SIDE EFFECTS
The following adverse reactions
are discussed in greater detail in other sections of the label:
- Cardiomyopathy [see WARNINGS AND PRECAUTIONS]
- Infusion Reactions [see WARNINGS AND PRECAUTIONS]
- Embryo-Fetal Toxicity [see WARNINGS AND PRECAUTIONS]
- Pulmonary Toxicity [see WARNINGS AND PRECAUTIONS]
- Exacerbation of
Chemotherapy-induced Neutropenia [see WARNINGS
AND PRECAUTIONS]
The most common adverse
reactions in patients receiving trastuzumab products in the adjuvant and
metastatic breast cancer setting are fever, nausea, vomiting, infusion
reactions, diarrhea, infections, increased cough, headache, fatigue, dyspnea,
rash, neutropenia, anemia, and myalgia. Adverse reactions requiring
interruption or discontinuation of trastuzumab product treatment include CHF,
significant decline in left ventricular cardiac function, severe infusion
reactions, and pulmonary toxicity [see DOSAGE AND ADMINISTRATION].
In the metastatic gastric
cancer setting, the most common adverse reactions (≥ 10%) that were
increased (≥ 5% difference) in patients receiving trastuzumab as compared
to patients receiving chemotherapy alone were neutropenia, diarrhea, fatigue,
anemia, stomatitis, weight loss, upper respiratory tract infections, fever,
thrombocytopenia, mucosal inflammation, nasopharyngitis, and dysgeusia. The
most common adverse reactions which resulted in discontinuation of trastuzumab
treatment in the absence of disease progression were infection, diarrhea, and
febrile neutropenia.
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.
Adjuvant Breast Cancer Studies
The data below reflect exposure
to one-year trastuzumab therapy across three randomized, open-label studies,
Studies 1, 2, and 3, with (n = 3678) or without (n = 3363) trastuzumab in the
adjuvant treatment of breast cancer.
The data summarized in Table 3 below,
from Study 3, reflect exposure to trastuzumab in 1678 patients; the median
treatment duration was 51 weeks and median number of infusions was 18. Among
the 3386 patients enrolled in the observation and one-year trastuzumab arms of
Study 3 at a median duration of follow-up of 12.6 months in the trastuzumab
arm, the median age was 49 years (range: 21 to 80 years), 83% of patients were
Caucasian, and 13% were Asian.
Table 3 : Adverse Reactions for Study 3a,
All Gradesb
Adverse Reaction |
One Year Trastuzumab
(n= 1678) |
Observation
(n = 1708) |
Cardiac |
Hypertension |
64 (4%) |
35 (2%) |
Dizziness |
60 (4%) |
29 (2%) |
Ejection Fraction Decreased |
58 (3.5%) |
11 (0.6%) |
Palpitations |
48 (3%) |
12 (0.7%) |
Cardiac Arrhythmiasc |
40 (3%) |
17 (1%) |
Cardiac Failure Congestive |
30 (2%) |
5 (0.3%) |
Cardiac Failure |
9 (0.5%) |
4 (0.2%) |
Cardiac Disorder |
5 (0.3%) |
0 (0%) |
Ventricular Dysfunction |
4 (0.2%) |
0 (0%) |
Respiratory Thoracic Mediastinal Disorders |
Cough |
81 (5%) |
34 (2%) |
Influenza |
70 (4%) |
9 (0.5%) |
Dyspnea |
57 (3%) |
26 (2%) |
URI |
46 (3%) |
20 (1%) |
Rhinitis |
36 (2%) |
6 (0.4%) |
Pharyngolaryngeal Pain |
