The first FDA-cleared drug for the treatment of Merkel cell carcinoma (MCC) is now available after clinical trials found that patients, mostly pre-treated with chemotherapy, responded to the drug for as long as one year.
The drug Avelumab (brand name Bavencio®), belongs to a class of drugs called checkpoint inhibitors. Checkpoint inhibitors counteract cancer cells’ ability to suppress immune systems by tricking the body’s checkpoint molecules into treating cancer cells as healthy cells. Avelumab alerts the body to the presence of dangerous cancer cells and directs the immune system to launch its attack. The drug is administered intravenously.
What is MCC
Merkel cell carcinoma is an aggressive cancer and can advance rapidly. Early detection and removal are especially important. The tumors usually appear as firm, painless lesions or nodules on a sun-exposed area (frequently on the head, neck and eyelids). They are typically red, blue, purple or skin-colored and are about the size of a dime. Males over 70 years of age are most at risk of the disease.
According to the Skin Cancer Foundation, “Reduced immune functioning is a major contributor to the development of Merkel cell carcinoma, so as is always the case, it’s important to adopt a healthy lifestyle and keep your immune system strong. And since ultraviolet radiation (UV) exposure is believed to be the primary cause of the disease, it’s important to prevent UV overexposure. This is especially true if you have already had MCC, or if any close family member has had the disease or any other skin cancer.”
The trials, conducted by the National Cancer Institute (NCI), began with a phase I trial in 2012. Since then the drug has been tested in more than 1,700 patients around the world with various types of cancer, including melanoma and gastric, lung and ovarian cancers, the NCI said. The majority of the trial patients had undergone significant levels of chemotherapy. Phase II, which is still underway, is studying the effects of Avelumab in patients without prior treatment. Thus far, the results have been similar to the results with pretreated patients, the NCI said.
In the United States, Merkel cell carcinoma is diagnosed in fewer than 2,000 individuals each year, most of them elderly or with weakened immune systems. Chemotherapy can shrink Merkel cell tumors, but the cancer usually begins growing again within 6 months.
Next steps for the drug will be to seek ways to increase response rates to more patient populations, perhaps by combining Avelumab with other medications.
Immunotherapy is emerging as an important option in the treatment of many cancers. As researchers understand how cancers prevent an immune system response, they are learning how to reverse that, freeing checkpoint molecules to do their jobs and attack cancer cells.
Possible side effects from Avelumab noted by the FDA include fatigue, musculoskeletal pain, diarrhea, nausea, infusion-related reactions, rash, decreased appetite and swelling of the limbs (peripheral edema). There is some risk that the immune system will attack healthy cells or organs. The drug is approved for patients 12 years of age and older, and should not be taken by women during pregnancy.
Trials were conducted by EMD Serono, the biopharmaceutical business of Merck KGaA, Darmstadt, Germany in the US and Canada, and Pfizer Inc.