FDA approves Amgen’s BLINCYTO for pediatric acute lymphoblastic leukemia

This indication is approved under accelerated approval, and continued approval may be contingent upon verification of clinical benefit in subsequent trials.

The approval is based on results from the Phase 1/2 '205, an open-label, multicenter, single-arm trial, which evaluated the efficacy and safety of BLINCYTO in pediatric patients with relapsed or refractory B-cell precursor ALL.

About Study '205

Study '205 evaluated the safety and efficacy of BLINCYTO in a Phase 1/2 open-label, multicenter, single-arm study in 93 pediatric patients with relapsed or refractory B-cell precursor ALL (second or later bone marrow relapse, any marrow relapse after allogeneic hematopoietic stem cell transplantation [alloHSCT], or refractory to other treatments and had >25 percent blasts in bone marrow).

Treatment in this study has been completed and subjects are being monitored for long-term efficacy.

About BLINCYTO (blinatumomab)

BLINCYTO is a bispecific CD19-directed CD3 T cell engager (BiTE) antibody construct that binds specifically to CD19 expressed on the surface of cells of B-lineage origin and CD3 expressed on the surface of T cells.

BLINCYTO was granted breakthrough therapy, priority review and orphan drug designations by FDA, and is now approved in the U.S. for the treatment of Ph- relapsed or refractory B-cell precursor ALL.

In November 2015, BLINCYTO was granted conditional marketing authorization in the European Union for the treatment of adults with Ph- relapsed or refractory B-cell precursor ALL.

BLINCYTO U.S. Product Safety Information

Important Safety Information Regarding BLINCYTO (blinatumomab) U.S. Indication

This safety information is specific to the current U.S. approved indication.

WARNING: CYTOKINE RELEASE SYNDROME and NEUROLOGICAL TOXICITIES

Cytokine Release Syndrome (CRS), which may be life-threatening or fatal, occurred in patients receiving BLINCYTO. Interrupt or discontinue BLINCYTO as recommended.

Neurological toxicities, which may be severe, life-threatening or fatal, occurred in patients receiving BLINCYTO. Interrupt or discontinue BLINCYTO as recommended.

Contraindications

BLINCYTO® is contraindicated in patients with a known hypersensitivity to blinatumomab or to any component of the product formulation.

Warnings and Precautions

Cytokine Release Syndrome (CRS): CRS, which may be life-threatening or fatal, occurred in patients receiving BLINCYTO®. Infusion reactions have occurred and may be clinically indistinguishable from manifestations of CRS. Closely monitor patients for signs and symptoms of serious events such as pyrexia, headache, nausea, asthenia, hypotension, increased alanine aminotransferase (ALT), increased aspartate aminotransferase (AST), increased total bilirubin (TBILI), disseminated intravascular coagulation (DIC), capillary leak syndrome (CLS), and hemophagocytic lymphohistiocytosis/macrophage activation syndrome (HLH/MAS). Interrupt or discontinue BLINCYTO as outlined in the Prescribing Information (PI).

Neurological Toxicities: Approximately 64% of patients receiving BLINCYTO in clinical trials experienced neurological toxicities. The median time to onset of any neurological toxicity was 4 days. The most common (≥10%) manifestations of neurological toxicity were headache, tremor, dizziness, and altered state of consciousness.

Severe, life-threatening, or fatal neurological toxicities occurred in approximately 17% of patients, including encephalopathy, convulsions, speech disorders, disturbances in consciousness, confusion and disorientation, and coordination and balance disorders. Monitor patients for signs or symptoms and interrupt or discontinue BLINCYTO as outlined in the PI.

Infections: Approximately 25% of patients receiving BLINCYTO experienced serious infections, some of which were life-threatening or fatal. Administer prophylactic antibiotics and employ surveillance testing as appropriate during treatment. Monitor patients for signs or symptoms of infection and treat appropriately, including interruption or discontinuation of BLINCYTO as needed.

Tumor Lysis Syndrome (TLS): TLS, which may be life-threatening or fatal, has been observed. Preventive measures, including pretreatment nontoxic cytoreduction and on-treatment hydration, should be used during BLINCYTO treatment. Monitor patients for signs and symptoms of TLS and interrupt or discontinue BLINCYTO as needed to manage these events.

Neutropenia and Febrile Neutropenia, including life-threatening cases, have been observed. Monitor appropriate laboratory parameters during BLINCYTO infusion and interrupt BLINCYTO if prolonged neutropenia occurs.

Effects on Ability to Drive and Use Machines: Due to the possibility of neurological events, including seizures, patients receiving BLINCYTO are at risk for loss of consciousness, and should be advised against driving and engaging in hazardous occupations or activities such as operating heavy or potentially dangerous machinery while BLINCYTO is being administered.

Elevated Liver Enzymes: Transient elevations in liver enzymes have been associated with BLINCYTO treatment. The median time to onset of elevated liver enzymes was 3 days. In patients receiving BLINCYTO, the majority of these events were observed in the setting of CRS.

The median time to onset for these events was 15 days. Grade 3 or greater elevations in liver enzymes occurred in 6% of patients outside the setting of CRS and resulted in treatment discontinuation in less than 1% of patients.

Monitor ALT, AST, gamma-glutamyl transferase (GGT), and TBILI prior to the start of and during BLINCYTO treatment. BLINCYTO treatment should be interrupted if transaminases rise to > 5 times the upper limit of normal (ULN) or if TBILI rises to > 3 times ULN.

Pancreatitis: Fatal pancreatitis has been reported in patients receiving BLINCYTO in combination with dexamethasone in clinical trials and the post-marketing setting. Evaluate patients who develop signs and symptoms of pancreatitis and interrupt or discontinue BLINCYTO and dexamethasone as needed.

Leukoencephalopathy: Although the clinical significance is unknown, cranial magnetic resonance imaging (MRI) changes showing leukoencephalopathy have been observed in patients receiving BLINCYTO, especially in patients previously treated with cranial irradiation and anti-leukemic chemotherapy.

Preparation and administration errors have occurred with BLINCYTO treatment. Follow instructions for preparation (including admixing) and administration in the PI strictly to minimize medication errors (including underdose and overdose).

Immunization: Vaccination with live virus vaccines is not recommended for at least 2 weeks prior to the start of BLINCYTO treatment, during treatment, and until immune recovery following last cycle of BLINCYTO.

Adverse Reactions

The most common adverse reactions (≥ 20%) in the safety population studied in clinical trials were pyrexia, headache, nausea, edema, hypokalemia, anemia, febrile neutropenia, neutropenia, thrombocytopenia, and abdominal pain. The safety population included 225 patients weighing 45kg or more and 57 patients weighing less than 45kg.

In patients weighing greater than or equal to 45kg, serious adverse reactions were reported in 61% of patients. The most common serious adverse reactions (≥ 2%) included febrile neutropenia, pyrexia, sepsis, pneumonia, device-related infection, neutropenia, tremor, overdose, encephalopathy, infection, confusion and headache.

In patients weighing less than 45kg, serious adverse reactions were reported in 51% of patients. The most common serious adverse reactions (≥ 2%) included pyrexia, febrile neutropenia, cytokine release syndrome, convulsion, device-related infection, hypoxia, sepsis, and overdose

U.S. Dosage and Administration Guidelines

BLINCYTO is administered as a continuous intravenous infusion at a constant flow rate using an infusion pump which should be programmable, lockable, non-elastomeric, and have an alarm.

It is very important that the instructions for preparation (including admixing) and administration provided in the full Prescribing Information are strictly followed to minimize medication errors (including underdose and overdose).