The American Cancer Society estimates that over 120,000 individuals are diagnosed of melanoma in the U.S. per year. A new drug that has shrank tumor in nearly a quarter of advanced melanoma patients in clinical trials has fortunately received the go signal from federal health regulators and could provide new treatment options for melanoma sufferers.
On Thursday, the Food and Drug Administration (FDA) gave the go signal for the use of the immuno-oncology drug Keytruda, or pembrolizumab, in patients with advanced melanoma who no longer respond to other therapies.
Melanoma is considered the most dangerous form of skin cancer that develops when unrepaired DNA damage to skin cells induces mutations that cause rapid multiplication of cells and formation of malignant tumors. The incidence of melanoma is largely attributed to exposure to ultraviolet radiation particularly from tanning beds and sunlight.
The approval of Merck & Co Inc.'s Keytruda marks the first time that U.S. health regulators gave the go signal for a new class of drug designed to help the body's immune system fight cancer. The drug works by blocking the protein called PD-1 to boost the body's immune system and fight cancer cells that escape from the body's defenses.
"This is not a drug that attacks the cancer directly. It enables the immune system to do the job that it is capable of doing," said Louis Weiner, from Georgetown University's Lombardi Comprehensive Cancer Center. "This is the first beachhead that's been taken. It's going to be all out assault on many different types of cancer."
The FDA said that in clinical trials, Keytruda has shrunk tumor of 24 patients diagnosed with advanced melanoma and whose conditions have worsened after receiving prior treatment.
"Keytruda's efficacy was established in 173 clinical trial participants with advanced melanoma whose disease progressed after prior treatment," FDA said in a statement. "In the half of the participants who received Keytruda at the recommended dose of 2 mg/kg, approximately 24 percent had their tumors shrink."
Keytruda, the sixth new melanoma drug that the FDA approved since 2011, will cost about $12,500, according to Merck, with the average duration of treatment for patients with advanced melanoma at just a little over six months.
Keytruda stimulates the body's immune system and for this, it can potentially result in severe immune-mediated side effects such as colitis and liver problems. Other side effects that were seen in clinical trials include cough, nausea, rash, itchy skin, fatigue and diarrhea.
