ADVERSE REACTIONS
The following adverse reactions are discussed in greater detail in other sections of the label:
- Infusion reactions [See
Boxed Warning
, Warnings and Precautions
.]
- Cardiopulmonary arrest [See
Boxed Warning
, Warnings and Precautions
.]
- Pulmonary toxicity [See Warnings and Precautions
.]
- Dermatologic toxicity [See Warnings and Precautions
.]
- Hypomagnesemia and Electrolyte Abnormalities [See Warnings and Precautions
.]
The most common adverse reactions in Erbitux clinical trials (incidence ≥25%) include cutaneous adverse reactions (including rash, pruritus, and nail changes), headache, diarrhea, and infection.
The most serious adverse reactions with Erbitux are infusion reactions, cardiopulmonary arrest, dermatologic toxicity and radiation dermatitis, sepsis, renal failure, interstitial lung disease, and pulmonary embolus.
Across Studies 1, 3, 5, and 6, Erbitux was discontinued in 3–10% of patients because of adverse reactions.
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.
The data below reflect exposure to Erbitux in 1373 patients with SCCHN or colorectal cancer in randomized Phase 3 (Studies 1 and 5) or Phase 2 (Studies 3 and 6) trials treated at the recommended dose and schedule for medians of 7 to 14 weeks. [See Clinical Studies
.]
Infusion reactions: Infusion reactions, which included pyrexia, chills, rigors, dyspnea, bronchospasm, angioedema, urticaria, hypertension, and hypotension occurred in 15–21% of patients across studies. Grades 3 and 4 infusion reactions occurred in 2–5% of patients; infusion reactions were fatal in 1 patient.
Infections: The incidence of infection was variable across studies, ranging from 13–35%. Sepsis occurred in 1–4% of patients.
Renal: Renal failure occurred in 1% of patients with colorectal cancer.
Squamous Cell Carcinoma of the Head and Neck
Erbitux in Combination with Radiation Therapy
Table 2 contains selected adverse reactions in 420 patients receiving radiation therapy either alone or with Erbitux for locally or regionally advanced SCCHN in Study 1. Erbitux was administered at the recommended dose and schedule (400 mg/m2 initial dose, followed by 250 mg/m2 weekly). Patients received a median of 8 infusions (range 1–11).
Table 2: Incidence of Selected Adverse Reactions (≥10%) in Patients with Locoregionally Advanced SCCHN
Body System
Preferred Term |
Erbitux plus Radiation (n=208)
|
Radiation Therapy Alone (n=212)
|
Grades 1–4
|
Grades 3 and 4
|
Grades 1–4
|
Grades 3 and 4
|
% of Patients
|
a Includes cases also reported as infusion reaction. |
b Infusion reaction is defined as any event described at any time during the clinical study as “allergic reaction” or “anaphylactoid reaction”, or any event occurring on the first day of dosing described as “allergic reaction”, “anaphylactoid reaction”, “fever”, “chills”, “chills and fever”, or “dyspnea”. |
c Based on laboratory measurements, not on reported adverse reactions, the number of subjects with tested samples varied from 205–206 for Erbitux plus Radiation arm; 209–210 for Radiation alone. |
d Acneiform rash is defined as any event described as “acne”, “rash”, “maculopapular rash”, “pustular rash”, “dry skin”, or “exfoliative dermatitis”. |
Body as a Whole
|
|
|
|
|
Asthenia |
56 |
4 |
49 |
5 |
Fevera
|
29 |
1 |
13 |
1 |
Headache |
19 |
<1 |
8 |
<1 |
Infusion Reactionb
|
15 |
3 |
2 |
0 |
Infection |
13 |
1 |
9 |
1 |
Chillsa
|
16 |
0 |
5 |
0 |
Digestive
|
|
|
|
|
Nausea |
49 |
2 |
37 |
2 |
Emesis |
29 |
2 |
23 |
4 |
Diarrhea |
19 |
2 |
13 |
1 |
Dyspepsia |
14 |
0 |
9 |
1 |
Metabolic/Nutritional
|
|
|
|
|
Weight Loss |
84 |
11 |
72 |
7 |
Dehydration |
25 |
6 |
19 |
8 |
Alanine Transaminase, highc
|
43 |
2 |
21 |
1 |
Aspartate Transaminase, highc
|
38 |
1 |
24 |
1 |
Alkaline Phosphatase, highc
|
33 |
<1 |
24 |
0 |
Respiratory
|
|
|
|
|
Pharyngitis |
26 |
3 |
19 |
4 |
Skin/Appendages
|
|
|
|
|
Acneiform Rashd
|
87 |
17 |
10 |
1 |
Radiation Dermatitis |
86 |
23 |
90 |
18 |
Application Site Reaction |
18 |
0 |
12 |
1 |
Pruritus |
16 |
0 |
4 |
0 |
The incidence and severity of mucositis, stomatitis, and xerostomia were similar in both arms of the study.
