Summary of the safety profile
The safety of epcoritamab was evaluated in a non-randomised, single-arm GCT3013-01 study in 382 patients with relapsed or refractory large B-cell lymphoma (N=167), follicular lymphoma (N=129) and follicular lymphoma (3-step step-up dose schedule N=86) after two or more lines of systemic therapy and included all the patients who enrolled to the 48 mg dose and received at least one dose of epcoritamab.
The following adverse reactions have been reported with epcoritamab during clinical studies and post marketing experience.
The median duration of exposure to epcoritamab was 4.9 months (range: <1 to 30 months).
The most common adverse reactions (≥20%) were CRS (56%), injection site reactions (40%), fatigue (32%), viral infection (28%), neutropenia (28%), muscoskeletal pain (27%), pyrexia (22%), and diarrhoea (21%). The most common Grade 3-4 adverse reactions (≥2%) were neutropenia (23%), viral infections (9.2%), lymphopenia (8.9%), anaemia (7.1%), pneumonia (5.8%), thrombocytopenia (5.5%), fatigue (2.9%), febrile neutropenia (2.4%), and sepsis (2.4%).
Serious adverse reactions occurred in 50% of patients. The most common serious adverse reaction (≥10%) was CRS (34%). Fourteen patients (3.7%) experienced a fatal adverse reaction (pneumonia in 9 (2.4%) patients, viral infection in 4 (1.0%) patients, and ICANS in 1 (0.3%) patient).
Adverse reactions that led to discontinuation occurred in 6.8% of patients. Discontinuation of epcoritamab due to pneumonia occurred in 14 (3.7%) patients, viral infection in 8 (2.1%) patients, fatigue in 2 (0.5%) patients and CRS, ICANS, or diarrhoea occurred in 1 (0.3%) patient each.
Dose delays due to adverse reactions occurred in 42% of patients. Adverse reactions leading to dose delays (≥3% of patients) were viral infections (17%), CRS (11%), neutropenia (5.2%), pneumonia (4.7%), upper respiratory tract infection (4.2%) and pyrexia (3.7%).
Tabulated list of adverse reactions
Adverse reactions for epcoritamab from clinical studies (Table 7) are listed by MedDRA system organ class and are based on the following convention: very common (≥ 1/10); common (≥ 1/100 to < 1/10); uncommon (≥ 1/1 000 to < 1/100); rare (≥ 1/10 000 to < 1/1 000); and very rare (< 1/10 000).
Table 7 Adverse reactions reported in patients with relapsed or refractory LBCL or FL treated with epcoritamab
| System organ class / preferred term or adverse reaction | All grades | Grade 3-4 |
| Infections and infestations |
| Viral infectiona | Very common | Common |
| Pneumoniab | Very common | Common |
| Upper respiratory tract infectionc | Very common | Common |
| Fungal infectiond | Common | |
| Sepsise | Common | Common |
| Cellulitis | Common | Common |
| Neoplasms benign, malignant and unspecified (incl cysts and polyps) |
| Tumour flare | Common | |
| Blood and lymphatic system disorders |
| Neutropeniaf | Very common | Very common |
| Anaemiag | Very common | Common |
| Thrombocytopeniah | Very common | Common |
| Lymphopeniai | Very common | Common |
| Febrile neutropenia | Common | Common |
| Haemophagocytic lymphohistiocytosisj | Uncommon | Rare |
| Immune system disorders |
| Cytokine release syndromej | Very common | Common |
| Hypogammaglobulinaemia | Very common | Uncommon |
| Metabolism and nutrition disorders |
| Decreased appetite | Very common | Uncommon |
| Hypokalaemia | Common | Common |
| Hypophosphatemia | Common | Common |
| Hypomagnesaemia | Common | Uncommon |
| Tumour lysis syndromek | Common | Uncommon |
| Nervous system disorders |
| Headache | Very common | Uncommon |
| Immune effector cell-associated neurotoxicity syndromej | Common | |
| Cardiac disorders |
| Cardiac arrhythmiasl | Common | Uncommon |
| Respiratory, thoracic and mediastinal disorders |
| Pleural effusion | Common | Common |
| Gastrointestinal disorders |
| Diarrhoea | Very common | Uncommon |
| Abdominal Painm | Very common | Common |
| Nausea | Very common | Uncommon |
| Vomiting | Common | Uncommon |
| Skin and subcutaneous tissue disorders |
| Rashn | Very common | |
| Pruritus | Common | |
| Musculoskeletal and connective tissue disorders |
| Musculoskeletal paino | Very common | Common |
| General disorders and administration site conditions |
| Injection site reactionsp | Very common | |
| Fatigueq | Very common | Common |
| Pyrexiar | Very common | Common |
| Oedemas | Very common | Common |
| Investigations |
| Alanine aminotransferase increased | Common | Common |
| Aspartate aminotransferase increased | Common | Common |
