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 safety data described in this section reflect exposure to KYMRIAH in the clinical trial (Study 1) in which 68 patients with pediatric and young adult relapsed/ refractory (R/R) B-cell ALL received CAR-positive viable T cells.
Based on a recommended dose which was weight-based, all patients received a single intravenous dose of KYMRIAH [see Clinical Studies (14)]. The most common adverse reactions were cytokine release syndrome (79%), hypogammaglobulinemia (43%), infections-pathogen unspecified (41%), pyrexia (40%), decreased appetite (37%), headache (37%), encephalopathy (34%), hypotension (31%), bleeding episodes (31%), tachycardia (26%), nausea (26%), diarrhea (26%), vomiting (26%), viral infectious disorders (26%), hypoxia (24%), fatigue (22%), acute kidney injury (22%), and delirium (21%).
Eleven deaths were reported for patients who received KYMRIAH, of which 2 deaths occurred within 30 days of infusion. Seven were disease-related, three were attributed to infections, and one to intracerebral hemorrhage. Of the two deaths before Day 30, one patient died with CRS and progressive leukemia and the second patient had resolving CRS with abdominal compartment syndrome, coagulopathy, and renal failure when an intracranial hemorrhage occurred.
The adverse reactions with greater or equal to 10% incidence for any Grade are summarized in Table 2.
Table 2. Selected Adverse Reactions (≥ 10%) Following Treatment with KYMRIAH (N=68)| Adverse Reaction | All Grades (%) | Grades 3 or Higher (%) |
| Cardiac disorders | | |
| aTachycardia | 26 | 4 |
| Gastrointestinal disorders | | |
| Nausea | 26 | 3 |
| Diarrhea | 26 | 1 |
| Vomiting | 26 | 1 |
| Constipation | 18 | 0 |
| bAbdominal pain | 16 | 3 |
| General disorders and administration site conditions | | |
| Pyrexia | 40 | 15 |
| Fatigue | 22 | 0 |
| Face edema | 10 | 1 |
| Edema peripheral | 10 | 1 |
| Chills | 10 | 0 |
| Immune system disorders | | |
| Cytokine release syndrome | 79 | 49 |
| cHypogammaglobulinemia | 43 | 7 |
| Infections and infestations | | |
| Infections-pathogen unspecified | 41 | 16 |
| Viral infectious disorders | 26 | 18 |
| Bacterial infectious disorders | 19 | 13 |
| Fungal infectious disorders | 13 | 7 |
| Investigations | | |
| International normalized ratio increased | 13 | 0 |
| Metabolism and nutrition disorders | | |
| Decreased appetite | 37 | 15 |
| Fluid overload | 10 | 7 |
| Musculoskeletal and connective tissue disorders | | |
| Pain in extremity | 16 | 1 |
| Myalgia | 15 | 0 |
| Arthralgia | 12 | 1 |
| Back pain | 10 | 3 |
| Nervous system disorders | | |
| dHeadache | 37 | 3 |
| eEncephalopathy | 34 | 10 |
| Psychiatric disorders | | |
| fDelirium | 21 | 4 |
| Anxiety | 13 | 3 |
| Renal and urinary disorders | | |
| gAcute kidney injury | 22 | 13 |
| Respiratory, thoracic and mediastinal disorders | | |
| Hypoxia | 24 | 18 |
| Cough | 19 | 0 |
| Pulmonary edema | 16 | 10 |
| Tachypnea | 12 | 6 |
| Pleural effusion | 10 | 4 |
| Nasal congestion | 10 | 0 |
| Vascular disorders | | |
| Hypotension | 31 | 22 |
| Hypertension | 19 | 6 |
aTachycardia includes tachycardia and sinus tachycardia. bAbdominal pain includes abdominal pain, abdominal pain upper, gastrointestinal pain, abdominal pain lower. cHypogammaglobulinemia includes hypogammaglobulinemia, immunoglobulins decreased, blood immunoglobulin G decreased, blood immunoglobulin A decreased, blood immunoglobulin M decreased, hypogammaglobulinemia. dHeadache includes headache and migraine. eEncephalopathy includes encephalopathy, cognitive disorder, confusional state, depressed level of consciousness, disturbance in attention, lethargy, mental status changes, posterior reversible encephalopathy syndrome, somnolence, and automatism. fDelirium includes delirium, agitation, hallucination, hallucination visual, irritability, restlessness. gAcute kidney injury includes acute kidney injury, anuria, azotemia, renal failure, renal tubular dysfunction, renal tubular necrosis. |
Additional important adverse reactions that did not meet the threshold criteria for inclusion in Table 2 were:
Blood and lymphatic system disorders: disseminated intravascular coagulation (9%), histiocytosis lymphocytic hemophagocytosis (7%), coagulopathy (6%), Grade 3 and Grade 4 hypofibrinogenemia with Grade 3 and 4 CRS (16%)
Cardiac Disorders: cardiac arrest (4%), cardiac failure (7%)
Gastrointestinal disorders: abdominal compartment syndrome (1%)
General disorders and administration site conditions: multiple organ dysfunction syndrome (3%)
Immune system disorders: graft versus host disease (1%)
Investigations: blood creatinine increased (7%), activated partial thromboplastin time prolonged (6%)
Nervous System: intracranial hemorrhage (1%), seizure (3%)
Respiratory, thoracic, and mediastinal disorders: respiratory distress (6%), respiratory failure (6%), acute respiratory distress syndrome (4%)
Metabolism and nutrition disorders: tumor lysis syndrome (6%)
Vascular disorders: capillary leak syndrome (3%)
Laboratory Abnormalities
Selected laboratory abnormalities worsening from baseline Grade 0-2 to Grade 3-4 are shown in Table 3.
Table 3. Selected Other Laboratory Abnormalities Worsening from Baseline Grade 0-2 to Grade 3-4 Following Treatment with KYMRIAH based on CTCAEa (N=68) | Grade 3 or 4 (%) |
| Increased Aspartate Aminotransferase | 28 |
| Hypokalemia | 27 |
| Increased Alanine Aminotransferase | 21 |
| Increased bilirubin | 21 |
| Hypophosphatemia | 19 |
| aCTCAE = Common Terminology Criteria for Adverse Events version 4.03 |
All patients experienced neutropenia, anemia and thrombocytopenia. See Table 4 for the incidences of Grade 3 and Grade 4 prolonged thrombocytopenia and prolonged neutropenia in responding patients.
Table 4. Prolonged Cytopenias Following Treatment with KYMRIAH | N=52 (%) |
| Day 28 | Day 56 |
| Prolonged neutropeniaa | 40 | 17 |
| Prolonged thrombocytopeniaa | 27 | 12 |
| aGrade 3 and 4 observed within 14 days after Day 28 or Day 56 in responding patients |