A drug that works on the immune system seems to help prolong the lives of patients with advanced lung cancer when given along with standard chemotherapy, a new study finds. But how exactly does this drug work to fight against cancer?
The study, which included more than 600 individuals, found that patients with a common form of lung cancer who received the so-called immunotherapeutic drug in combination with chemotherapy were 51 percent less likely over a 10.5-month period compared to patients, who received placebo and chemotherapy (the control group).
In addition, the median "progression-free survival," or the time patients went without theirs The disease that worsened was nearly nine months in the immunotherapy group, compared with five months in the control group.
The study, which was presented yesterday (April 1
Like the drug
The drug called pembrolizumab, sold under the brand name Keytruda, helps with immunization The system detects and fights cancer cells, according to Merck, the drug manufacturer. In particular, it makes the drug more difficult for cancer cells to "hide" from the immune system.
Normally, immune cells known as T cells recognize threats to the body, such as infectious diseases or even cancer. But cancer cells can hide from the immune system if they have a protein called PD-L1 on the surface. This protein says T cells stand up and not attack the cancer cells, according to Merck. The way PD-L1 does this is by binding to another protein on the surface of T cells, called PD-1, which acts as a kind of "off switch" and deactivates the T cells.
Pembrolizumab blocks this interaction between PD-1 and PD-L1, "thus allowing our own immune cells to destroy the tumor cell," Dr. Edwin Yau, an assistant professor of oncology at the Roswell Park Comprehensive Cancer Center in Buffalo, New York who was not involved with the study. "By sensitizing these tumor cells to the immune system, we not only see tumor shrinkage but also a persistent response as the immune system continues to monitor the presence of these tumor cells." [11 Surprising Facts About the Immune System]
However, Yau found that pembrolizumab in itself only affects a minority of patients. But in combination with chemotherapy, the drug is more effective.
"Therefore, the results of KEYNOTE-189 [the new study] are exciting because the addition of chemo to pembrolizumab seems to increase the number of patients who benefit from immunotherapy," Yau told Live Science.
The results are likely to change the standard treatment for patients with this type of lung cancer, known as metastatic non-quasibric non-small cell lung cancer. Non-small cell lung cancer, or NSCLC, is the most common form of lung cancer. "Metastatic" means that the cancer has spread beyond its original location, and "not acknowledging" means that the cancer does not begin in a type of lung cell called squamous epithelial cells. Most NSCLCs are not Mongolian.
Instead of chemo alone, patients with this cancer would receive immunotherapy early in the course of their treatment, along with chemotherapy, according to the new findings.
Nevertheless, the drug has side effects – especially in about 5 percent of patients in the immunotherapy group, acute kidney problems occurred, compared with 0.5 percent of patients in the control group. "The higher rate of kidney toxicity needs to be considered and monitored," Yau said.
There are still a few other questions left open, including whether patients with high levels of PD-L1 have already been found on their tumor cells. Benefits of this type of immunotherapy reap any additional benefits from chemotherapy, Yau said. "We continue to eagerly expect longer-term follow-up of this study," he said.
The study, which was published online April 16 in the New England Journal of Medicine, was commissioned by Drs. Leena Gandhi, director of the Thoracic Medical Oncology Program at the Perlmutter Cancer Center of the NYU Langone Health
Original article from Live Science .