| Blood creatinine increased | Common | |
| Blood sodium decreasedt | Common | Uncommon |
| Alkaline phosphatase increased | Common | |
| Adverse reactions were graded using NCI CTCAE version 5.0 a Viral infection includes COVID-19, cytomegalovirus chorioretinitis, cytomegalovirus colitis, cytomegalovirus infection, cytomegalovirus infection reactivation, gastroenteritis viral, herpes simplex, herpes simplex reactivation, herpes virus infection, herpes zoster, oral herpes, post-acute COVID-19 syndrome, and varicella zoster virus infection b Pneumonia includes COVID-19 pneumonia and pneumonia c Upper respiratory tract infection includes laryngitis, pharyngitis, respiratory syncytial virus infection, rhinitis, rhinovirus infection, and upper respiratory tract infection d Fungal infection includes candida infection, oesophageal candidiasis, oral candidiasis and oropharyngeal candidiasis e Sepsis includes bacteraemia, sepsis, and septic shock f Neutropenia includes neutropenia and neutrophil count decreased g Anaemia includes anaemia and serum ferritin decreased h Thrombocytopenia includes platelet count decreased and thrombocytopenia i Lymphopenia includes lymphocyte count decreased and lymphopenia j Events graded using American Society for Transplantation and Cellular Therapy (ASTCT) consensus criteria k Clinical Tumour Lysis Syndrome was graded based on Cairo-Bishop l Cardiac arrhythmias include bradycardia, sinus bradycardia, sinus tachycardia, supraventricular tachycardia, and tachycardia m Abdominal pain includes abdominal discomfort, abdominal pain, abdominal pain lower, abdominal pain upper, and abdominal tenderness n Rash includes rash, rash erythematous, rash macular, rash maculo-papular, rash popular, rash pruritic, rash pustular and rash vesicular o Musculoskeletal pain includes back pain, bone pain, flank pain, musculoskeletal chest pain, musculoskeletal pain, myalgia, neck pain, non-cardiac chest pain, pain, pain in extremity, and spinal pain p Injection site reactions include injection site bruising, injection site erythema, injection site hypertrophy, injection site inflammation, injection site mass, injection site nodule, injection site oedema, injection site pain, injection site pruritus, injection site rash, injection site reaction, injection site swelling, and injection site urticaria q Fatigue includes asthenia, fatigue, and lethargy r Pyrexia includes body temperature increased and pyrexia s Oedema includes face oedema, generalized oedema, oedema, oedema peripheral, peripheral swelling, swelling, and swelling face t Blood sodium decreased includes blood sodium decreased and hyponatraemia |
Description of selected adverse reactions
Cytokine release syndrome
2-step step-up dose schedule (large B-cell lymphoma and follicular lymphoma)
In study GCT3013-01, CRS of any grade occurred in 58% (171/296) of patients with large B-cell lymphoma and follicular lymphoma treated with epcoritamab at the 2-step step-up dose schedule. The incidence of Grade 1 was 35%, Grade 2 was 21%, and Grade 3 occurred in 2.4% of patients. Recurrent CRS occurred in 21% of patients with CRS. CRS of any grade occurred in 9.8% of patients after the priming dose (Cycle 1 Day 1); 13% after the intermediate dose (Cycle 1 Day 8); 51% after the first full dose (Cycle 1 Day 15); 6.5% after the second full dose (Cycle 1 Day 22); and 3.7% after the third full dose (Cycle 2 Day 1) or beyond. The median time to onset of CRS from the most recent administered epcoritamab dose was 2 days (range: 1 to 12 days). The median time to onset after the first full dose was 19.3 hours (range: <0.1 days to 7 days). CRS resolved in 99% of events, and the median duration of CRS events was 2 days (range 1 to 54 days).
Dose delays due to CRS occurred in 9.1% of patients. Treatment was discontinued in 0.3% of patients due to CRS.
Of the 171 patients that experienced CRS, the most common signs and symptoms of CRS included pyrexia (99%), hypotension (32%) and hypoxia (16%). Other signs and symptoms of CRS in ≥3% of patients included chills (11%), tachycardia (including sinus tachycardia (11%)), headache (8.2%), nausea (4.7%), and vomiting (4.1%). Tocilizumab was used to manage the CRS event in 19% of patients, and corticosteroids were used in 12% of patients. Out of the 67 events treated with tocilizumab, 84% responded within four (4) days of treatment.
Hospitalizations due to CRS occurred in 34% of patients and the median time to CRS resolution in those who were hospitalized was 1 day (range <1 to 26 days).