32 (2%) |
8 (0.5%) |
Sinusitis |
26 (2%) |
5 (0.3%) |
Epistaxis |
25 (2%) |
1 (0.06%) |
Pulmonary Hypertension |
4 (0.2%) |
0 (0%) |
Interstitial Pneumonitis |
4 (0.2%) |
0 (0%) |
Gastrointestinal Disorders |
Diarrhea |
123 (7%) |
16 (1%) |
Nausea |
108 (6%) |
19 (1%) |
Vomiting |
58 (3.5%) |
10 (0.6%) |
Constipation |
33 (2%) |
17 (1%) |
Dyspepsia |
30 (2%) |
9 (0.5%) |
Upper Abdominal Pain |
29 (2%) |
15 (1%) |
Musculoskeletal & Connective Tissue Disorders |
Arthralgia |
137 (8%) |
98 (6%) |
Back Pain |
91 (5%) |
58 (3%) |
Myalgia |
63 (4%) |
17 (1%) |
Bone Pain |
49 (3%) |
26 (2%) |
Muscle Spasm |
46 (3%) |
3 (0.2%) |
Nervous System Disorders |
Headache |
162 (10%) |
49 (3%) |
Paraesthesia |
29 (2%) |
11 (0.6%) |
Skin & Subcutaneous Tissue Disorders |
Rash |
70 (4%) |
10 (0.6%) |
Nail Disorders |
43 (2%) |
0 (0%) |
Pruritus |
40 (2%) |
10 (0.6%) |
General Disorders |
Pyrexia |
100 (6%) |
6 (0.4%) |
Edema Peripheral |
79 (5%) |
37 (2%) |
Chills |
85 (5%) |
0 (0%) |
Asthenia |
75 (4.5%) |
30 (2%) |
Influenza-like Illness |
40 (2%) |
3 (0.2%) |
Sudden Death |
1 (0.06%) |
0 (0%) |
Infections |
Nasopharyngitis |
135 (8%) |
43 (3%) |
UTI |
39 (3%) |
13 (0.8%) |
Immune System Disorders |
Hypersensitivity |
10 (0.6%) |
1 (0.06%) |
Autoimmune Thyroiditis |
4 (0.3%) |
0 (0%) |
a Median follow-up duration of 12.6 months in
the one-year trastuzumab treatment arm.
b The incidence of Grade 3 or higher adverse reactions was <1% in
both arms for each listed term
c Higher level grouping term |
In Study 3, a comparison of 3-weekly trastuzumab
treatment for two years versus one year was also performed. The rate of
asymptomatic cardiac dysfunction was increased in the 2-year trastuzumab
treatment arm (8.1% versus 4.6% in the one-year trastuzumab treatment arm).
More patients experienced at least one adverse reaction of Grade 3 or higher in
the 2-year trastuzumab treatment arm (20.4%) compared with the one-year
trastuzumab treatment arm (16.3%).
The safety data from Studies 1 and 2 were obtained from
3655 patients, of whom 2000 received trastuzumab; the median treatment duration
was 51 weeks. The median age was 49 years (range: 24-80); 84% of patients were
White, 7% Black, 4% Hispanic, and 3% Asian.
In Study 1, only Grade 3-5
adverse events, treatment-related Grade 2 events, and Grade 2-5 dyspnea were
collected during and for up to 3 months following protocol-specified treatment.
The following non-cardiac adverse reactions of Grade 2-5 occurred at an
incidence of at least 2% greater among patients receiving trastuzumab plus
chemotherapy as compared to chemotherapy alone: fatigue (29.5% vs. 22.4%),
infection (24.0% vs. 12.8%), hot flashes (17.1% vs. 15.0%), anemia (12.3% vs.
6.7%), dyspnea (11.8% vs. 4.6%), rash/desquamation (10.9% vs. 7.6%), leukopenia
(10.5% vs. 8.4%), neutropenia (6.4% vs. 4.3%), headache (6.2% vs. 3.8%), pain
(5.5% vs. 3.0%), edema (4.7% vs. 2.7%) and insomnia (4.3% vs. 1.5%). The
majority of these events were Grade 2 in severity.
