Amgen has filed for approval in the US for its leukaemia candidate blinatumomab, its third marketing application for a new drug in recent weeks.
Blinatumomab (AMG103) has been submitted to the FDA as a treatment for adults with Philadelphia-negative relapsed/refractory B-precursor acute lymphoblastic leukemia (ALL), a rapidly progressing cancer of the blood and bone marrow, on the strength of phase II trial results.
The antibody is the lead candidate in Amgen's bispecific T cell engager (BiTE) and was acquired by the company along with German biopharma company Micromet, snapped up for $1.16bn in 2012.
BiTE antibodies are designed to exert anticancer effects by directing the body's cell-destroying T lymphocytes to attack tumour cells, and in the case of blinatumomab targets CD19- and CD3-expressing cells.
The early application comes shortly after Amgen filed marketing applications for metastatic melanoma immunotherapy talimogene laherparepvec and PCSK9 inhibitor evolocumab for high cholesterol in both the US and Europe.
Analysts at JP Morgan have predicted blinatumomab could be a $500m-plus product at peak, behind the $4bn-$5bn predicted for evolocumab and $1bn potential for talimogene laherparepvec but still a useful addition to the company's portfolio, particularly if it proves effective in other indications such as non-Hodgkin's lymphoma (NHL).
Blinatumomab has received both orphan drug designation and breakthrough status from the FDA for the treatment of ALL, a malignancy that has "high relapse rates and … limited treatment options," according to Amgen's executive vice president of R&D Sean Harper.
In the 189-patient phase II trial, blinatumomab was given as an intravenous infusion for up to five four-week treatment cycles and achieved a complete response (CR) or CR with partial haematological recovery (CRh) in 43% of cases.
According to Amgen, over 6,000 diagnoses of ALL will be made in the US in 2014 and the disease accounts for 12% of all leukemia cases.