A “cure for cancer” might be too ambitious, but recent results in skin cancer vaccine trials are injecting hope into the battle against it. Known as mRNA-4157 (V940), the vaccine was recently given to a man named Steve Young — a melanoma survivor and one of the first patients to receive the new treatment.
But what is this vaccine, how did it come about and what should people worried about cancers like melanoma expect for the future?
How Does the Vaccine Work?
The recent study is a phase III trial and follows a successful phase II trial — in which “vaccines dramatically reduced the risk of the cancer returning in melanoma patients,” reports The Guardian. It’s not often you see the word “cure” being thrown around, but when melanoma patients have had surgery to remove the initial skin cancer, it’s hoped the vaccine will be a potential life-saver through preventing its spread.
“This is one of the most exciting things we’ve seen in a really long time,” said Dr. Heather Shaw, the trial’s national coordinating investigator. She pointed out its ability to work as a personalized tool for each patient and respond to each patient’s specific genetics “This is a really finely honed tool…the patients are really excited about them.”
The vaccine itself is individualized, functioning by triggering a patient’s immune system to fight back against the patient’s specific cancer and tumor. The implications extend beyond the return of melanoma and could have promising benefits to patients with other cancers as well.
By targeting “tumor neoantigens,” or the specific markers of each patient’s particular tumor, the vaccine can essentially alert the immune system to the presence of the tumor and help it fight it off naturally with an anti-tumor immune response.
What Hopes Do Doctors Have for this New Treatment?
Given the success of the second stage of the trials, researchers and doctors alike seem optimistic that the new treatment can have a powerful impact on cancer treatment. This optimism comes from the raw numbers. The phase II trial data, published last December, found that those who received the treatments (in addition to the immunotherapy Keytruda) were almost half (49 percent) as likely to die or have their cancers return after three years as those who were only given the drug.
According to Dr. Shaw, that means this treatment could be a “gamechanger.” Especially worth noting is the fact that it has tolerable side effects. Simply put, at this stage, the vaccine appears to have minimal side effects while helping the body’s natural immune response fight off cancer more efficiently. Solutions like that can mean incredible new hope for people struggling with the disease.
Experts told Sky News, for example, that these trials are “one of the most exciting developments in modern cancer therapy.” Historically, a major challenge in the fight against cancer has been the fact that everyone’s immune response is different. But that’s why this new bespoke approach to cancer is so effective — the vaccine helps the body create its own custom immune response to fight off tumors.
There are two reasons this approach is so powerful:
- A targeted immune response: Some cancer therapies can be effective, but in a less targeted way. For example, radiation therapy can shrink tumors. But this vaccine which creates a targeted response by the body’s own immune system is generally far more effective.
- Lack of side effects: With the immune system approach, the body is working as designed: detecting and destroying foreign cells that pose a threat to the body. This also means that there aren’t the more advanced side effects of other methods that use a less-targeted approach and therefore damage the body’s healthy cells as well as the cancer itself.
The Challenge of the Immune Response in Cancer Therapies
The immune system has a critical role in recognizing and eliminating abnormal cancer cells, with the problem being that cancer cells don’t always stimulate the immune response a patient requires. Rather than fighting off the cancer, our immune system can sometimes be tricked into ignoring its growth.
But there’s been success in recent years in developing cancer therapies that boost the immune system’s power to 1) recognize cancer cells and 2) destroy them. Known as “cancer immunotherapies,” this approach is showing a lot of promise. The immune system can target cancer cells like no other intervention, helping eliminate the cancer without damaging other healthy cells in the patients’ bodies.
Immunotherapy has had to overcome its own set of challenges. For instance, there’s the obstacle of downregulation of antigen presentation. Because cancer cells can decrease the expression of molecules presenting antigens (foreign or abnormal proteins in the body), immune cells may not be able to recognize when there’s a problem. This is why cancer can sometimes thrive despite the immune system’s best effort to keep the person healthy. The immune system essentially doesn’t recognize that cancer is there.
That’s one reason this new vaccine is so promising. Targeting tumor neoantigens means the vaccine gives the immune system something of an alert, warning that there’s something in the body that doesn’t belong there. The immune system can then begin targeting the cancer, working to destroy it while preserving the health of the body.
A Look to the Future
What does the future hold for treating this disease? Now that the trials have moved to the third stage, there is a lot of promise here. The treatment already demonstrated its effectiveness in the second phase but In the third round of the trial, it should get more direct, real-world practicality and reveal just how well this therapy can help fight off cancer — giving new hope to cancer sufferers who need a stronger immune response to eliminate the cancer and prevent it from returning.