In Study 2, data collection was
limited to the following investigator-attributed treatment-related adverse
reactions: NCI-CTC Grade 4 and 5 hematologic toxicities, Grade 3-5
non-hematologic toxicities, selected Grade 2-5 toxicities associated with
taxanes (myalgia, arthralgias, nail changes, motor neuropathy, sensory
neuropathy) and Grade 1-5 cardiac toxicities occurring during chemotherapy
and/or trastuzumab treatment. The following non-cardiac adverse reactions of
Grade 2-5 occurred at an incidence of at least 2% greater among patients
receiving trastuzumab plus chemotherapy as compared to chemotherapy alone:
arthralgia (12.2% vs. 9.1%), nail changes (11.5% vs.6.8%), dyspnea (2.4% vs.
0.2%), and diarrhea (2.2% vs. 0%). The majority of these events were Grade 2 in
severity.
Safety data from Study 4
reflect exposure to trastuzumab as part of an adjuvant treatment regimen from
2124 patients receiving at least one dose of study treatment [AC-TH: n = 1068;
TCH: n = 1056]. The overall median treatment duration was 54 weeks in both the
AC-TH and TCH arms. The median number of infusions was 26 in the AC-TH arm and
30 in the TCH arm, including weekly infusions during the chemotherapy phase and
every three week dosing in the monotherapy period. Among these patients, the
median age was 49 years (range 22 to 74 years). In Study 4, the toxicity
profile was similar to that reported in Studies 1, 2, and 3 with the exception
of a low incidence of CHF in the TCH arm.
Metastatic Breast Cancer
Studies
The data below reflect exposure
to trastuzumab in one randomized, open-label study, Study 5, of chemotherapy
with (n = 235) or without (n = 234) trastuzumab in patients with metastatic
breast cancer, and one single-arm study (Study 6; n = 222) in patients with
metastatic breast cancer. Data in Table 4 are based on Studies 5 and 6.
Among the 464 patients treated
in Study 5, the median age was 52 years (range: 25-77 years). Eighty-nine
percent were White, 5% Black, 1% Asian and 5% other racial/ethnic groups. All
patients received 4 mg/kg initial dose of trastuzumab followed by 2 mg/kg
weekly. The percentages of patients who received trastuzumab treatment for
≥ 6 months and ≥ 12 months were 58% and 9%, respectively.
Among the 352 patients treated
in single agent studies (213 patients from Study 6), the median age was 50 years
(range 28-86 years), 86% were White, 3% were Black, 3% were Asian, and 8% in
other racial/ethnic groups. Most of the patients received 4 mg/kg initial dose
of trastuzumab followed by 2 mg/kg weekly. The percentages of patients who
received trastuzumab treatment for ≥ 6 months and ≥ 12 months were
31% and 16%, respectively.
Table 4 : Per-Patient Incidence of Adverse
Reactions Occurring in ≥5% of Patients in Uncontrolled Studies or at
Increased Incidence in the Trastuzumab Arm (Studies 5 and 6)
|
Single Agenta
