Researchers at Harvard University developed an effective personalized cancer vaccine that seems to have prevented early tumour relapse in 12 skin cancer patients. The vaccine targeted 20 tumour-specific proteins unique to each of the patients enrolled, keeping all free of cancer over 2 years after the trial.
Cancer is one of those unpredictable diseases that manifests itself in many shapes or forms, making it incredibly hard to treat with standardized medicine. Patients frequently undergo several damaging courses of medication before an effective treatment is found. This challenge has pushed researchers towards more creative approaches to tackle the disease, one of the more viable options being cancer vaccines. However, hundreds of vaccination attempts seemed to have done little for the patients until now.
Researchers led by Dr. Catherine Wu at the Dana-Farber Cancer institute in Boston developed a new personalized cancer vaccine that prevented 12 patients from going into early relapse, a common characteristic of skin cancer. Additionally, the treatment worked synergistically with another cancer drug by boosting the patients´ own immune system.
“We’re in this very exciting, new moment” for personalized cancer vaccines, said Dr. Wu, whose team presented their promising study at the annual meeting of the American Association for Cancer Research (AACR) in Washington, D.C.
The vaccine differs from previous single-antigen vaccines by targeting 20 neoantigens, tumour-specific mutated proteins unique to each of the patients. These neoantigens were identified by sequencing their genomes, allowing physicians to pinpoint the most vulnerable targets in each individual. Administering the right neoantigens thus activated a strong T cell response in the patients, allowing their adaptive immune system to take over and eliminate the cancer.
All of the patients who received the personalized vaccine remained cancer-free for more than 2,5 years after the trial and showed no signs of strong adverse effects. However, two patients with progressive cancer were given an additional immunotherapy drug called PD-1 checkpoint inhibitor, when the first signs of relapse started appearing. The powerful drug combination succesfully eliminated any remaining cancerous tissue.
However promising these preliminary results may seem, we have to be cautious when calling it a wonder drug just yet. As Drew Pardoll of Johns Hopkins University warns, “it´s way too early” to draw firm conclusions about whether the vaccines will extend the lives of cancer patients. But we can certainly keep our fingers crossed.
Learn more about personalized cancer vaccines in the video below:
By Luka Zupančič, MSc, University of Applied Sciences Technikum Vienna.