The FDA has approved venetoclax (Venclexta, AbbVie/Genentech) for the treatment of patients with chronic lymphocytic leukemia (CLL) who have a chromosomal abnormality called 17p deletion and who have been treated with at least one prior therapy. Venetoclax is the first FDA-approved treatment that targets the B-cell lymphoma 2 (BCL-2) protein, which supports cancer cell growth and is overexpressed in many patients with CLL.
According to the National Cancer Institute, CLL is one of the most common types of leukemia in adults, with approximately 15,000 new cases diagnosed each year. Patients with CLL who have a 17p deletion lack a portion of the chromosome that suppresses cancer growth. This chromosomal abnormality occurs in approximately 10% of patients with untreated CLL and in approximately 20% of patients with relapsed disease.
The efficacy of venetoclax was evaluated in a single-arm clinical trial involving 106 patients with CLL who had a 17p deletion and who had received at least one prior therapy. The subjects received oral venetoclax every day for five weeks, beginning with 20 mg and increasing to 400 mg. The study results showed that 80% of the subjects experienced complete or partial remission of their cancer.
Venetoclax is indicated for daily use after detection of 17p deletion has been confirmed through the use of an FDA-approved companion diagnostic, the Vysis CLL FISH probe kit (Abbott Molecular).
The most common adverse events associated with venetoclax include neutropenia, diarrhea, nausea, anemia, upper respiratory tract infection, thrombocytopenia, and fatigue. Serious adverse events include pneumonia, neutropenia with fever, fever, autoimmune hemolytic anemia, anemia, and metabolic abnormalities known as tumor lysis syndrome. Live attenuated vaccines should not be given to patients receiving venetoclax.
Source: FDA; April 11, 2016.