n = 352 |
Trastuzumab + Paclitaxel
n = 91 |
Paclitaxel Alone
n = 95 |
Trastuzumab + ACb
n = 143 |
ACb Alone
n = 135 |
Body as a Whole |
Pain |
47% |
61% |
62% |
57% |
42% |
Asthenia |
42% |
62% |
57% |
54% |
55% |
Fever |
36% |
49% |
23% |
56% |
34% |
Chills |
32% |
41% |
4% |
35% |
11% |
Headache |
26% |
36% |
28% |
44% |
31% |
Abdominal pain |
22% |
34% |
22% |
23% |
18% |
Back pain |
22% |
34% |
30% |
27% |
15% |
Infection |
20% |
47% |
27% |
47% |
31% |
Flu syndrome |
10% |
12% |
5% |
12% |
6% |
Accidental injury |
6% |
13% |
3% |
9% |
4% |
Allergic reaction |
3% |
8% |
2% |
4% |
2% |
Cardiovascular |
Tachycardia |
5% |
12% |
4% |
10% |
5% |
Congestive heart failure |
7% |
11% |
1% |
28% |
7% |
Digestive |
Nausea |
33% |
51% |
9% |
76% |
77% |
Diarrhea |
25% |
45% |
29% |
45% |
26% |
Vomiting |
23% |
37% |
28% |
53% |
49% |
Nausea and vomiting |
8% |
14% |
11% |
18% |
9% |
Anorexia |
14% |
24% |
16% |
31% |
26% |
Heme & Lymphatic |
Anemia |
4% |
14% |
9% |
36% |
26% |
Leukopenia |
3% |
24% |
17% |
52% |
34% |
Metabolic |
Peripheral edema |
10% |
22% |
20% |
20% |
17% |
Edema |
8% |
10% |
8% |
11% |
5% |
Musculoskeletal |
Bone pain |
7% |
24% |
18% |
7% |
7% |
Arthralgia |
6% |
37% |
21% |
8% |
9% |
Nervous |
Insomnia |
14% |
25% |
13% |
29% |
15% |
Dizziness |
13% |
22% |
24% |
24% |
18% |
Paresthesia |
9% |
48% |
39% |
17% |
11% |
Depression |
6% |
12% |
13% |
20% |
12% |
Peripheral neuritis |
2% |
23% |
16% |
2% |
2% |
Neuropathy |
1% |
13% |
5% |
4% |
4% |
Respiratory |
Cough increased |
26% |
41% |
22% |
43% |
29% |
Dyspnea |
22% |
27% |
26% |
42% |
25% |
Rhinitis |
14% |
22% |
5% |
22% |
16% |
Pharyngitis |
12% |
22% |
14% |
30% |
18% |
Sinusitis |
9% |
21% |
7% |
13% |
6% |
Skin |
Rash |
18% |
38% |
18% |
27% |
17% |
Herpes simplex |
2% |
12% |
3% |
7% |
9% |
Acne |
2% |
11% |
3% |
3% |
< 1% |
Urosenital |
Urinary tract infection |
5% |
18% |
14% |
13% |
7% |
a Data for trastuzumab single agent were from
4 studies, including 213 patients from Study 6.
b Anthracycline (doxorubicin or epirubicin) and cyclophosphamide. |
Metastatic Gastric Cancer
The data below are based on the exposure of 294 patients
to trastuzumab in combination with a fluoropyrimidine (capecitabine or 5-FU)
and cisplatin (Study 7). In the trastuzumab plus chemotherapy arm, the initial
dose of trastuzumab 8 mg/kg was administered on Day 1 (prior to chemotherapy)
followed by 6 mg/kg every 21 days until disease progression. Cisplatin was
administered at 80 mg/m² on Day 1 and the fluoropyrimidine was administered as
either capecitabine 1000 mg/m² orally twice a day on Days 1-14 or
5-fluorouracil 800 mg/m²/day as a continuous intravenous infusion Days 1
through 5.
Chemotherapy was administered
for six 21-day cycles. Median duration of trastuzumab treatment was 21 weeks;
median number of trastuzumab infusions administered was eight.
