Tests for New Cancer Drugs Not Reliable Enough, Doctors Say

“Drugmakers including Bristol-Myers Squibb Co and Merck & Co are testing which patients will most benefit from new cancer treatments based on a protein found in their tumors, but that guide, known as a biomarker, may be too unreliable, researchers and health experts said.

“Bristol’s Opdivo and Merck’s Keytruda are both therapies designed to block a protein known as Programmed Death receptor (PD-1) that tumors use to evade the body’s natural defenses. Competitors Roche Holding, AstraZeneca and Pfizer also have similar drugs in an earlier stage of development. The drugmakers are conducting clinical trials that test patient tumors for a related protein called PD-L1.

“The new drugs are mainly aimed at patients with so-called solid tumors suffering from diseases including lung cancer and liver cancer. Lung cancer, the most common type, claims 1.8 million new cases each year worldwide. Sales of drugs to block PD-1 could reach $33 billion a year by 2022, according to Morningstar.”


New Class of Drugs Shows More Promise in Treating Cancer

“A new drug that unleashes the body’s immune system to attack tumors can prolong the lives of people with the most common form of lung cancer, doctors reported on Friday, the latest example of the significant results being achieved by this new class of medicines.

“In a separate study, researchers said they had found that a particular genetic signature in the tumor can help predict which patients could benefit from the immune-boosting drugs.

“The finding could potentially extend use of these drugs to some patients with colorectal cancer, prostate cancer and other tumors that have seemed almost impervious to the new drugs. Most of the substantial results so far with these expensive drugs have been in treating melanoma and lung cancer.

“ ‘If you have the signature, you should treat with these checkpoint inhibitors,’ Dr. Luis A. Diaz Jr., an associate professor of oncology at Johns Hopkins University and the senior author of the study on the genetic marker, said in an interview, referring to the new drugs.”


‘Immune Checkpoint’ Drugs Show New Promise for Treating Non-Small Cell Lung Cancer


It has become routine practice to prescribe targeted drugs to patients with metastatic non-small cell lung cancer (NSCLC), whose tumors harbor molecular alterations in EGFR, ALK, and ROS. However, the majority of patients with NSCLC have no targetable mutations and lack good treatment options. Enter immunotherapy drugs, specifically ‘immune checkpoint blockade antibodies,’ to which many refer simply as ‘anti-PD-1 drugs,’ or simply ‘PD-1 drugs.’ In this post, I provide some updates on the efficacy of anti-PD-1 and anti-PD-L1 drugs in lung cancer. Continue reading…


Immune Checkpoint Inhibitors in Melanoma: New Directions


The drugs pembrolizumab (Keytruda) and nivolumab (Opdivo) were approved by the U.S. Food and Drug Administration (FDA) in 2014 and 2015, respectively. These two competing blockbuster drugs are already changing the outlook in metastatic melanoma, previously considered to be a fatal disease. Known as ‘immune checkpoint inhibitors,’ they work by releasing ‘brakes’ on a patient’s own immune system, freeing it to attack tumors. In the wake of their success, researchers are now taking immune checkpoint inhibition in new directions. Continue reading…


Test May Show Merck Melanoma Drug's Success in Lung Cancer

“A simple protein test can help identify lung cancer patients who are likely to respond to Merck & Co.’s melanoma drug Keytruda, a trial found.

“Based on the findings, Merck has applied for U.S. Food and Drug Administration approval for the drug in lung cancer patients who have failed other therapies, Merck research chief Roger Perlmutter said in an interview. Keytruda is already approved for treating advanced melanoma.

“In the trial of 495 advanced lung cancer patients treated with Keytruda, researchers tested patients’ tumors for the presence of a protein that tumor cells can use to switch off an immune system response to the cancer.

“People with high levels of the protein, called PD-L1, were far more likely to experience substantial tumor shrinkage after being treated with Merck’s drug than those who had lower levels of the protein, according to results being presented Sunday at the American Association for Cancer Research meeting in Philadelphia.

