June 10, 2019
Today, the U.S. Food and Drug Administration granted accelerated approval to Polivy (polatuzumab vedotin-piiq), in combination with the chemotherapy bendamustine and a rituximab product (a combination known as “BR”), to treat adult patients with diffuse large B-cell lymphoma (DLBCL) that has progressed or returned after at least two prior therapies. Polivy is a novel antibody-drug conjugate, and DLBCL is the most common type of non-Hodgkin lymphoma.
“Antibody-drug conjugates are an emerging class of targeted immunotherapies for cancer. This type of therapy, unlike traditional chemotherapy, is intended to target specific cells,” said Richard Pazdur, M.D., director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “Today’s approval of Polivy provides an alternative option for patients in whom multiple treatments have not worked.”
More than 18,000 people are diagnosed with DLBCL each year in the U.S. Although it can be cured, about 30 to 40% of patients suffer relapse. This type of cancer grows quickly in the lymph nodes and may affect the bone marrow, spleen, liver or other organs. Signs and symptoms of DLBCL may include swollen lymph nodes, fever, recurring night sweats and weight loss.
Polivy is an antibody that is attached to a chemotherapy drug. Polivy binds to a specific protein (called CD79b) found only on B cells (a type of white blood cell), then releases the chemotherapy drug into those cells. Efficacy was evaluated in a study of 80 patients with relapsed or refractory DLBCL who were randomized to receive Polivy with BR or BR alone. Efficacy was based on complete response rate and duration of response (DOR), defined as the time the disease stays in remission. At the end of treatment, the complete response rate was 40% with Polivy plus BR compared to 18% with BR alone. Of the 25 patients who achieved a partial or complete response to Polivy plus BR, 16 (64%) had a DOR of at least six months and 12 (48%) had a DOR of at least 12 months.
The most common side effects of Polivy plus BR include low levels of white blood cells (neutropenia), platelets (thrombocytopenia) and red blood cells (anemia); nerve damage (peripheral neuropathy); fatigue; diarrhea; fever; decreased appetite; and pneumonia.
Health care professionals are advised to monitor patients closely for infusion-related reactions, low blood counts and fatal and/or serious infections. Health care professionals should also monitor patients for tumor lysis syndrome (a complication from many tumor cells being killed off at the same time), liver damage (hepatotoxicity) and progressive multifocal leukoencephalopathy (PML), a fatal or life-threatening infection of the brain. FDA advises health care professionals to tell females of reproductive age to use effective contraception during treatment with Polivy and for three months after the last dose. Women who are pregnant or breastfeeding should not take Polivy because it may cause harm to a developing fetus or newborn baby.
Polivy in combination with BR was granted accelerated approval, which enables the FDA to approve drugs for serious conditions to fill an unmet medical need based on an endpoint that is reasonably likely to predict a clinical benefit to patients. Further clinical trials are required to verify and describe Polivy’s clinical benefit.
The FDA granted this application Breakthrough Therapy and Priority Review designations. Polivy also received Orphan Drug designation, which provides incentives to assist and encourage the development of drugs for rare diseases. The FDA granted the approval of Polivy to Genentech.
The FDA, an agency within the U.S. Department of Health and Human Services, protects the public health by assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products for human use, and medical devices. The agency also is responsible for the safety and security of our nation’s food supply, cosmetics, dietary supplements, products that give off electronic radiation, and for regulating tobacco products.
Barbara Jacoby is an award winning blogger that has contributed her writings to multiple online publications that have touched readers worldwide.