After a century of setbacks in cancer treatment, a personalized mRNA cancer vaccine—developed jointly by Moderna and Merck—has offered a new ray of hope. This marks the first time a therapeutic cancer vaccine has shown signs of success in a late-stage trial, rather than just an early-stage one.
In a trial involving over 1,000 patients, the vaccine developed by US pharmaceutical companies Moderna and Merck reduced the risk of recurrence or metastasis (spread to other parts of the body) following surgery for localized melanoma. While full trial data has not yet been released, researchers and cancer specialists believe this success could herald a new era of “personalized” vaccines tailored to the specific characteristics of a patient’s cancer.
The Long-Awaited News Arrives via Phone Call
On the night of August 13, Stéphane Bancel, CEO of Moderna, was at a Lebanese restaurant celebrating a friend’s birthday. It was there that he received the long-awaited call: the clinical trial for the jointly developed Moderna-Merck cancer vaccine had been successful.
Bancel noted that the news reminded him of the time in late 2020 when results from Moderna’s COVID-19 vaccine trials were released. However, the moment of joy was short-lived; work on the next steps had to begin immediately after receiving the results.
Dean Li, President of Merck Research Laboratories, shared a similar sentiment. In his words, it was not merely a “moment of joy,” but a time to immediately start working on the path forward.
The Result of a Decade of Research
Behind this success for Moderna and Merck lies nearly a decade of research. The two companies formed a formal partnership in 2016 to develop cancer vaccines. Under the agreement, Merck invested $200 million in 2016 and an additional $250 million in 2022, with plans to share both research costs and future profits.
At that time, Merck’s cancer drug Keytruda was rapidly gaining popularity as a pivotal treatment in the emerging field of immunotherapy. This type of drug removes the natural barriers that prevent the body’s immune system from fighting against cancer cells.
According to officials from Merck’s research division, Keytruda demonstrated to scientists that the human immune system is capable of identifying cancer cells. However, cancer cells create various barriers to protect themselves; Keytruda helps eliminate those obstacles.
Subsequently, researchers sought various ways to further strengthen the immune system, though many attempts ended in failure.
Tal Zaks, Moderna’s former Chief Medical Officer, also worked on cancer vaccines for a long time. In his words, they faced failure repeatedly in the past. However, mRNA technology, the reduced cost of cancer genetic sequencing, and advancements in immunotherapy opened the door to new possibilities.
How will this vaccine work?
The new vaccine is named Intisomeran Autogene. Unlike conventional vaccines, it is not designed to prevent an infection; instead, it identifies specific genetic changes within the patient’s own cancer cells and trains the immune system to attack them.
In this process, the genetic characteristics of the patient’s tumor are first analyzed. Then, a personalized vaccine is created to target the specific mutations or genetic changes present in that patient’s cancer.
Earlier cancer vaccines typically attempted to target only one or two specific mutations. However, new mRNA technology has made it possible to target a much larger number of mutations simultaneously.
This vaccine can train the immune system to recognize up to 34 specific cancer targets. Consequently, even if one target fails to work, other targets can still identify and destroy the cancer cells.
Why was melanoma chosen?
Researchers initially selected melanoma because it involves a higher number of genetic mutations compared to many other types of cancer. Additionally, Keytruda has a proven track record of effectiveness against this specific cancer. The study involved patients who had undergone surgery to remove early-stage melanoma. The post-surgery interval provided researchers with the time needed to analyze the characteristics of the patients’ tumors and develop personalized vaccines, while also allowing sufficient time for the immune system to mount a response.
Researchers administered the vaccine in combination with Keytruda. Keytruda helps the body’s T-cells (immune cells) activate against cancer cells, while the personalized vaccine provides these T-cells with the specific “address” or target to identify those cancer cells.
Potential for Billion-Dollar Market Success
If the vaccine receives regulatory approval, both Moderna and Merck stand to gain significant commercial benefits. Approval in the United States is anticipated as early as next year.
The success of this vaccine is particularly crucial for Merck, as Keytruda’s patent protection is set to expire later this decade. Meanwhile, for Moderna, the cancer vaccine could open up new business opportunities following the decline in demand for its COVID-19 vaccine.
Moderna’s share price rose significantly following the release of the trial results. According to market analysts, the vaccine could generate annual sales exceeding $1 billion by 2030 and reaching approximately $3 billion by 2035.
Larger Trials Ahead
However, researchers still face a significant challenge. While the technology’s efficacy in cancers with high mutation rates—such as melanoma—has become somewhat clear, the major question now is whether the same approach will succeed in cancers with relatively fewer mutations, such as those affecting the lungs, kidneys, and pancreas.
Researchers are also exploring ways to enhance the vaccine’s effectiveness by conducting a more detailed analysis of the data from the melanoma trials.
Moderna CEO Stéphane Bancel’s remarks also hint at future developments; according to him, the current version is not the final iteration of mRNA-4157.
Thus, after a century of setbacks, this success has not only opened up the possibility of a new cancer vaccine but has also ushered in a new era of personalized treatments tailored to the specific genetic characteristics of each patient’s cancer.
