The FDA has approved Besponsa (inotuzumab ozogamicin) for adults with relapsed or refractory B-cell precursor acute lymphoblastic leukemia (ALL), a rapidly progressing cancer affecting about 6,000 people each year. About 1 in 4 patients affected will die of the disease.
Inotuzumab ozogamicin is a targeted therapy “thought to work” by binding to B-cell ALL cancer cells that express the CD22 antigen, blocking the growth of cancerous cells. In a study of 326 patients with relapsed or refractory B-cell ALL who had received 1 or 2 prior treatments, 36% of 218 evaluated patients experienced complete remission for a median 8 months. Of the patients who received alternative chemotherapy, 17% experienced complete remission for a median 5 months.
A second drug, Vyxeos ( daunorubicin and cytarabine) liposome injection, is approved for adults with 2 types of acute myeloid leukemia (AML): newly diagnosed therapy-related AML (t-AML) or AML with myelodysplasia-related changes (AML-MRC).
An estimated 8% to 10% of patients with AML develop t-AML as a complication of chemotherapy or radiation. AML-MRC is characterized by a history of certain blood disorders and other significant mutations within cancer cells. Patients with either disease have a low life expectancy. Vyxeos is a fixed-combination of daunorubicin and cytarabine. It’s the first approved treatment specifically for these patients, says Richard Pazdur, MD, director of the FDA’s Oncology Center of Excellence.
In a study of 309 patients with newly diagnosed t-AML or AML-MRC, those in the Vyxeos group lived longer: median survival, 9.56 months vs. 5.95 months in the patients who received separate treatments with daunorubicin and cytarabine.The third drug, Idhifa (enasidenib), is approved for adults with relapsed or refractory AML who have a mutation in the IDH2 gene. Idhifa is an isocitrate dehydrogenase-2 inhibitor that blocks several enzymes that promote cell growth.
The drug was studied in a single-arm trial of 199 patients. With a minimum of 6 months of treatment, 19% of patients experienced complete remission for a median of 8.2 months; 4% experienced complete remission with partial hematologic recovery for a median 9.6 months. Of the 157 patients who required blood or platelet transfusions due to AML at the start of the study, 34% no longer did after treatment with Idhifa.
Idhifa is approved for use with a companion diagnostic, the RealTime IDH2 Assay, which is used to detect mutations in the IDH2 gene in blood or bone marrow.
Source:
FDA approves new treatment for adults with relapsed or refractory acute lymphoblastic leukemia [news release]. Silver Spring, MD: U.S. Food & Drug Administration; August 17,2017. https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm572131.htm. Accessed August 31, 2017.
FDA approves new targeted treatment for relapsed or refractory acute myeloid leukemia [news release]. Silver Spring, MD: U.S. Food & Drug Administration; August 1, 2017. https://www.fda.gov/newsevents/newsroom/pressannouncements/ucm569421.htm. Accessed August 31, 2017.
FDA approves first treatment for certain types of poor-prognosis acute myeloid leukemia [news release]. Silver Spring, MD: U.S. Food & Drug Administration; August 3, 2017. https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm569883.htm. Accessed August 31, 2017.