3-step step-up dose schedule follicular lymphoma
In study GCT3013-01, CRS of any grade occurred in 49% (42/86) of patients treated with epcoritamab at the recommended follicular lymphoma 3-step step-up dose schedule. The incidence of Grade 1 was 40% and Grade 2 was 9%. There were no Grade ≥3 CRS events reported. Recurrent CRS occurred in 23% of patients. Most CRS events occurred during Cycle 1, where 48% of patients experienced an event. In Cycle 1, CRS occurred in 12% of patients after the priming dose (Cycle 1 Day 1), 5.9% of patients after the intermediate dose (Cycle 1 Day 8), 15% of patients after the second intermediate dose (Cycle 1 Day 15), and 37% of patients after the first full dose (Cycle 1 Day 22). The median time to onset of CRS from the most recent administered epcoritamab dose was 59 hours (range: 1 to 8 days). The median time to onset after the first full dose was 61 hours (range: 1 to 8 days). CRS resolved in 100% of patients and the median duration of CRS events was 2 days (range 1 to 14 days).
Serious adverse reactions due to CRS occurred in 28% of patients who received epcoritamab.
Dose delays due to CRS occurred in 19% of patients who received epcoritamab.
Of the 42 patients that experienced CRS at the recommended dose, the most common (≥10%) signs and symptoms of CRS included pyrexia (100%) and hypotension (14%). In addition to corticosteroid use, tocilizumab was used to manage CRS event in 12% of patients.
Immune effector cell associated neurotoxicity syndrome
In study GCT3013-01, ICANS occurred in 4.7% (18/382) of patients treated with epcoritamab; 3.1% experienced Grade 1 and 1.3% experienced Grade 2. One patient (0.3%) experienced an ICANS event of Grade 5 (fatal). The median time to first ICANS onset from the start of epcoritamab treatment (Cycle 1 Day 1) was 18 days (range: 8 to 141 days). ICANS resolved in 94% (17/18) of patients with supportive care. The median time to resolution of ICANS was 2 days (range: 1 to 9 days).
Dose delays due to ICANS occurred in 1.0% of patients. Treatment was discontinued in 0.3% of patients due to ICANS.
Serious infections
Large B-cell lymphoma
In study GCT3013-01, serious infections of any grade occurred in 25% (41/167) of patients with large B-cell lymphoma treated with epcoritamab. The most frequent serious infections were COVID-19 (6.6%), COVID-19 pneumonia (4.2%), pneumonia (3.6%), sepsis (2.4%), cellulitis (1.8%), upper respiratory tract infection (1.8%), bacteraemia (1.2%), septic shock (1.2%), and progressive multifocal leukoencephalopathy (1.2%). The median time to onset of first serious infection was 56 days (range: 4 to 631 days), with median duration of 15 days (range: 4 to 125 days). Grade 5 events (fatal serious) of infections occurred in 7 (4.2%) patients.
Dose delays due to serious infections occurred in 15% of patients. Treatment was discontinued in 6.0% of patients due to serious infections (see Section 4.4).
Follicular lymphoma
In study GCT3013-01, serious infections of any grade occurred in 32% (68/215) of patients with follicular lymphoma treated with epcoritamab. The most frequent serious infections included COVID-19 (8.8%), COVID-19 pneumonia (5.6%), pneumonia (3.7%), urinary tract infection (1.9%), and Pneumocystis jirovecii pneumonia (1.4%). The median time to onset of first serious infection from the start of epcoritamab treatment (Cycle 1 Day 1) was 81 days (range: 1 to 636 days), with median duration of 18 days (range: 4 to 249 days). Grade 5 events of infection occurred in 8 (3.7%) patients, 6 (2.8%) of which were attributed to COVID-19 or COVID-19 pneumonia.
Immunogenicity
Epcoritamab has the potential to induce anti-product antibodies (ADA). The incidence of antibodies to epcoritamab was low and all the patients with LBCL who were ADA positive had low titres (≥1 in 0.6% (1/158)) and all the patients with FL who were ADA positive had titers <1. Due to the low number of patients with ADAs, a meaningful analysis of the impact of ADAs on safety is limited (see section 5.2).
Neutropenia
In study GCT3013-01, neutropenia of any grade occurred in 28% (105/382) of patients, including 23% Grade 3-4 events. The median time to onset of first neutropenia/neutrophil count decreased event was 65 days (range: 2 to 750 days), with median duration of 15 days (range: 2 to 415 days). Of the 105 patients who had neutropenia/neutrophil count decreased events, 61% received G-CSF to treat the events. Dose delays due to neutropenia occurred in 20 (5.2%) patients and there were no dose discontinuations due to neutropenia.
Tumour Lysis Syndrome
In study GCT3013-01, TLS occurred in 1.0% (4/382) of patients. Median time to onset was 18 days (range 8 to 33 days), and median duration was 3 days (range 2 to 4 days).
Tumour Flare
In study GCT3013-01, tumour flare occurred in 1.6% (6/382) of patients, all of which were grade 2. The median time to onset was 19.5 days (range 9 to 34 days), and median duration was 9 days (range 1 to 50 days).
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme: Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.