Elranatamab

ELREXFIO is indicated for the treatment of adult patients with relapsed or refractory multiple myeloma who have received at least four prior lines of therapy, including a proteasome inhibitor, an immunomodulatory agent, and an anti-CD38 monoclonal antibody. This indication is approved under accelerated approval based on response rate and durability of response [see Clinical Studies (14) ] . Continued approval for this indication may be contingent upon verification of clinical benefit in a confirmatory trial(s). ELREXFIO is a bispecific B-cell maturation antigen (BCMA)-directed CD3 T‑cell engager indicated for the treatment of adult patients with relapsed or refractory multiple myeloma who have received at least four prior lines of therapy including a proteasome inhibitor, an immunomodulatory agent, and an anti-CD38 monoclonal antibody. This indication is approved under accelerated approval based on response rate and durability of response. Continued approval for this indication may be contingent upon verification of clinical benefit in a confirmatory trial(s). ( 1 )

ELREXFIO injection is a clear to slightly opalescent, and colorless to pale brown liquid solution available as:

• 76 mg/1.9 mL (40 mg/mL) in a single-dose vial
• 44 mg/1.1 mL (40 mg/mL) in a single-dose vial Injection :
• 76 mg/1.9 mL (40 mg/mL) in a single-dose vial. ( 3 )
• 44 mg/1.1 mL (40 mg/mL) in a single-dose vial. ( 3 )

None. None. ( 4 )

• Infections : Can cause severe, life-threatening, or fatal infections. Monitor patients for signs and symptoms of infection and treat appropriately. Do not initiate treatment in patients with active infections. ( 5.4 )
• Neutropenia : Monitor complete blood cell counts at baseline and periodically during treatment. ( 5.5 )
• Hepatotoxicity : Can cause elevated ALT, AST, and bilirubin. Monitor liver enzymes and bilirubin at baseline and during treatment as clinically indicated. ( 5.6 )
• Embryo-Fetal Toxicity : May cause fetal harm. Advise females of reproductive potential of the potential risk to the fetus and to use effective contraception. ( 5.7 , 8.1 . 8.3 )

5.1 Cytokine Release Syndrome (CRS) ELREXFIO can cause CRS, including life-threatening or fatal reactions [see Adverse Reactions (6.1) ] . In the clinical trial, CRS occurred in 58% of patients who received ELREXFIO at the recommended dosing schedule [see Dosage and Administration (2.2) ] , with Grade 1 CRS in 44% of patients, Grade 2 CRS in 14% of patients, and Grade 3 CRS in 0.5% of patients. Recurrent CRS occurred in 13% of patients. Most patients experienced CRS after the first step-up dose (43%) or the second step-up dose (19%), with 7% of patients having CRS after the first treatment dose and 1.6% of patients after a subsequent dose. The median time to onset of CRS was 2 (range: 1 to 9) days after the most recent dose, with a median duration of 2 (range: 1 to 19) days. Clinical signs and symptoms of CRS may include, but are not limited to, fever, hypoxia, chills, hypotension, tachycardia, headache, and elevated liver enzymes. Initiate therapy according to the ELREXFIO step-up dosing schedule to reduce risk of CRS and monitor patients following administration of ELREXFIO accordingly [see Dosage and Administration (2.2 , 2.5 )] . Administer pre-treatment medications prior to each dose in the step-up dosing schedule to reduce risk of CRS [see Dosage and Administration (2.3) ] . Counsel patients to seek medical attention should signs or symptoms of CRS occur. At the first sign of CRS, evaluate patients immediately for hospitalization. Manage CRS according to the recommendations and consider further management per current practice guidelines. Withhold or permanently discontinue ELREXFIO based on severity [see Dosage and Administration (2.5) ] . ELREXFIO is available only through a restricted program under a REMS [see Warnings and Precautions (5.3) ] .

