MAY 26, 2017 10:49 AM PDT

FDA Approved Cancer Drug Based on Mutation, Not Location

WRITTEN BY: Xuan Pham

For the first time, the US FDA approved a cancer drug for patients based on presence of genetic biomarkers. Whereas cancer drugs have been traditionally been approved based on the location of the tumor, Keytruda (pembrolizumab) is approved for cancer patients with genetic defects classified as “microsatellite instability” or “mismatch repair” deficiencies.

"KEYTRUDA binds to the PD-­1 receptor and blocks its interaction with PD-­L1 and PD-­L2, which helps restore the immune response." - Keytruda.com

"This is an important first for the cancer community," said Richard Pazdur, acting director of the Office of Hematology and Oncology Products in the FDA's Center for Drug Evaluation and Research and director of the FDA's Oncology Center of Excellence. "Until now, the FDA has approved cancer treatments based on where in the body the cancer started - for example, lung or breast cancers. We have now approved a drug based on a tumor's biomarker without regard to the tumor's original location."

Keytruda is a humanized antibody that works as a second-line immunotherapy agent to destroy the cancer. This drug targets the programmed cell death 1 (PD-1) receptor, a protein that’s responsible for preventing the immune system from attacking its own cells. Cancers can take advantage of this system by making its own proteins that bind to PD-1, which shuts down the body’s ability to kill the cancer. As an immunotherapy, pembrolizumab boosts the body’s ability to kill the cancer again. The drug is already approved for the treatment of several types of cancer, including non-small cell lung cancer, melanoma, and some head and neck cancers, and even mesothelioma.

But the new approval could significantly expand uses of this drug. In particular, Keytruda may now be used to treat any solid tumor as long as the patients have the indicated biomarkers: microsatellite instability-high (MSI-H) or mismatch-repair deficient (dMMR). These types of deficiencies are estimated to be present in about 4 percent of cancers, including colorectal, endometrial, and gastrointestinal cancers.

Notably, the drug’s new indication would expand access to cancer patients with solid tumors that have progressed despite treatment and for which there are no other therapy. For colorectal cancer, this means patients who have exhausted their chemotherapy defenses with drugs such as fluoropyrimidine, oxaliplatin, and irinotecan, Keytruda can be a new option.

“The FDA’s approval of this new indication for Keytruda further supports Merck’s commitment to helping people with difficult-to-treat cancers,” said Roger M. Perlmutter, president of Merck Research Laboratories, the drug’s manufacturer.

 

About the Author
  • I am a human geneticist, passionate about telling stories to make science more engaging and approachable. Find more of my writing at the Hopkins BioMedical Odyssey blog and at TheGeneTwist.com.
You May Also Like
OCT 17, 2019
Cancer
OCT 17, 2019
Why some cancers receive more research funding
In a new study from Northwestern Medicine, researchers analyzed which types of cancer receive the most and least amounts of research funding. Their results...
OCT 17, 2019
Immunology
OCT 17, 2019
Are Bacteria Fighting Cancer For Us?
Scientists at the Sanford Burnham Prebys Medical Discovery Institute found that the RNF5 enzyme, produced by a gene in gut microbes affects tumor growth.&n...
OCT 17, 2019
Cell & Molecular Biology
OCT 17, 2019
Investigating the Molecular Basis of Sex-related Differences in Cancer
There are sex-specific differences in the rate and lethality of various cancers....
OCT 17, 2019
Cancer
OCT 17, 2019
Antibiotic use associated with bowel cancer
From 2000–2010, global consumption of antibiotics rose by 35% up to 70 billion doses each year. Although doctors are more cautious to prescribe antib...
OCT 17, 2019
Cancer
OCT 17, 2019
Infant with leukemia saved by liver cancer drug
A young child just months old recently successfully received cancer treatment for an uncommon type of leukemia. The drug used in the treatment was not a ta...
OCT 17, 2019
Cancer
OCT 17, 2019
Can eating mushrooms reduce the risk of prostate cancer?
Now here’s a question: have you eaten your mushrooms yet today? Although mushrooms may not be one of the typically-touted snacks in the healthcare wo...
Loading Comments...