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%).
Extensive Stage Small Cell Lung Cancer
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 [see Clinical Studies (14.1)]. Patients received IMDELLTRA (n=252) or investigator's choice of topotecan [n=176], lurbinectedin [n=45] or amrubicin [n=23].
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.
Table 13. Adverse Reactions (≥ 15%) in Patients with SCLC Who Received IMDELLTRA in DeLLphi-304| Adverse Reaction | IMDELLTRA Graded using CTCAE Version 4.0 and Version 5.0. (N = 252) | Standard of Care (N = 244) |
|---|
| Any Grade (%) | Grade 3 or 4 (%) | Any Grade (%) | Grade 3 or 4 (%) |
|---|
| Immune system disorders |
| Cytokine release syndrome Based on American Society for Transplantation and Cellular Therapy (ASTCT) 2019. | 56 | 1.2 | 1.2 | 0 |
| General disorders and administration site conditions |
| Fatigue Includes fatigue and asthenia | 39 | 6 | 43 | 10 |
| Pyrexia Includes body temperature increased, hyperthermia, pyrexia | 29 | 1.2 | 11 | 1.2 |
| Metabolism and nutrition disorders |
| Decreased appetite | 37 | 2 | 23 | 1.6 |
| Gastrointestinal disorders |
| Constipation | 30 | 0.4 | 22 | 0 |
| Nausea | 25 | 0.4 | 32 | 0 |
| Nervous system disorders |
| Dysgeusia Includes ageusia, dysgeusia, hypogeusia | 28 | 0 | 2.5 | 0 |
| Headache Includes headache and tension headache | 16 | 0 | 9 | 0 |
| Musculoskeletal and connective tissue disorders |
| Musculoskeletal pain Includes arthralgia, back pain, bone pain, musculoskeletal pain, myalgia, neck pain, non-cardiac chest pain, pain in extremity, spinal pain | 27 | 1.6 | 21 | 2.5 |
| Respiratory, thoracic and mediastinal disorders |
| Cough Includes cough and productive cough | 17 | 0 | 17 | 0 |
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.
Table 14. Laboratory Abnormalities (≥ 20%) That Worsened from Baseline in Patients with SCLC in DeLLphi-304| Laboratory Abnormality | IMDELLTRA The denominator used to calculate the rate varied for IMDELLTRA (Range: 229 to 250) and SOC (Range: 205 to 226) based on the number of patients with a baseline value and at least one post-treatment value. N=252 | Standard of care N=244 |
|---|
All Grades (%) | Grade 3 or 4 (%) | All Grades (%) | Grade 3 or 4 (%) |
|---|
| Hematology |
| Lymphocytes decreased | 65 | 27 | 62 | 27 |
| Hemoglobin decreased | 51 | 4.5 | 86 | 29 |
| White blood cells decreased | 50 | 7 | 70 | 29 |
| Platelets decreased | 25 | 0.4 | 55 | 20 |
| Neutrophils decreased All Grade lab abnormalities occurring at a frequency less than 20% included decreased neutrophils. | 15 | 10 | 44 | 36 |
| Chemistry |
| Sodium decreased | 57 | 8 | 38 | 7 |
| Potassium decreased | 41 | 4.8 | 34 | 4 |
| Aspartate amino transferase increased | 40 | 2.8 | 29 | 0.4 |
| Sodium increased | 35 | 0.4 | 27 | 0 |
| Alanine aminotransferase increased | 32 | 2 | 25 | 0.9 |
| Activated Partial Thromboplastin Time (sec) increased | 26 | 1.3 | 16 | 0.9 |
| Creatinine increased | 23 | 0.8 | 19 | 0.4 |
| Alkaline phosphate increased | 22 | 0.4 | 26 | 1.4 |
| Magnesium decreased | 21 | 0.8 | 15 | 1.8 |
| Potassium increased | 21 | 0.8 | 12 | 1.8 |
| Creatine Phosphokinase increased | 21 | 1.7 | 11 | 0 |
DeLLphi-300 and DeLLphi-301
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 [see Clinical Studies (14.1)]. Among 187 patients who received IMDELLTRA, 31% were exposed for 6 months or longer and 14% were exposed for greater than one year.
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.
Table 15. Adverse Reactions (≥ 15%) in Patients with ES-SCLC Who Received IMDELLTRA in DeLLphi-300 and DeLLphi-301| Adverse Reaction | IMDELLTRA Graded using CTCAE Version 4.0 and Version 5.0. (N = 187) |
|---|
Any Grade (%) | Grade 3 or 4 (%) |
|---|
| Immune system disorders |
| Cytokine release syndrome Based on American Society for Transplantation and Cellular Therapy (ASTCT) 2019. | 55 | 1.6 |
| General disorders and administration site conditions |
| Fatigue Includes fatigue and asthenia. | 51 | 10 |
| Pyrexia | 36 | 0 |
| Nervous system disorders |
| Dysgeusia | 36 | 0 |
| Metabolism and nutrition disorders |
| Decreased appetite | 34 | 2.7 |
| Nausea | 22 | 1.6 |
| Gastrointestinal disorders |
| Constipation | 30 | 0.5 |
| Musculoskeletal and connective tissue disorders |
| Musculoskeletal pain Includes myalgia, arthralgia, back pain, pain in extremity, neck pain, musculoskeletal chest pain, non- cardiac chest pain and bone pain. | 30 | 1.1 |
| Respiratory, thoracic and mediastinal disorders |
| Dyspnea Includes dyspnea and exertional dyspnea. | 17 | 2.1 |
| Cough | 17 | 0 |
Table 16 summarizes laboratory abnormalities in DeLLphi-300 and DeLLphi-301.
Table 16. Laboratory Abnormalities (≥ 20%) That Worsened from Baseline in Patients with ES - SCLC in DeLLphi-300 and DeLLphi-301 | IMDELLTRA The denominator used to calculate the rate varied from 41 to 187 based on the number of patients with a baseline value and at least one post-treatment value. |
|---|
| | All Grades (%) | Grade 3 or 4 (%) |
|---|
| Laboratory Abnormality | | |
|---|
| Hematology |
| Lymphocytes decreased | 84 | 57 |
| Hemoglobin decreased | 58 | 5 |
| White blood cells decreased | 44 | 3.8 |
| Platelets decreased | 33 | 3.2 |
| Neutrophils decreased All Grade lab abnormalities occurring at a frequency less than 20% included decreased neutrophils. | 12 | 6 |
| Chemistry |
| Sodium decreased | 68 | 16 |
| Potassium decreased | 50 | 5 |
| Aspartate amino transferase increased | 44 | 3.2 |
| Alanine aminotransferase increased | 42 | 2.1 |
| Magnesium decreased | 33 | 1.6 |
| Creatinine increased | 29 | 0.5 |
| Sodium increased | 26 | 0 |
| Alkaline phosphate increased | 22 | 0 |