5.2 Neurologic Toxicity, Including Immune Effector Cell-Associated Neurotoxicity Syndrome (ICANS) ELREXFIO can cause serious or life-threatening neurologic toxicity, including ICANS [see Adverse Reactions (6.1) ] . In the clinical trial, neurologic toxicity occurred in 59% of patients who received ELREXFIO at the recommended dosing schedule [see Dosage and Administration (2.2) ] , with Grade 3 or 4 neurologic toxicity occurring in 7% of patients. Neurologic toxicities included headache (18%), encephalopathy (15%), motor dysfunction (13%), sensory neuropathy (13%), and Guillain-Barré Syndrome (0.5%). In the clinical trial, ICANS occurred in 3.3% of patients who received ELREXFIO at the recommended dosing schedule [see Dosage and Administration (2.2) ] . Most patients had ICANS after the first step-up dose (2.7%), 1 (0.5%) patient had ICANS after the second step-up dose and 1 (0.5%) patient had ICANS after subsequent dose(s). Recurrent ICANS occurred in 1.1% of patients. The median time to onset was 3 (range: 1 to 4) days after the most recent dose, with a median duration of 2 (range: 1 to 18) days. The most frequent clinical manifestations of ICANS included a depressed level of consciousness and Grade 1 or Grade 2 Immune Effector Cell-Associated Encephalopathy (ICE) scores. The onset of ICANS can be concurrent with CRS, following resolution of CRS, or in the absence of CRS. Counsel patients to seek medical attention should signs or symptoms of neurologic toxicity occur. Monitor patients for signs and symptoms of neurologic toxicities during treatment with ELREXFIO. At the first sign of neurologic toxicity, including ICANS, evaluate and treat patients immediately based on severity. Withhold or permanently discontinue ELREXFIO based on severity per recommendations [see Dosage and Administration (2.5) ] and consider further management per current practice guidelines. Due to the potential for neurologic toxicity including ICANS, patients receiving ELREXFIO are at risk of depressed level of consciousness. Advise patients not to drive or operate heavy or potentially dangerous machinery for 48 hours after completing each of the 2 step-up doses and the first treatment dose within the ELREXFIO step-up dosing schedule and in the event of new onset of any neurological toxicity symptoms until symptoms resolve [see Dosage and Administration (2.2) ] . ELREXFIO is available only through a restricted program under a REMS [see Warnings and Precautions (5.3) ] . 5.3 ELREXFIO REMS ELREXFIO is available only through a restricted program under a REMS called the ELREXFIO REMS because of the risks of CRS and neurologic toxicity, including ICANS [see Warnings and Precautions (5.1 , 5.2 )] . Notable requirements of the ELREXFIO REMS include the following:

• Prescribers must be certified with the program by enrolling and completing training.
• Prescribers must counsel patients receiving ELREXFIO about the risk of CRS and neurologic toxicity, including ICANS, and provide patients with ELREXFIO Patient Wallet Card.
• Pharmacies and healthcare settings that dispense ELREXFIO must be certified with the ELREXFIO REMS program and must verify prescribers are certified through the ELREXFIO REMS program.
• Wholesalers and distributers must only distribute ELREXFIO to certified pharmacies or healthcare settings. Further information about the ELREXFIO REMS program is available at www.ELREXFIOREMS.com or by telephone at 1‑844‑923‑7845.

5.4 Infections ELREXFIO can cause severe, life-threatening, or fatal infections. In the clinical trial, in patients who received ELREXFIO according to the recommended dosing schedule, serious infections, including opportunistic infections, occurred in 42% of patients, with Grade 3 or 4 infections in 31%, and fatal infections in 7%. The most common serious infections reported (≥5%) were pneumonia and sepsis [see Adverse Reactions (6.1) ] . Do not initiate treatment with ELREXFIO in patients with active infections. Monitor patients for signs and symptoms of infection prior to and during treatment with ELREXFIO and treat appropriately. Withhold or permanently discontinue ELREXFIO based on severity [see Dosage and Administration (2.5) ] . Administer prophylactic antimicrobial and anti-viral medications according to current practice guidelines. Consider treatment with subcutaneous or intravenous immunoglobulin (IVIG) as appropriate.

