乌鸦传媒

WASHINGTON -- The FDA granted Monday for the first-ever chemoimmunotherapy regimen for relapsed/refractory diffuse large B-cell lymphoma (DLBCL).

The regimen comprises the antibody-drug conjugate (ADC) polatuzumab vedotin-piiq (Polivy), bendamustine, and a rituximab product (Rituxan or biosimilar). The approved indication is for adults with DLBCL that progressed or relapsed after at least two prior therapies.

"Antibody-drug conjugates are an emerging class of targeted immunotherapies for cancer," Richard Pazdur, MD, of the FDA Center for Drug Evaluation and Research, said in a statement. "This type of therapy, unlike chemotherapy, is intended to target specific cells."

A recent review showed increasing use of ADCs, including polatuzumab vedotin, to treat non-Hodgkin lymphoma, of which DLBCL is the most common subtype. Polatuzumab vedotin targets the B-cell antigen CD79b and releases a chemotherapeutic agent directly into the cells.

Primary support for the conditional approval came from a randomized clinical trial involving 80 patients with relapsed or refractory DLBCL. The patients received bendamustine and rituximab with or without polatuzumab vedotin. The primary results showed a 40% complete response rate with the ADC-containing regimen and 18% without it. Two-thirds of responses attained with the ADC regimen persisted for at least 6 months and almost half continued for a year or longer.

The most common side effects among patients treated with the ADC-containing regimen were neutropenia, thrombocytopenia, anemia, peripheral neuropathy, fatigue, decreased appetite, and pneumonia. Other potential adverse effects include infusion-related reactions and serious infections. The FDA announcement included an advisory about monitoring patients treated with the regimen for signs of tumor lysis syndrome, hepatotoxicity, and progressive multifocal encephalopathy.

The FDA granted the accelerated approval of polatuzumab vedotin to Genentech. The approval will become final if additional required clinical trials corroborate the results that led to Monday's conditional approval.