Amgen Announces BLINCYTO® (blinatumomab) Five-Year Overall Survival Data At EHA 2019

Amgen announced the five-year overall survival (OS) analysis from the single-arm, Phase 2 BLAST study that evaluated BLINCYTO^® (blinatumomab) in patients with minimal residual disease (MRD)-positive acute lymphoblastic leukemia (ALL). The study found that with a median follow-up of 59.8 months, the median OS for BLINCYTO-treated patients was 36.5 months (95 percent CI: 22 months - not estimable [NE]). More than half of patients who achieved a complete MRD response following the first cycle of BLINCYTO treatment were alive at five years. These results from the largest prospective trial ever conducted in MRD-positive.

"As the only CD19-targeted immuno-oncology therapy with five-year survival data, BLINCYTO continues to demonstrate compelling results for ALL patients," said David M. Reese, M.D., executive vice president of Research and Development at Amgen. "We are proud of the science behind our BiTE^® technology. These data in an MRD-positive ALL patient population give us increased confidence in the clinical benefit of BLINCYTO, especially when these patients are treated earlier."

The Phase 2 open-label BLAST study enrolled 116 patients with MRD-positive Philadelphia chromosome-negative (Ph-) B-cell precursor ALL in first or subsequent complete hematologic remission after at least three intensive chemotherapy blocks of treatment. Of the 116 enrolled patients, OS was evaluated for 110 patients with less than five percent leukemic blasts, including 74 patients who received hematopoietic stem cell transplantation (HSCT) in continuous complete remission (CCR) after BLINCYTO treatment.

Results presented at EHA showed that in 84 patients who achieved a complete MRD response (had no measurable MRD), median OS was not reached (95 percent CI: 29.5 months - NE) compared to 14.4 months for those who had measurable MRD (n=23; 95 percent CI: 3.8 - 32.3 months). Among patients with MRD in first complete remission (CR1), median OS was not reached for those who achieved a complete MRD response (95 percent CI: 29.5 months - NE) versus 10.6 months (95 percent CI: 2.7 - 39.7 months) for those who did not achieve complete MRD response (n=13; p=0.008).

"The presence of MRD is a strong predictor of relapse in patients with B-cell precursor ALL," said Nicola Gökbuget, M.D., principal investigator for the BLAST study and head of the German Multicenter Study Group for Adult ALL in Frankfurt, Germany. "Results from the final follow-up of the BLAST trial at five years demonstrate that early achievement of complete molecular remission with BLINCYTO is associated with prolonged survival."

Safety results among MRD-positive patients were consistent with the known safety profile of BLINCYTO.  

MRD refers to the presence of cancer cells that remain detectable, despite a patient having achieved complete remission by conventional assessment.¹ The presence of MRD is broadly considered the most important independent prognostic factor in ALL.^2-8 MRD is only measurable through the use of highly sensitive testing methods that detect cancer cells in the bone marrow with a sensitivity of at least one cancer cell in 10,000 cells – versus about one in 20 with a conventional microscope-based evaluation.^1,9,10

BLINCYTO, a bispecific CD19-directed CD3 T ce ll BiTE^® (bispecific T cell engager) molecule, is the first approved molecule from Amgen's BiTE immuno-oncology platform, and the first and only therapy to receive regulatory approval globally for the treatment of MRD. 

About the BLAST Study 
The BLAST study is the largest prospective trial in patients with MRD-positive ALL. It is an open-label, multicenter, single-arm, Phase 2 study that evaluated the efficacy, safety and tolerability of BLINCYTO in adult patients with MRD-positive B-cell precursor ALL in complete hematologic remission after three or more cycles of intensive chemotherapy. Patients received continuous intravenous infusion of BLINCYTO 15 μg/m²/d for four weeks, followed by two weeks off. Patients received up to four cycles of treatment and could undergo HSCT at any time after the first cycle, if eligible. Efficacy was based on achievement of undetectable MRD within one cycle of BLINCYTO treatment and hematological relapse-free survival (RFS). Results from the primary analysis BLAST study were presented at the 57^th American Society of Hematology (ASH) Annual Meeting & Exposition in 2015 and published in Blood in 2018. Additional secondary endpoints included incidence and severity of adverse events, OS, time to hematological remission and duration of complete MRD response. Survival follow-up visits for assessment of hematological RFS and OS took place every six months until completion of a five-year period after treatment start with BLINCYTO. Three-year OS data results from the BLAST study were also featured in an oral presentation during the 60^th ASH Annual Meeting & Exposition on Dec. 3, 2018.

About ALL and MRD 
ALL is a rapidly progressing cancer of the blood and bone marrow that occurs in both adults and children.^11,12 Poor outcomes have been observed in patients who achieve first or second complete hematologic remission but are persistently MRD-positive, which currently remains detectable at the molecular level after treatment.^1,8 For more information about MRD, please visit AmgenOncology.com.   