5.5 Neutropenia ELREXFIO can cause neutropenia and febrile neutropenia. In patients who received ELREXFIO at the recommended dose in the clinical trial, decreased neutrophils occurred in 62% of patients, with Grade 3 or 4 decreased neutrophils in 51%. Febrile neutropenia occurred in 2.2% of patients [see Adverse Reactions (6.1) ] . Monitor complete blood cell counts at baseline and periodically during treatment. Provide supportive care according to current practice guidelines. Monitor patients with neutropenia for signs of infection. Withhold ELREXFIO based on severity [see Dosage and Administration (2.5) ] .

5.6 Hepatotoxicity ELREXFIO can cause hepatotoxicity. In the clinical trial, elevated ALT occurred in 36% of patients, with Grade 3 or 4 ALT elevation occurring in 3.8%; elevated AST occurred in 40% of patients, with Grade 3 or 4 AST elevation occurring in 6%. Grade 3 or 4 total bilirubin elevations occurred in 0.5% of patients [see Adverse Reactions (6.1) ]. Liver enzyme elevation can occur with or without concurrent CRS. Monitor liver enzymes and bilirubin at baseline and during treatment as clinically indicated. […]

The following adverse reactions are discussed elsewhere in labeling:

• Cytokine Release Syndrome [see Warnings and Precautions (5.1) ] .
• Neurologic Toxicity, Including ICANS [see Warnings and Precautions (5.2) ] .
• Infections [see Warnings and Precautions (5.4) ] .
• Neutropenia [see Warnings and Precautions (5.5) ] .
• Hepatotoxicity [see Warnings and Precautions (5.6) ] . Most common adverse reactions (incidence ≥20%) are CRS, fatigue, injection site reaction, diarrhea, upper respiratory tract infection, musculoskeletal pain, pneumonia, decreased appetite, rash, cough, nausea, and pyrexia. The most common Grade 3 to 4 laboratory abnormalities (≥30%) are decreased lymphocytes, decreased neutrophils, decreased hemoglobin, decreased white blood cells, and decreased platelets. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Pfizer Inc. at 1-800-438-1985 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Relapsed/Refractory Multiple Myeloma MagnetisMM-3 The safety of ELREXFIO was evaluated in MagnetisMM-3 [see Clinical Studies (14) ]. The safety population described (n = 183) includes patients who received the recommended dosage regimen of 12 mg subcutaneously on Day 1, 32 mg on Day 4, and 76 mg once weekly starting on Day 8. Among patients who received ELREXFIO, 42% were exposed for 6 months or longer and 9% were exposed for one year or longer. The median age of patients who received ELREXFIO was 68 years (range: 36 to 88 years); 48% were female; 61% were White, 10% were Hispanic/Latino, 9% were Asian, and 6% were Black or African American. Serious adverse reactions occurred in 68% of patients who received ELREXFIO at the recommended dosing schedule. Serious adverse reactions in >2% of patients included pneumonia (25%), sepsis (13%), CRS (13%), upper respiratory tract infection (4.4%), acute kidney injury (3.8%), urinary tract infection (3.3%), COVID-19 (3.3%), encephalopathy (3.3%), pyrexia (2.2%), and febrile neutropenia (2.2%). Fatal adverse reactions occurred in 10% of patients including pneumonia (3.3%), sepsis (2.7%), acute respiratory distress syndrome (0.5%), cardio-respiratory arrest (0.5%), cardiogenic shock (0.5%), cardiopulmonary failure (0.5%), COVID-19 (0.5%), failure to thrive (0.5%), and pulmonary embolism (0.5%). Permanent discontinuations of ELREXFIO due to an adverse reaction occurred in 17% of patients. Adverse reactions which resulted in permanent discontinuation of ELREXFIO in >2% of patients included septic shock (2.2%). Dosage interruptions of ELREXFIO due to an adverse reaction occurred in 73% of patients. Adverse reactions which resulted in dose interruptions of ELREXFIO in >5% of patients included neutropenia, pneumonia, COVID-19, upper respiratory tract infection, thrombocytopenia, and anemia. The most common adverse reactions (≥20%) were CRS, fatigue, injection site reaction, diarrhea, upper respiratory tract infection, musculoskeletal pain, pneumonia, decreased appetite, rash, cough, nausea, and pyrexia. The most common Grade 3 to 4 laboratory abnormalities (≥30%) were decreased lymphocytes, decreased neutrophils, decreased hemoglobin, decreased white blood cells, and decreased platelets. Table 8 summarizes adverse reactions in MagnetisMM-3. Table 8. Adverse Reactions (≥10%) in Patients with Relapsed or Refractory Multiple Myeloma Who Received ELREXFIO in MagnetisMM-3 Adverse reactions were graded based on CTCAE Version 5.0, with the exception of CRS, which was graded based on the ASTCT 2019 criteria. System Organ Class Preferred Term ELREXFIO N = 183 All Grades (%) Grade 3 or 4 (%) Immune system disorders Cytokine release syndrome 58