Late Radiation Toxicity
The overall incidence of late radiation toxicities (any grade) was higher in Erbitux in combination with radiation therapy compared with radiation therapy alone. The following sites were affected: salivary glands (65% versus 56%), larynx (52% versus 36%), subcutaneous tissue (49% versus 45%), mucous membrane (48% versus 39%), esophagus (44% versus 35%), skin (42% versus 33%). The incidence of Grade 3 or 4 late radiation toxicities was similar between the radiation therapy alone and the Erbitux plus radiation treatment groups.
Study 2: EU-Approved Cetuximab in Combination with Platinum-based Therapy with 5-Fluorouracil
Study 2 used EU-approved cetuximab. Since U.S.-licensed Erbitux provides approximately 22% higher exposure relative to the EU-approved cetuximab, the data provided below may underestimate the incidence and severity of adverse reactions anticipated with Erbitux for this indication. However, the tolerability of the recommended dose is supported by safety data from additional studies of Erbitux [see Clinical Pharmacology
].
Table 3 contains selected adverse reactions in 434 patients with recurrent locoregional disease or metastatic SCCHN receiving EU-approved cetuximab in combination with platinum-based therapy with 5-FU or platinum-based therapy with 5-FU alone in Study 2. Cetuximab was administered at 400 mg/m2 for the initial dose, followed by 250 mg/m2 weekly. Patients received a median of 17 infusions (range 1–89).
Table 3: Incidence of Selected Adverse Reactions (≥10%) in Patients with Recurrent Locoregional Disease or Metastatic SCCHN
System Organ Class
Preferred Term |
EU-Approved Cetuximab plus Platinum-based Therapy with 5-FU (n=219)
|
Platinum-based Therapy with 5-FU Alone (n=215)
|
Grades 1–4
|
Grades 3 and 4
|
Grades 1–4
|
Grades 3 and 4
|
% of Patients
|
a Infusion reaction defined as any event of “anaphylactic reaction”, “hypersensitivity”, “fever and/or chills”, “dyspnea”, or “pyrexia” on the first day of dosing. |
b Infection – this term excludes sepsis-related events which are presented separately. |
c Acneiform rash defined as any event described as “acne”, “dermatitis acneiform”, “dry skin”, “exfoliative rash”, “rash”, “rash erythematous”, “rash macular”, “rash papular”, or “rash pustular”. |
Chemotherapy = cisplatin + 5-fluorouracil or carboplatin + 5-fluorouracil |
Eye Disorders
|
|
|
|
|
Conjunctivitis |
10 |
0 |
0 |
0 |
Gastrointestinal Disorders
|
|
|
|
|
Nausea |
54 |
4 |
47 |
4 |
Diarrhea |
26 |
5 |
16 |
1 |
General Disorders and Administration Site Conditions
|
|
|
|
|
Pyrexia |
22 |
0 |
13 |
1 |
Infusion Reactiona
|
10 |
2 |
<1 |
0 |
Infections and Infestations
|
|
|
|
|
Infectionb
|
44 |
11 |
27 |
8 |
Metabolism and Nutrition Disorders
|
|
|
|
|
Anorexia |
25 |
5 |
14 |
1 |
Hypocalcemia |