About BiTE Technology 
BiTE (Bispecific T cell engager) technology is a targeted immuno-oncology platform that is designed to engage patients' own T cells to any tumor-specific antigen, activating the cytotoxic potential of T cells with the goal of eliminating detectable cancer. The BiTE immuno-oncology platform has the potential to treat different tumor types through tumor-specific antigens. The BiTE platform has the goal of off-the-shelf solutions, which have the potential to make innovative T cell treatment available to all providers when their patients need it. Amgen is advancing more than a dozen BiTE molecules across a broad range of solid and hematologic malignancies, further investigating BiTE technology with the goal of enhancing patient experience and therapeutic potential.

About BLINCYTO^® (blinatumomab) 
BLINCYTO is a bispecific CD19-directed CD3 T cell BiTE (bispecific T cell engager), immunotherapy that binds to CD19 expressed on the surface of cells of B-lineage origin and CD3 expressed on the surface of effector T cells. BLINCYTO was granted breakthrough therapy and priority review designations by the U.S. Food and Drug Administration in 2014, and carries full approval in the U.S. for the treatment of relapsed or refractory B-cell precursor ALL in adults and children. In the U.S., BLINCYTO is also approved for the treatment of adults and children with B-cell precursor ALL in first or second complete remission with MRD greater than or equal to 0.1 percent. This indication is approved under accelerated approval based on MRD response rate and hematological RFS. Continued approval for this indication may be contingent upon verification and description of clinical benefit in the confirmatory trials. In the European Union (EU), BLINCYTO is indicated for the treatment of adults with Philadelphia chromosome-negative (Ph-) relapsed or refractory B-precursor ALL and for the treatment of Ph- CD19-positive B-cell precursor ALL in first or second complete remission with MRD greater than or equal to 0.1 percent.BLINCYTO is now approved in 57 countries, including all member countries in the EU, Canada, Japan and Australia.

Important EU BLINCYTO^® (blinatumomab) Safety Information

This product is subject to additional monitoring in the EU. All suspected adverse reactions should be reported in accordance with the national reporting system.
The adverse reactions described in this section were identified in clinical studies of patients with B-precursor ALL (N = 843). The most serious adverse reactions that may occur during blinatumomab treatment include: infections (24.8%), neurologic events (13.8%), neutropenia/febrile neutropenia (10.1%), cytokine release syndrome (3.3%), and tumour lysis syndrome (0.7%). The most common adverse reactions were: pyrexia (69.2%), infusion-related reactions (43.4%), infections – pathogen unspecified (42.1%), headache (32.9%), anaemia (22.8%), thrombocytopenia (20.9%), febrile neutropenia (20.2%), oedema (20.0%), neutropenia (19.7%), rash (16.7%), increased liver hepatic enzymes (16.1%), bacterial infectious disorders (15.4%), tremor (15.2%), cough (15.1%), leukopenia (13.4%), back pain (13.3%), chills (13.0%), hypotension (12.8%), viral infectious disorders (12.7%), decreased immunoglobulins (12.5%), cytokine release syndrome (11.6%), tachycardia (11.3%), insomnia (10.7%), fungal infectious disorders (10.6%) and pain in extremity (10.2%).

Important Safety Information Regarding BLINCYTO^® (blinatumomab) U.S. 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^®. The median time to onset of CRS is 2 days after the start of infusion. Closely monitor patients for signs and symptoms of serious adverse events such as fever, headache, nausea, asthenia, hypotension, increased alanine aminotransferase (ALT), increased aspartate aminotransferase (AST), increased total bilirubin (TBILI), and disseminated intravascular coagulation (DIC). The manifestations of CRS after treatment with BLINCYTO overlap with those of infusion reactions, capillary leak syndrome (CLS), and hemophagocytic histiocytosis/macrophage activation syndrome (MAS). In clinical trials of BLINCYTO, CRS was reported in 15% of patients with relapsed or refractory ALL and in 7% of patients with MRD-positive ALL. Interrupt or discontinue BLINCYTO^® for evidence of CRS, as outlined in the PI.
• Neurological Toxicities: Approximately 65% of patients receiving BLINCYTO^® in clinical trials experienced neurological toxicities. The median time to the first event was within the first 2 weeks of BLINCYTO^® treatment, and the majority of events resolved. The most common (≥ 10%) manifestations of neurological toxicity were headache and tremor. Severe, life‐threatening, or fatal neurological toxicities occurred in approximately 13% of patients, including encephalopathy, convulsions, speech disorders, disturbances in consciousness, confusion and disorientation, and coordination and balance disorders. Manifestations of neurological toxicity included cranial nerve disorders. Monitor patients for signs or symptoms of neurological toxicity and interrupt or discontinue BLINCYTO^® as outlined in the PI.
• Infections: Approximately 25% of patients receiving BLINCYTO^® in clinical trials experienced serious infections such as sepsis, pneumonia, bacteremia, opportunistic infections, and catheter-site 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), 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 (including, but not limited to, white blood cell count and absolute neutrophil count) 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 with a median time to onset of 3 days. In patients receiving BLINCYTO^®, although the majority of these events were observed in the setting of CRS, some cases of elevated liver enzymes were observed outside the setting of CRS, with a median time to onset of 19 days. Grade 3 or greater elevations in liver enzymes occurred in approximately 7% 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 antileukemic 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^®.
• Risk of Serious Adverse Reactions in Pediatric Patients due to Benzyl Alcohol Preservative: Serious and fatal adverse reactions including "gasping syndrome," which is characterized by central nervous system depression, metabolic acidosis, and gasping respirations, can occur in neonates and infants treated with benzyl alcohol-preserved drugs including BLINCYTO^® (with preservative). When prescribing BLINCYTO^® (with preservative) for pediatric patients, consider the combined daily metabolic load of benzyl alcohol from all sources including BLINCYTO^® (with preservative) and other drugs containing benzyl alcohol. The minimum amount of benzyl alcohol at which serious adverse reactions may occur is not known. Due to the addition of bacteriostatic saline, 7-day bags of BLINCYTO^®solution for infusion with preservative contain benzyl alcohol and are not recommended for use in any patients weighing < 22 kg.