0.5 Only grade 3 adverse reactions occurred. Hypogammaglobulinemia Includes other related terms. 13

2.2 General disorders and site administration conditions Fatigue 43 6 Injection site reaction 37 0 Pyrexia 21

2.7 Edema 18

1.1 Gastrointestinal disorders Diarrhea 36

1.1 Nausea 21 0 Constipation 14 0 Vomiting 14 0 Infections Upper respiratory tract infection 36

4.9 Pneumonia Pneumonia includes COVID-19 pneumonia, lower respiratory tract infection, lower respiratory tract infection viral, pneumocystis jirovecii pneumonia, pneumonia, pneumonia adenoviral, pneumonia bacterial, pneumonia cytomegaloviral, pneumonia fungal, pneumonia influenzal, pneumonia pseudomonal, pneumonia viral. 32 19 Sepsis Sepsis includes bacteremia, device related bacteremia, device related sepsis, escherichia bacteremia, escherichia sepsis, klebsiella sepsis, pseudomonal sepsis, sepsis, septic shock, staphylococcal bacteremia, staphylococcal sepsis, streptococcal sepsis, urosepsis. 15 11 Urinary tract infection 12

4.4 Musculoskeletal and connective tissue disorders Musculoskeletal pain 34

2.7 Metabolism and nutrition disorders Decreased appetite 26

1.1 Skin and Subcutaneous Tissue disorders Rash Rash incudes erythema, palmar-plantar erythrodysesthesia syndrome, rash, rash erythematous, rash macular, rash maculo-papular, rash pustular, symmetrical drug-related intertriginous and flexural exanthema. 26 0 Dry skin 14 0 Skin exfoliation 10 0 Respiratory, thoracic and mediastinal disorders Cough 24 0 Dyspnea 15

3.3 Nervous system disorders Headache 18 0 Encephalopathy Encephalopathy includes agitation, altered state of consciousness, cognitive disorder, confusional state, delirium, depressed level of consciousness, disorientation, hallucination, lethargy, memory impairment, metabolic encephalopathy, somnolence, toxic encephalopathy. 14

2.2 Sensory neuropathy Sensory neuropathy includes burning sensation, dysesthesia, hypoesthesia, neuropathy peripheral, paresthesia, parosmia, peripheral sensorimotor neuropathy, peripheral sensory neuropathy, polyneuropathy, sensory loss. 13

0.5 Motor dysfunction Motor dysfunction includes ataxia, balance disorder, gait disturbance, motor dysfunction, muscle contracture, muscle spasms, muscular weakness, peripheral motor neuropathy, peroneal nerve palsy, tremor. 14

1.1 Cardiac disorders Cardiac arrhythmia 16

1.6 Vascular disorders Hemorrhage 13

1.6 Psychiatric disorders Insomnia 13 0 Injury, poisoning and procedural complications Fall 10

0.5 Clinically relevant adverse reactions in <10% of patients who received ELREXFIO included ICANS, febrile neutropenia, Guillain-Barré syndrome, abdominal pain, acute kidney injury, COVID-19, cardiac failure, congestion, thrombosis, cytomegalovirus infection, and progressive multifocal leukoencephalopathy. Table 9 summarizes laboratory abnormalities in MagnetisMM-3. Table 9. Select Laboratory Abnormalities (≥30%) That Worsened from Baseline in Patients with Relapsed or Refractory Multiple Myeloma Who Received ELREXFIO in MagnetisMM-3 Laboratory tests were graded according to NCI-CTCAE Version 5.0. Laboratory Abnormality ELREXFIO The denominator used to calculate the rate varied from 181 to 183 based on the number of patients with a baseline value and at least one post-treatment value. All Grades (%) Grade 3 or 4 (%) Hematology Lymphocyte count decreased 91 84 White blood cell decreased 69 40 Hemoglobin decreased 68 43 Neutrophil count decreased 62 51 Platelet count decreased 61 32 Chemistry Albumin decreased 55 6 AST increase 40 6 Creatinine increased 38