Table 5 : Study
7: Per Patient Incidence of Adverse Reactions of All Grades (Incidence ≥
5% between Arms) or Grade 3 /4 (Incidence > 1% between Arms) and Higher
Incidence in Trastuzumab Arm
Body System/Adverse Event |
Trastuzumab + FC
(N = 294)
N (%) |
FC
(N = 290)
N (%) |
All Grades |
Grades 3/4 |
All Grades |
Grades 3/4 |
Investigations |
Neutropenia |
230 (78) |
101 (34) |
212 (73) |
83 (29) |
Hypokalemia |
83 (28) |
28 (10) |
69 (24) |
16 (6) |
Anemia |
81 (28) |
36 (12) |
61 (21) |
30 (10) |
Thrombocytopenia |
47 (16) |
14 (5) |
33 (11) |
8 (3) |
Blood and Lymphatic System Disorders |
Febrile Neutropenia |
— |
15 (5) |
— |
8 (3) |
Gastrointestinal Disorders |
Diarrhea |
109 (37) |
27 (9) |
80 (28) |
11 (4) |
Stomatitis |
72 (24) |
2 (1) |
43 (15) |
6 (2) |
Dysphagia |
19 (6) |
7 (2) |
10 (3) |
1 (≤ 1) |
Body as a Whole |
Fatigue |
102 (35) |
12 (4) |
82 (28) |
7 (2) |
Fever |
54 (18) |
3 (1) |
36 (12) |
0 (0) |
Mucosal Inflammation |
37 (13) |
6 (2) |
18 (6) |
2 (1) |
Chills |
23 (8) |
1 (≤1) |
0 (0) |
0 (0) |
Metabolism and Nutrition Disorders |
Weight Decrease |
69 (23) |
6 (2) |
40 (14) |
7 (2) |
Infections and Infestations |
Upper Respiratory Tract Infections |
56 (19) |
0 (0) |
29 (10) |
0 (0) |
Nasopharyngitis |
37 (13) |
0 (0) |
17 (6) |
0 (0) |
Renal and Urinary Disorders |
Renal Failure and Impairment |
53 (18) |
8 (3) |
42 (15) |
5 (2) |
Nervous System Disorders |
Dysgeusia |
28 (10) |
0 (0) |
14 (5) |
0 (0) |
The following subsections provide additional detail
regarding adverse reactions observed in clinical trials of adjuvant breast
cancer, metastatic breast cancer, metastatic gastric cancer, or post-marketing
experience.
Cardiomyopathy
Serial measurement of cardiac
function (LVEF) was obtained in clinical trials in the adjuvant treatment of
breast cancer. In Study 3, the median duration of follow-up was12.6 months
(12.4 months in the observation arm; 12.6 months in the 1-year trastuzumab
arm); and in Studies 1 and 2, 7.9 years in the AC-T arm, 8.3 years in the AC-TH
arm. In Studies 1 and 2, 6% of all randomized patients with post-AC LVEF
evaluation were not permitted to initiate trastuzumab following completion of
AC chemotherapy due to cardiac dysfunction (LVEF < LLN or ≥ 16 point
decline in LVEF from baseline to end of AC).
Following initiation of
trastuzumab therapy, the incidence of new-onset dose-limiting myocardial
dysfunction was higher among patients receiving trastuzumab and paclitaxel as
compared to those receiving paclitaxel alone in Studies 1 and 2, and in
patients receiving one-year trastuzumab monotherapy compared to observation in
Study 3 (see Table 6, Figures 1 and 2). The per-patient incidence of new-onset
cardiac dysfunction, as measured by LVEF, remained similar when compared to the
analysis performed at a median follow-up of 2.0 years in the AC-TH arm. This
analysis also showed evidence of reversibility of left ventricular dysfunction,
with 64.5% of patients who experienced symptomatic CHF in the AC-TH group being
asymptomatic at latest follow-up, and 90.3% having full or partial LVEF
recovery.
Table 6a : Per-patient Incidence of New Onset
Myocardial Dysfunction (by LVEF) Studies 1, 2, 3 and 4
|
LVEF < 50% and Absolute Decrease from Baseline |
Absolute LVEF Decrease |
LVEF <50% |
≥10% decrease |
≥16% decrease |
<20% and ≥10% |
≥20% |
Studies 1 & 2b,c |
AC→TH |
23.1% |
18.5% |
11.2% |
37.9% |
8.9% |
(n= 1856) |
(428) |
(344) |
(208) |
(703) |
(166) |
AC→T |
11.7% |
7.0% |
3.0% |
22.1% |
3.4% |
(n= 1170) |
(137) |
(82) |
(35) |
(259) |
(40) |
Study 3d |
Trastuzumab |
8.6% |
7.0% |
3.8% |
22.4% |
3.5% |
(n=1678) |
(144) |
(118) |
(64) |
(376) |
(59) |
Observation |
2.7% |
2.0% |
1.2% |
11.9% |
1.2% |
(n=1708) |
(46) |
(35) |
(20) |
(204) |
(21) |
Studv4e |
TCH |
8.5% |
5.9% |
3.3% |
34.5% |
6.3% |
(n= 1056) |
(90) |
(62) |
(35) |
(364) |
(67) |
AC→TH |
17% |
13.3% |
9.8% |
44.3% |
13.2% |
(n = 1068) |
(182) |
(142) |
(105) |
(473) |
(141) |
AC→T |
9.5% |
6.6% |
3.3% |
34% |
5.5% |
(n = 1050) |
(100) |
(69) |
(35) |
(357) |
(58) |
a For Studies 1, 2 and 3, events are counted
from the beginning of trastuzumab treatment.
