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.

The pooled safety population described in the WARNINGS AND PRECAUTIONS reflects exposure to intravenous IMDELLTRA, as a single agent, at the recommended dosage of IMDELLTRA 1 mg on Cycle 1 Day 1 followed by 10 mg on Days 8 and 15, and then every 2 weeks until disease progression or intolerable toxicity in 473 patients with small cell lung cancer enrolled in three clinical trials: DeLLphi-300, DeLLphi-301 and DeLLphi-304. Among 473 patients who received IMDELLTRA, 40% were exposed for 6 months or longer and 19% were exposed for greater than one year. The most common (≥ 20%) adverse reactions were CRS (57%), fatigue (48%), decreased appetite (38%), dysgeusia (34%), pyrexia (33%), constipation (31%), musculoskeletal pain (31%), and nausea (25%). The most common (≥ 5%) Grade 3 or 4 laboratory abnormalities were decreased lymphocytes (43%), decreased sodium (12%), decreased total neutrophils (9%), and increased uric acid (6%).

The safety of IMDELLTRA was evaluated in 252 patients in DeLLphi-304, a multicenter, randomized, open label trial in patients with extensive stage small cell lung cancer (ES- SCLC) with disease progression following treatment with platinum-based chemotherapy with or without an anti-PD-(L)1 antibody

Among patients who received IMDELLTRA, 41% were exposed for 6 months or longer and 18% were exposed for greater than one year.

The demographic characteristics of patients who received IMDELLTRA were: median age 64 years (range: 20 to 86); 71% male; 60% White, 38 % Asian, 0.8% Black or African American; and 4.8% were of Hispanic or Latino ethnicity.

Serious adverse reactions occurred in 52% of patients who received IMDELLTRA. Serious adverse reactions in >3% of patients included CRS (17%), pyrexia (6%), pneumonia (5%) and ICANS (3.6%). Fatal adverse reactions occurred in 8% of patients who received IMDELLTRA, including one fatal adverse reaction of ICANS (0.4%). Fatal adverse reactions occurring in more than one patient included pneumonia (1.6%), cardio-respiratory arrest (1.6%), and sepsis (0.8%).

Permanent discontinuation of IMDELLTRA due to an adverse reaction occurred in 6% of patients. Adverse reactions which resulted in permanent discontinuation of IMDELLTRA in > 1% of patients included pneumonia (1.2%).

Dosage interruptions of IMDELLTRA due to an adverse reaction occurred in 38% of patients. Adverse reactions which required dosage interruption in ≥ 2% of patients included neutropenia (5%), fatigue (4.4%), pneumonia (4%), decreased appetite (2.8%), COVID-19 (2%).

Table 13 summarizes adverse reactions observed in DeLLphi-304.

Clinically relevant adverse reactions occurring in < 15% of patients who received IMDELLTRA were immune effector cell-associated neurotoxicity syndrome, neurotoxicity, tremor, seizure, ataxia, confusional state, delirium, dyspnea, encephalopathy and weight decreased.

Table 14 summarizes laboratory abnormalities in DeLLphi-304.

The safety of IMDELLTRA, as a single agent, at the recommended dosage was evaluated in patients with extensive stage small cell lung cancer enrolled in DeLLphi-300 and DeLLphi-301

The demographic characteristics of patients who received IMDELLTRA were: median age 66 years (range: 35 to 82); 65% male; 70% White, 26% Asian, 2.1% Black or African American; and 2.1% Hispanic or Latino.

Serious adverse reactions occurred in 58% of patients who received IMDELLTRA. Serious adverse reactions in >3% of patients included cytokine release syndrome (24%), pneumonia (6%), pyrexia (3.7%) and hyponatremia (3.6%). Fatal adverse reactions occurred in 2.7% of patients who received IMDELLTRA including pneumonia 0.5%, aspiration (0.5%), pulmonary embolism (0.5%), respiratory acidosis (0.5%), and respiratory failure (0.5%).

Permanent discontinuation of IMDELLTRA due to an adverse reaction occurred in 7% of patients. Adverse reactions which resulted in permanent discontinuation of IMDELLTRA in >1% of patients included cytokine release syndrome (1.6%) and tumor lysis syndrome (1.1%).

Dosage interruptions of IMDELLTRA due to an adverse reaction occurred in 27% of patients. Adverse reactions which required dosage interruption in ≥ 2% of patients included fatigue (3.2%), cytokine release syndrome (2 .7%) and respiratory tract infection (2.1%).

Table 15 summarizes adverse reactions observed in DeLLphi-300 and DeLLphi-301.