12 |
4 |
5 |
1 |
Hypokalemia |
12 |
7 |
7 |
5 |
Hypomagnesemia |
11 |
5 |
5 |
1 |
Skin and Subcutaneous Tissue Disorders
|
|
|
|
|
Acneiform Rashc
|
70 |
9 |
2 |
0 |
Rash |
28 |
5 |
2 |
0 |
Acne |
22 |
2 |
0 |
0 |
Dermatitis Acneiform |
15 |
2 |
0 |
0 |
Dry Skin |
14 |
0 |
<1 |
0 |
Alopecia |
12 |
0 |
7 |
0 |
For cardiac disorders, approximately 9% of subjects in both the EU-approved cetuximab plus chemotherapy and chemotherapy-only treatment arms in Study 2 experienced a cardiac event. The majority of these events occurred in patients who received cisplatin/5-FU, with or without cetuximab as follows: 11% and 12% in patients who received cisplatin/5-FU with or without cetuximab, respectively, and 6% or 4% in patients who received carboplatin/5-FU with or without cetuximab, respectively. In both arms, the incidence of cardiovascular events was higher in the cisplatin with 5-FU containing subgroup. Death attributed to cardiovascular event or sudden death was reported in 3% of the patients in the cetuximab plus platinum-based therapy with 5-FU arm and 2% in the platinum-based chemotherapy with 5-FU alone arm.
Colorectal Cancer
Study 4: EU-Approved Cetuximab in Combination with FOLFIRI
Study 4 used EU-approved cetuximab. U.S.-licensed Erbitux provides approximately 22% higher exposure to cetuximab relative to the EU-approved cetuximab. The data provided below for Study 4 is consistent in incidence and severity of adverse reactions with those seen for Erbitux in this indication. The tolerability of the recommended dose is supported by safety data from additional studies of Erbitux [see Clinical Pharmacology
].
Table 4 contains selected adverse reactions in 667 patients with K-Ras mutation-negative (wild-type), EGFR-expressing, metastatic colorectal cancer receiving EU-approved cetuximab plus FOLFIRI or FOLFIRI alone in Study 4 [see Warnings and Precautions
]. Cetuximab was administered at the recommended dose and schedule (400 mg/m2 initial dose, followed by 250 mg/m2 weekly). Patients received a median of 26 infusions (range 1–224).
Table 4: Incidence of Selected Adverse Reactions Occurring in ≥10% of Patients with K-Ras Mutation-negative (Wild-type) and EGFR-expressing, Metastatic Colorectal Cancera
Body System
Preferred Term |
EU-Approved Cetuximab plus FOLFIRI (n=317)
|
FOLFIRI Alone (n=350)
|
Grades 1–4b
|
Grades 3 and 4
|
Grades 1–4
|
Grades 3 and 4
|
% of Patients
|
a Adverse reactions occurring in at least 10% of Erbitux combination arm with a frequency at least 5% greater than that seen in the FOLFIRI arm. |
b Adverse reactions were graded using the NCI CTC, V 2.0. |