For Study 4, events are counted from the date of randomization.
b Studies 1 and 2 regimens: doxorubicin and cyclophosphamide
followed by paclitaxel (AC→T) or paclitaxel plus trastuzumab
(AC→TH).
c Median duration of follow-up for Studies 1 and 2 combined was 8.3
years in the AC→TH arm.
d Median follow-up duration of 12.6 months in the one-year
trastuzumab treatment arm.
e Study 4 regimens: doxorubicin and cyclophosphamide followed by
docetaxel (AC→T) or docetaxel plus trastuzumab (AC→TH); docetaxel
and carboplatin plus trastuzumab(TCH). |
Figure 1 : Studies 1 and 2: Cumulative Incidence of
Time to First LVEF Decline of ≥ 10 Percentage Points from Baseline and to
Below 50% with Death as a Competing Risk Event
Time 0 is initiation of
paclitaxel or trastuzumab + paclitaxel therapy.
Figure 2 : Study 3: Cumulative Incidence of Time to First LVEF Decline
of ≥ 10 Percentage Points from Baseline and to Below 50% with Death as a
Competing Risk Event
Time 0 is the date of
randomization.
Figure 3 : Study 4: Cumulative Incidence of
Time to First LVEF Decline of ≥10 Percentage Points from Baseline and to
Below 50% with Death as a Competing Risk Event
Time 0 is the date of
randomization.
The incidence of treatment
emergent congestive heart failure among patients in the metastatic breast
cancer trials was classified for severity using the New York Heart Association
classification system (I-IV, where IV is the most severe level of cardiac failure)
(see Table 2). In the metastatic breast cancer trials, the probability of
cardiac dysfunction was highest in patients who received trastuzumab
concurrently with anthracyclines.
In Study 7, 5.0% of patients in
the trastuzumab plus chemotherapy arm compared to 1.1% of patients in the
chemotherapy alone arm had LVEF value below 50% with a ≥ 10% absolute
decrease in LVEF from pretreatment values.
Infusion Reactions
During the first infusion with
trastuzumab, the symptoms most commonly reported were chills and fever,
occurring in approximately 40% of patients in clinical trials. Symptoms were
treated with acetaminophen, diphenhydramine, and meperidine (with or without
reduction in the rate of trastuzumab infusion); permanent discontinuation of
trastuzumab for infusion reactions was required in < 1% of patients. Other
signs and/or symptoms may include nausea, vomiting, pain (in some cases at
tumor sites), rigors, headache, dizziness, dyspnea, hypotension, elevated blood
pressure, rash, and asthenia. Infusion reactions occurred in 21% and 35% of
patients, and were severe in 1.4% and 9% of patients, on second or subsequent
trastuzumab infusions administered as monotherapy or in combination with
chemotherapy, respectively. In the post-marketing setting, severe infusion
reactions, including hypersensitivity, anaphylaxis, and angioedema have been
reported.
