Blincyto’s launch as a breakthrough therapy
In 1Q17, Amgen’s (AMGN) Blincyto reported revenues of ~$34 million, which is equivalent to year-over-year sales growth of 26%. Blincyto’s Pivotal Phase 2 study claimed that 41.6% of Philadelphia chromosome-negative relapsed/refractory B-Cell precursor Acute Lymphoblastic Leukemia[1. or Ph-negative R/R B-precursor ALL] patients aged above 18 years could attain complete remission (or CR) or complete remission with partial hematological recovery (or CRh) after the first two therapy cycles.
Amgen’s Blincyto (blinatumomab), is a monoclonal antibody used for the treatment of patients with Ph-negative R/R B-precursor ALL. The drug is a bi-specific T-cell engager (or BiTE) which manifests its action selectively and directs the human immune system to act specifically against the tumor cells. The FDA has designated this therapy as a breakthrough. In 2016, the drug was given approval in the US for use with pediatric patients.
In the Phase 3 TOWER study, Blincyto demonstrated a twofold rise in median overall survival in adults suffering from Ph-negative R/R B-precursor ALL compared to the current standard of care (or SOC).
In collaboration with Merck (MRK), Amgen is also conducting a cancer immunotherapy Phase 1b/3 study for exploring Blincyto in combination with Keytruda for patients with diffuse large B-cell lymphoma (or DLBCL). This study is believed to help enhance the knowledge base required to expand Blincyto’s label in other cancer indications.
Amgen is the only company that has an advanced immune-oncology BiTE platform. Bi-specific T-cell engagers are fusion proteins comprising double single-chain variable fragments (or scFvs) of diverse antibodies. BiTEs crafts a link between T-cells and tumor cells where one scFvs binds to the T-cells through CD3 (cluster of differentiation 3) receptor while another scFvs binds to the tumor cell.
This leads to the manifestation of cytotoxic activity by T-cells on the tumor cells. Proteins such as perforin and granzymes, which are released in the process, carry out cell apoptosis on the tumor cells.
The success of Blincyto may support Amgen stock as well as the Health Care Select Sector SPDR ETF (XLV). Amgen makes up ~4.0% of XLV’s total portfolio holdings.
In the next article, we’ll discuss Amgen’s monoclonal antibody, Xgeva.