c Infusion related reaction is defined as any event meeting the medical concepts of allergy/anaphylaxis at any time during the clinical study or any event occurring on the first day of dosing and meeting the medical concepts of dyspnea and fever or by the following events using MedDRA preferred terms: “acute myocardial infarction”, “angina pectoris”, “angioedema”, “autonomic seizure”, “blood pressure abnormal”, “blood pressure decreased”, “blood pressure increased”, “cardiac failure”, “cardiopulmonary failure”, “cardiovascular insufficiency”, “clonus”, “convulsion”, “coronary no-reflow phenomenon”, “epilepsy”, “hypertension”, “hypertensive crisis”, “hypertensive emergency”, “hypotension”, “infusion related reaction”, “loss of consciousness”, “myocardial infarction”, “myocardial ischaemia”, “prinzmetal angina”, “shock”, “sudden death”, “syncope”, or “systolic hypertension”. |
d Acne-like rash is defined by the events using MedDRA preferred terms and included “acne”, “acne pustular”, “butterfly rash”, “dermatitis acneiform”, “drug rash with eosinophilia and systemic symptoms”, “dry skin”, “erythema”, “exfoliative rash”, “folliculitis”, “genital rash”, “mucocutaneous rash”, “pruritus”, “rash”, “rash erythematous”, “rash follicular”, “rash generalized”, “rash macular”, “rash maculopapular”, “rash maculovesicular”, “rash morbilliform”, “rash papular”, “rash papulosquamous”, “rash pruritic”, “rash pustular”, “rash rubelliform”, “rash scarlatiniform”, “rash vesicular”, “skin exfoliation”, “skin hyperpigmentation”, “skin plaque”, “telangiectasia”, or “xerosis”. |
Blood and Lymphatic System Disorders
|
|
|
|
|
Neutropenia |
49 |
31 |
42 |
24 |
Eye Disorders
|
|
|
|
|
Conjunctivitis |
18 |
<1 |
3 |
0 |
Gastrointestinal Disorders
|
|
|
|
|
Diarrhea |
66 |
16 |
60 |
10 |
Stomatitis |
31 |
3 |
19 |
1 |
Dyspepsia |
16 |
0 |
9 |
0 |
General Disorders and Administration Site Conditions
|
|
|
|
|
Infusion-related Reactionc
|
14 |
2 |
<1 |
0 |
Pyrexia |
26 |
1 |
14 |
1 |
Infections and Infestations
|
|
|
|
|
Paronychia |
20 |
4 |
<1 |
0 |
Investigations
|
|
|
|
|
Weight Decreased |
15 |
1 |
9 |
1 |
Metabolism and Nutrition Disorders
|
|
|
|
|
Anorexia |
30 |
3 |
23 |
2 |
Skin and Subcutaneous Tissue Disorders
|
|
|
|
|
Acne-like Rashd
|
86 |
18 |
13 |
<1 |
Rash |
44 |
9 |
4 |
0 |
Dermatitis Acneiform |
26 |
5 |
<1 |
0 |
Dry Skin |
22 |
0 |
4 |
0 |
Acne |
14 |
2 |
0 |
0 |
Pruritus |
14 |
0 |
3 |
0 |
Palmar-plantar Erythrodysesthesia Syndrome |
19 |
4 |
4 |
<1 |
Skin Fissures |
19 |
2 |
1 |
0 |
Erbitux Monotherapy
Table 5 contains selected adverse reactions in 242 patients with K-Ras mutation-negative (wild-type), EGFR-expressing, metastatic colorectal cancer who received best supportive care (BSC) alone or with Erbitux in Study 5 [see Warnings and Precautions
]. Erbitux was administered at the recommended dose and schedule (400 mg/m2 initial dose, followed by 250 mg/m2 weekly). Patients received a median of 17 infusions (range 1–51).
