Amgen Inc.'s Blincyto received the U.S. Food and Drug Administration's accelerated approval to expand its usage to certain patients with an aggressive form of blood cancer.
The expanded approval is indicated to treat adults and children with B-cell precursor acute lymphoblastic leukemia, or ALL, who are in remission but still have minimal residual disease — the presence of cancer cells below a level observable under a microscope.
B-cell precursor ALL is a rapidly progressing type of cancer in which the bone marrow makes too many B-cell lymphocytes, an immature type of white blood cell.
For patients achieving remission after initial treatment for this type of ALL, the presence of minimal residual disease, or MRD, means they are at greater risk of relapsing.
About 5,960 people in the U.S. will be diagnosed with ALL in 2018, out of which about 1,470 will die from the disease, the FDA stated, citing estimates from the National Cancer Institute.
Amgen reported Blincyto sales of $175 million for 2017, up 52% from $115 million in 2016.
Blincyto, or blinatumomab, was first approved under accelerated approval in December 2014 by the FDA to treat Philadelphia chromosome-negative positive B-cell precursor ALL that has spread or is resistant to treatment. This usage was granted full approval and expanded to include patients with Philadelphia chromosome-positive ALL in July 2017.
The drug's efficacy in MRD-positive ALL was demonstrated in a study of 86 patients in first or second complete remission who had detectable MRD in at least 1 out of 1,000 cells in their bone marrow. Results of the trial showed that a total of 70 patients achieved undetectable MRD and more than half of the patients remained alive and in remission for at least 22.3 months.
Blincyto's latest usage approval requires further study in randomized controlled trials to verify that acquiring undetectable MRD with the medicine helps in better survival or disease-free survival in patients with ALL, according to the FDA.
The FDA has already granted this application priority review and an orphan drug designation.