Blinatumomab (Blincyto) is a bispecific CD19-directed CD3 T-cell engager now approved for the treatment of adults and children with B-cell precursor acute lymphoblastic leukemia (ALL) who are in remission but still have minimal residual disease (MRD). In cases of MRD, cancer cells are present at a lower level than can be seen under a microscope, placing patients at increased risk for relapse.

Accelerated Food and Drug Administration (FDA) approval was granted when a single-arm clinical trial of 86 patients showed likely efficacy. The patients were in their first or second complete remission of ALL but had detectable MRD in at least one of 1,000 cells in their bone marrow. One treatment with blinatumomab produced undetectable MRD in 70 of the 86 patients. Over half of the patients remained alive and in remission for at least 22.3 months. Further randomized clinical trials are needed both to verify efficacy and so that blinatumomab can receive full FDA approval for this indication. Previously, blinatumomab received FDA approval to treat Philadelphia chromosome negative relapsed or refractory positive B-cell precursor ALL, as well as Philadelphia chromosome positive forms of the leukemia.

Blinatumomab carries a black box warning for cytokine release syndrome and neurologic toxicities (headache, tremor, encephalopathy, seizures, speech disorders, disturbances in consciousness, confusion and disorientation, and coordination and balance disorders), which can be severe and possibly fatal. Other warnings include the risk of serious infections (sepsis, pneumonia, bacteremia, opportunistic infections, and catheter-site infections) and pancreatitis.

Before administering blinatumomab to children weighing less than 22 kg (48.5 lbs.), the nurse should confirm that the infusion has not been prepared with benzyl alcohol, as this preservative creates a risk of serious or fatal adverse reactions (for example, gasping syndrome) in small children. Prior to the administration of blinatumomab, patients should be premedicated with prednisone or equivalent dexamethasone. Strict aseptic technique should be used. The iv tubing should be primed for infusion with the prepared solution, not with 0.9% saline. The starting volume in the bag is greater than the volume infused to account for the amount used to prime. Infuse over the prescribed number of days using an infusion pump set at a constant rate. The pump should be programmable, lockable, nonelastomeric (not a "balloon pump"), and have an alarm. If infusing blinatumomab through a multilumen line, one port should be designated solely for the drug. When administration is continued at home after the initial hospital infusion, the nurse should tell the patient and family never to adjust the infusion rate.

For complete prescribing information for blinatumomab, see http://www.accessdata.fda.gov/drugsatfda_docs/label/2018/125557s013lbl.pdf.