In an early experiment, a vaccine that fits everyone has a promise to prevent return to the difficulty of the pancreatic cancers.
Pancreatic cancer is a special concern. the The rate of survival for five years is about 13 %And up to 80 % of pancreatic cancers may return.
“If you want to ask me what is the disease that most of them need to prevent repetition, I will say this,” said Dr. Zev Winberg, co -director of the University of California, Los Angeles, the oncology program in the digestive system, which participated in the re -trial of the clinical in the first stage.
The vaccine targets one of the most common genetic motives for cancer: KRAS genes.
Class mutations occur around A quarter of all types of cancerIncluding as much as 90 % of pancreatic cancers And about 40 % of colon and rectum cancers. Their spread makes the brochure mutations a great target for cancer treatments, but the mutations have long been impossible to target drugs.
To accomplish this, the vaccine uses short chains of amino acids called peptides that teach immune cells to identify and attack Cells with Brass mutations.
“The decisive step is to involve an immune response,” Winberg said.
Cancer vaccines are an increased search for research, but many of these vaccines are intended for the patient. This means that their tumor must be sequenced to create a specialized vaccine. However, the vaccine in the current study does not need to be customized and will be available outside the shelf.
Killing the remaining cancer cells
in The first stage experienceIt was published on Monday in the nature of medicine, Winberg and a team of doctors from all over the country who employed 20 people with pancreatic cancer and five colon and rectum cancer. (They also chose to include some colon and rectal cancer patients because KRAS mutations are also a popular and rectal cancer engine, and people with colon and rectum cancer driven by these mutations are more likely to be repeated, Winberg said.)
Everyone in the experiment had a brochure mutations and underwent standard therapy – usually chemotherapy and surgery – to remove the bulk of their tumors.
After surgery, blood tests showed that there are a lot of cancer cells that remained behind, referred to as the remaining microscopic disease, which is very common with pancreatic cancer.
“We are talking about microscopic cancer that we cannot see it in examination,” said Dr. Scott Kubitz, a professor of medical oncology in the digestive system at the Anderson Anderson Cancer Center in Houston.
These cells can move to another place in the body and grow into metilla tumors, which leads to the frequency of deadly cancer often. Chemotherapy can kill some of these cells, but some usually remain in the body.
“From a realistic point of view, if we want to kill each last cancerous cell and make people really treat, you need to involve the immune system,” said Stephanie Dogan, a professor of immunology and virus at the Dana Farper Cancer Institute in Boston. “We were really bad in obtaining an immune response in pancreatic cancer.”
After surgery, everyone in the trial got six doses of the experimental vaccine, called ELI-002 2p. He also received thirteen reinforced clips. The entire process took 6 months.
About 85 % -21 out of 25 participants-they installed an immune response to KRAS, and about two-thirds of these patients have an immune response that seemed strong enough to avoid continuous cancer cells.
Moreover, in nearly 70 % of people in the experiment, the vaccine seemed to raise an immune response not only to the brochure mutations, but to other tumor cell targets that were not in the vaccine. A few people were “very respondents” who launched an unnaturally strong immune response to the cells.
“These people got the best results,” Winberg said. His team is currently running randomly Stage 2 trial To test the durability of the vaccine and compare whether the vaccine is more effective than the level of care, which usually monitors the patient to repeat.
In the first stage experience, people with pancreatic cancer survived for 29 months on average and lived free of repetition for more than 15 months after vaccination.
Winberg said, referring to the cancers that can be removed by surgery.
A growing field
It was very difficult to make cancer vaccines, partly due to the fact that cancer cells have a lot of proteins themselves as healthy cells, making safe goals difficult to get them. Only recently, medical technology has made the steps needed by researchers to refine treatment. Dogan said that the technology of the repeated messenger and the sequence of genes has become the fastest and cheaper has brought the cancer vaccines to clinical trials.
Personal cancer vaccines appear as a promise in both pancreatic cancers and the colon and rectal homeland, but the cancer vaccine that suits everyone will make the treatment faster and cheaper. Previous experiments that use peptide vaccines have failed to prevent the recurrence of cancer. But peptides in the new vaccine, called fatty peptides, had nothing previously – tail.
“This tail sticks to the lymph nodes where the immune cells are activated,” Dogan said. “You need something to get the immune system, and it wasn’t just injection of combat cancer cells or peptides do not work well.”
The most advanced clinical trials will have to confirm the results of the first stage experience, but promising results have been seen in other cancer vaccine experiments and can pave the way for major breakthroughs preventing cancer. Memorial Sloan Kettering also works on A afternoon vaccine This targets the genes mutation in 95 % of people with acute sophisticated leukemia. Data from a vaccine experience, KRAS, published on Monday, showed that it is likely to target these mutations through non -personal vaccines, which the researchers have long believed.
“The fact that the long -term survival is truly associated with the response of T -cells indicates that the vaccine caused this,” referring to the specific immune cells that the vaccine activates. “The idea that you can really target exciting brochures.”