“The result ‘is very compelling,’ said Roy Herbst, chief of medical oncology at Yale Cancer Center, which participated in the Merck trial. ‘This could tell us who should get this drug and who shouldn’t.’ ”


Merck Drug Keytruda Effective Against 3 Cancers

“One of the hot new cancer immunotherapy drugs, Merck & Co.’s Keytruda, strongly benefited patients with melanoma, lung cancer and mesothelioma, according to three studies presented Sunday at the American Association for Cancer Research conference in Philadelphia.

“One study, comparing Keytruda to Bristol-Myers Squibb Co.’s Yervoy, could give Merck a temporary advantage as the rivals battle for market supremacy and billions of dollars in annual sales from this new generation of drugs, which help the immune system destroy cancer cells. While research continues, the pace is quickening and big improvements in patient care regimens are likely fairly soon.”


Keutryda Shines in a Mesothelioma Study

“The PD-1 inhibitor pembrolizumab, a cancer immunotherapy drug, shrank or halted growth of tumors in 76 percent of patients with pleural mesothelioma, a rare and deadly form of cancer that arises in the outer lining of the lungs and internal chest wall, according to a new study from researchers in the Perelman School of Medicine at the University of Pennsylvania. Patients diagnosed with the disease, which is tied to exposure to asbestos, have a median survival rate of about one year.

“The findings will be presented on Sunday at the 2015 American Association for Cancer Research (AACR) Annual Meeting, being held in Philadelphia April 18-22.

“An international team of scientists from the United States, Europe, and the United Kingdom led by Evan W. Alley, MD, PhD, co-director of the Penn Mesothelioma and Pleural Program, found that of 25 patients administered the medication, seven (28 percent) experienced tumor shrinkage and the drug appeared to halt tumor growth in 12 patients (48 percent) . Four patients (16 percent) had disease that progressed, and two patients had not been assessed at the time of analysis. No patients discontinued treatment because of serious drug-related adverse events.

” ‘The 76 percent disease control rate in this set of patients previously treated for malignant pleural mesothelioma is very promising and represents a signal of efficacy in the treatment of this disease,’ said Alley. ‘Our team was also gratified that none of our patients had unexpected side effects, there were no patient deaths related to the treatment, and we managed all adverse events without discontinuing treatment.’ “


Keytruda Study in Lung Cancer Is Very Promising

“A new drug that boosts the immune system’s cancer-fighting potential is showing early promise for some patients with advanced lung cancer.

“The drug, marketed as Keytruda, was recently approved in the United States for treating advanced melanoma, but is not yet approved for lung cancer.

“Still, experts were encouraged by preliminary findings reported Sunday at the annual meeting of the American Association for Cancer Research in Philadelphia, and published simultaneously in the New England Journal of Medicine.

“In a study of nearly 500 patients with advanced lung cancer, those with high levels of a particular protein in their tumor cells responded well to the drug, researchers reported.

“Close to half of these patients saw their tumors shrink, and so far, the effect has typically lasted beyond a year.”


Is There a Future for Immunotherapy in Breast Cancer?


Lately, immunotherapy—treatment that helps the body’s own immune system fight cancer—has made frequent appearances in news headlines. Indeed, researchers have reported remarkable clinical trial results for a new class of drugs known as ‘immune checkpoint blockade drugs‘ in the treatment of metastatic melanoma, lung, and kidney cancers. Approvals from the U.S. Food and Drug Administration (FDA) for the drugs Keytruda and Opdivo for melanoma and lung cancer have quickly followed. However, it may be that immunotherapies won’t work for all cancers, but only for those considered to be ‘immunogenic’; that is, cancers that trigger activation of the immune system. Researchers are studying different types of breast cancer to determine whether they are immunogenic, and what that might mean for their prognosis and treatments. Continue reading…