials are ongoing for melanoma, kidney cancer, ovarian cancer, certain types of chronic leukaemia, and glioblastoma. 

Catherine also co-founded a company, Neon Therapeutics, to conduct larger, industry-level clinical trials. Other vaccine companies have also come forward to conduct industry-funded trials. The outcomes of these trials are anticipated in two years. Hence, two years is the least timeframe we have to wait before we have a vaccine.

The ‘Nature’ Review of Cancer Vaccine Research

In 2022, ‘Nature’ published an article reviewing what was happening on the cancer vaccine research front. The article explains how cancer vaccine research evolved by experimenting with different types of antigens to be introduced into the patient’s body to get an effective immune response. These antigens included the whole tumour masses, isolated tumour cells, proteins, peptides, RNA, DNA, etc. The approaches primarily focused on four types of outcomes –

1. In situ – activate tumour sites to generate antigens

2. Ex vivo – tumour cells containing antigens are injected 

3. Personalised – introducing cancer-specific and person-specific mutations as antigens

4. Shared – introducing cancer-specific but non-person-specific mutations as antigens

The research and experiments that go into finding a cancer vaccine are multi-layered and complex because there are so many types of cancer, each type having different pathological structures in each individual. The article in 'Nature' discusses those complex processes and concludes that a cancer vaccine is just about at the next turn. 

The UK Vaccine Trials

In 2023, the UK government began collaborating with BioNTech, a private company known for its Covid-19 mRNA vaccine, the first among the Covid-19 vaccines. The government enrolled 10,000 people for a personalised mRNA cancer vaccine trial. The NHS has created a Cancer Vaccine Launch Pad to speed up the trials.

These are therapeutic vaccines rather than preventive ones. They were created based on insights scientists gained from the extensive use and advancement of immunotherapy drugs for cancer. 

These trials have brought renewed hope to numerous cancer patients in the UK. Each of the 10,000 participants will receive personalised cancer treatment, with the timeline extending until 2030.   

With the progress in cancer vaccine research, it is expected that an effective vaccine will be available by 2030. Upon its introduction, the vaccine will probably be personalised for each patient.