Adverse Reactions

• The most common adverse reactions (≥ 20%) in clinical trial experience of patients with MRD-positive B-cell precursor ALL (BLAST Study) treated with BLINCYTO® were pyrexia, infusion related reactions, headache, infections (pathogen unspecified), tremor, and chills. Serious adverse reactions were reported in 61% of patients. The most common serious adverse reactions (≥ 2%) included pyrexia, tremor, encephalopathy, aphasia, lymphopenia, neutropenia, overdose, device related infection, seizure, and staphylococcal infection.
• The most common adverse reactions (≥ 20%) in clinical trial experience of patients with Philadelphia chromosome-negative relapsed or refractory B-cell precursor ALL (TOWER Study) treated with BLINCYTO^® were infections (bacterial and pathogen unspecified), pyrexia, headache, infusion-related reactions, anemia, febrile neutropenia, thrombocytopenia, and neutropenia. Serious adverse reactions were reported in 62% of patients. The most common serious adverse reactions (≥ 2%) included febrile neutropenia, pyrexia, sepsis, pneumonia, overdose, septic shock, CRS, bacterial sepsis, device related infection, and bacteremia.
• Adverse reactions that were observed more frequently (≥ 10%) in the pediatric population compared to the adult population were pyrexia (80% vs. 61%), hypertension (26% vs. 8%), anemia (41% vs. 24%), infusion-related reaction (49% vs. 34%), thrombocytopenia (34% vs. 21%), leukopenia (24% vs. 11%), and weight increase (17% vs. 6%).
• In pediatric patients less than 2 years old (infants), the incidence of neurologic toxicities was not significantly different than the other age groups, but its manifestations were different; the only event terms reported were agitation, headache, insomnia, somnolence, and irritability. Infants also had an increased incidence of hypokalemia (50%) compared to other pediatric age cohorts (15-20%) or adults (17%).

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).

Please see full Prescribing Information, including Boxed WARNINGS and Medication Guide, for BLINCYTO^®.

About Amgen Oncology 
Amgen Oncology is searching for and finding answers to incredibly complex questions that will advance care and improve lives for cancer patients and their families. Our research drives us to understand the disease in the context of the patient's life – not just their cancer journey – so they can take control of their lives.

For the last four decades, we have been dedicated to discovering the firsts that matter in oncology and to finding ways to reduce the burden of cancer. Building on our heritage, Amgen continues to advance the largest pipeline in the Company's history, moving with great speed to advance those innovations for the patients who need them.

At Amgen, we are driven by our commitment to transform the lives of cancer patients and keep them at the center of everything we do.   

For more information, visit www.amgen.com 

CONTACT: Amgen, Thousand Oaks 
Kristen Davis, 805-447-3008 (Media) 
Trish Hawkins, 805-447-5631 (Media) 
Arvind Sood, 805-447-1060 (Investors)

References:

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3. Gokbuget N, et al., Blinatumomab for minimal residual disease in adults with B-precursor acute lymphoblastic leukemia. Blood. 2018;131(14):1522-1531.
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6. Bruggemann M,  et al. Clinical significance of minimal residual disease quantification in adult patients with standard-risk acute lymphoblastic leukemia. Blood. 2006;107(3):1116-23.
7. van Dongen JJ, et al. Minimal residual disease diagnostics in acute lymphoblastic leukemia: need for sensitive, fast, and standardized technologies. Blood. 2015;125(26):3996-4009.
8. Bassan R, Spinelli O. Minimal residual disease monitoring in adult ALL to determine therapy. Curr Hematol Malig Rep. 2015;10(2):86-95.
9. Gökbuget N, et al. Adult patients with acute lymphoblastic leukemia and molecular failure display a poor prognosis and are candidates for stem cell transplantation and targeted therapies. Blood. 2012;120:1868-1876.
10. Brüggemann M, et al. Has MRD monitoring superseded other prognostic factors in adult ALL? Blood. 2012;120:4470-4481.
11. Cancer Research UK. About acute lymphoblastic leukaemia (ALL). https://www.cancerresearchuk.org/about-cancer/acute-lymphoblastic-leukaemia-all/about. Accessed June 10, 2019. 
12. Mayo Clinic. Acute lymphocytic leukemia. https://www.mayoclinic.org/diseases-conditions/acute-lymphocytic-leukemia/basics/definition/con-20042915. Accessed June 10, 2019.