3.3 Potassium decreased 36 8 ALT increase 36

3.8 Alkaline phosphatase increased 34

1.1 Creatinine clearance decreased 32 10

For certain CYP substrates, minimal changes in the concentration may lead to serious adverse reactions. Monitor for toxicity or drug concentrations of such CYP substrates when co-administered with ELREXFIO. ELREXFIO causes release of cytokines [see Clinical Pharmacology (12.2) ] that may suppress activity of cytochrome P450 (CYP) enzymes, resulting in increased exposure of CYP substrates. Increased exposure of CYP substrates is more likely to occur after the first dose of ELREXFIO Day 1 and up to 14 days after the 32 mg dose on Day 4 and during and after CRS [see Warnings and Precautions (5.1) ].

Lactation : Advise not to breastfeed. ( 8.2 )

8.1 Pregnancy Risk Summary Based on the mechanism of action, ELREXFIO may cause fetal harm when administered to a pregnant woman [see Clinical Pharmacology (12.1) ] . There are no available data on the use of ELREXFIO in pregnant women to evaluate for a drug associated risk. No animal reproductive or developmental toxicity studies have been conducted with ELREXFIO. Elranatamab-bcmm causes T-cell activation and cytokine release; immune activation may compromise pregnancy maintenance. In addition, based on the finding of B-cell depletion in non-pregnant animals, elranatamab-bcmm can cause B-cell lymphocytopenia in infants exposed to elranatamab-bcmm in-utero. Human immunoglobulin (IgG) is known to cross the placenta after the first trimester of pregnancy; therefore, elranatamab-bcmm has the potential to be transmitted from the mother to the developing fetus. Advise women of the potential risk to the fetus. ELREXFIO is associated with hypogammaglobulinemia, therefore, assessment of immunoglobulin levels in newborns of mothers treated with ELREXFIO should be considered. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.

8.2 Lactation Risk Summary There are no data on the presence of elranatamab-bcmm in human milk, the effects on the breastfed child, or the effects on milk production. Maternal IgG is known to be present in human milk. Because of the potential for serious adverse reactions in a breastfed child, advise women not to breastfeed during treatment with ELREXFIO and for 4 months after the last dose.

8.3 Females and Males of Reproductive Potential ELREXFIO may cause fetal harm when administered to a pregnant woman [see Use in Specific Populations (8.1) ] . Pregnancy Testing Verify the pregnancy status of females of reproductive potential prior to initiating treatment with ELREXFIO. Contraception Females Advise females of reproductive potential to use effective contraception during treatment and for 4 months after the last dose of ELREXFIO.

8.4 Pediatric Use The safety and effectiveness of ELREXFIO in pediatric patients have not been established.

8.5 Geriatric Use Of the 183 patients with relapsed or refractory multiple myeloma treated with ELREXFIO in MagnetisMM-3 at the recommended dosage, 62% were 65 years of age or older, and 19% were 75 years of age or older. No overall differences in safety or effectiveness were observed in patients 65-74 years of age compared to younger patients. Clinical studies did not include sufficient numbers of patients 75 years of age or older to determine whether they respond differently from younger patients.

Elranatamab-bcmm is a bispecific B-cell maturation antigen (BCMA)-directed T-cell engaging antibody that binds BCMA on plasma cells, plasmablasts, and multiple myeloma cells and CD3 on T-cells leading to cytolysis of the BCMA-expressing cells. Elranatamab-bcmm activated T-cells, caused proinflammatory cytokine release, and resulted in multiple myeloma cell lysis.