Table 5: Incidence of Selected Adverse Reactions Occurring in ≥10% of Patients with K-Ras Mutation-negative (Wild-type), EGFR-expressing, Metastatic Colorectal Cancer Treated with Erbitux Monotherapya
Body System
Preferred Term |
Erbitux plus BSC (n=118)
|
BSC alone (n=124)
|
Grades 1–4b
|
Grades 3 and 4
|
Grades 1–4
|
Grades 3 and 4
|
% of Patients
|
a Adverse reactions occurring in at least 10% of Erbitux plus BSC arm with a frequency at least 5% greater than that seen in the BSC alone arm. |
b Adverse reactions were graded using the NCI CTC, V 2.0. |
c Infusion reaction is defined as any event (chills, rigors, dyspnea, tachycardia, bronchospasm, chest tightness, swelling, urticaria, hypotension, flushing, rash, hypertension, nausea, angioedema, pain, sweating, tremors, shaking, drug fever, or other hypersensitivity reaction) recorded by the investigator as infusion-related. |
Dermatology/Skin
|
|
|
|
|
Rash/Desquamation |
95 |
16 |
21 |
1 |
Dry Skin |
57 |
0 |
15 |
0 |
Pruritus |
47 |
2 |
11 |
0 |
Other-Dermatology |
35 |
0 |
7 |
2 |
Nail Changes |
31 |
0 |
4 |
0 |
Constitutional Symptoms
|
|
|
|
|
Fatigue |
91 |
31 |
79 |
29 |
Fever |
25 |
3 |
16 |
0 |
Infusion Reactionsc
|
18 |
3 |
0 |
0 |
Rigors, Chills |
16 |
1 |
3 |
0 |
Pain
|
|
|
|
|
Pain-Other |
59 |
18 |
37 |
10 |
Headache |
38 |
2 |
11 |
0 |
Bone Pain |
15 |
4 |
8 |
2 |
Pulmonary
|
|
|
|
|
Dyspnea |
49 |
16 |
44 |
13 |
Cough |
30 |
2 |
19 |
2 |
Gastrointestinal
|
|
|
|
|
Nausea |
64 |
6 |
50 |
6 |
Constipation |
53 |
3 |
38 |
3 |
Diarrhea |
42 |
2 |
23 |
2 |
Vomiting |
40 |
5 |
26 |
5 |
Stomatitis |
32 |
1 |
10 |
0 |
Other-Gastrointestinal |
22 |
12 |
16 |
5 |
Dehydration |
13 |
5 |
3 |
0 |
Mouth Dryness |
12 |
0 |
6 |
0 |
Taste Disturbance |
10 |
0 |
5 |
0 |
Infection
|
|
|
|
|
Infection without neutropenia |
38 |
11 |
19 |
5 |
Musculoskeletal
|
|
|
|
|
Arthralgia |
14 |
3 |
6 |
0 |
Neurology
|
|
|
|
|
Neuropathy-sensory |
45 |
1 |
38 |
2 |
Insomnia |
27 |
0 |
13 |
0 |
Confusion |
18 |
6 |
10 |
2 |
Anxiety |
14 |
1 |
5 |
1 |
Depression |
14 |
0 |
5 |
0 |
Erbitux in Combination with Irinotecan
The most frequently reported adverse reactions in 354 patients treated with Erbitux plus irinotecan in clinical trials were acneiform rash (88%), asthenia/malaise (73%), diarrhea (72%), and nausea (55%). The most common Grades 3–4 adverse reactions included diarrhea (22%), leukopenia (17%), asthenia/malaise (16%), and acneiform rash (14%).
Immunogenicity
As with all therapeutic proteins, there is potential for immunogenicity. Immunogenic responses to cetuximab were assessed using either a double antigen radiometric assay or an ELISA assay. Due to limitations in assay performance and sampling timing, the incidence of antibody development in patients receiving Erbitux has not been adequately determined. Non-neutralizing anti-cetuximab antibodies were detected in 5% (49 of 1001) of evaluable patients without apparent effect on the safety or antitumor activity of Erbitux.
The incidence of antibody formation is highly dependent on the sensitivity and specificity of the assay. Additionally, the observed incidence of antibody (including neutralizing antibody) positivity in an assay may be influenced by several factors including assay methodology, sample handling, timing of sample collection, concomitant medications, and underlying disease. For these reasons, comparison of the incidence of antibodies to Erbitux with the incidence of antibodies to other products may be misleading.
Postmarketing Experience
The following adverse reactions have been identified during post-approval use of Erbitux. Because these reactions are reported from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
- Aseptic meningitis
- Mucosal inflammation
|