Anemia
In randomized controlled
clinical trials, the overall incidence of anemia (30% vs. 21% [Study 5]), of
selected NCI-CTC Grade 2-5 anemia (12.3% vs. 6.7% [Study 1]), and of anemia
requiring transfusions (0.1% vs. 0 patients [Study 2]) were increased in
patients receiving trastuzumab and chemotherapy compared with those receiving
chemotherapy alone. Following the administration of trastuzumab as a single
agent (Study 6), the incidence of NCI-CTC Grade 3 anemia was < 1%. In Study
7 (metastatic gastric cancer), on the trastuzumab containing arm as compared to
the chemotherapy alone arm, the overall incidence of anemia was 28% compared to
21% and of NCI-CTC Grade 3/4 anemia was 12.2% compared to 10.3%.
Neutropenia
In randomized controlled
clinical trials in the adjuvant setting, the incidence of selected NCI-CTC Grade
4-5 neutropenia (1.7% vs. 0.8% [Study 2]) and of selected Grade 2-5 neutropenia
(6.4% vs. 4.3% [Study 1]) were increased in patients receiving trastuzumab and
chemotherapy compared with those receiving chemotherapy alone. In a randomized,
controlled trial in patients with metastatic breast cancer, the incidences of
NCI-CTC Grade 3/4 neutropenia (32% vs. 22%) and of febrile neutropenia (23% vs.
17%) were also increased in patients randomized to trastuzumab in combination
with myelosuppressive chemotherapy as compared to chemotherapy alone. In Study
7 (metastatic gastric cancer) on the trastuzumab containing arm as compared to
the chemotherapy alone arm, the incidence of NCI-CTC Grade 3/4 neutropenia was
36.8% compared to 28.9%; febrile neutropenia 5.1% compared to 2.8%.
Infection
The overall incidences of
infection (46% vs. 30% [Study 5]), of selected NCI-CTC Grade 2-5
infection/febrile neutropenia (24.3% vs. 13.4% [Study 1]) and of selected Grade
3-5 infection/febrile neutropenia (2.9% vs. 1.4%) [Study 2]) were higher in
patients receiving trastuzumab and chemotherapy compared with those receiving
chemotherapy alone. The most common site of infections in the adjuvant setting
involved the upper respiratory tract, skin, and urinary tract.
In Study 4, the overall
incidence of infection was higher with the addition of trastuzumab to AC-T but
not to TCH [44% (AC-TH), 37% (TCH), 38% (AC-T)]. The incidences of NCI-CTC
Grade 3-4 infection were similar [25% (AC-TH), 21% (TCH), 23% (AC-T)] across
the three arms.
In a randomized, controlled
trial in treatment of metastatic breast cancer, the reported incidence of
febrile neutropenia was higher (23% vs. 17%) in patients receiving trastuzumab
in combination with myelosuppressive chemotherapy as compared to chemotherapy
alone.
Pulmonary Toxicity
Adjuvant Breast Cancer
Among women receiving adjuvant therapy for breast cancer,
the incidence of selected NCI-CTC Grade 2-5 pulmonary toxicity (14.3% vs. 5.4%
[Study 1]) and of selected NCI-CTC Grade 3-5 pulmonary toxicity and spontaneous
reported Grade 2 dyspnea (3.4% vs. 0.9% [Study 2]) was higher in patients
receiving trastuzumab and chemotherapy compared with chemotherapy alone. The
most common pulmonary toxicity was dyspnea (NCI-CTC Grade 2-5: 11.8% vs. 4.6%
[Study 1]; NCI-CTC Grade 2-5: 2.4% vs. 0.2% [Study 2]).
Pneumonitis/pulmonary infiltrates occurred in 0.7% of
patients receiving trastuzumab compared with 0.3% of those receiving
chemotherapy alone. Fatal respiratory failure occurred in 3 patients receiving
trastuzumab, one as a component of multi-organ system failure, as compared to 1
patient receiving chemotherapy alone.
In Study 3, there were 4 cases of interstitial
pneumonitis in the one-year trastuzumab treatment arm compared to none in the
observation arm at a median follow-up duration of 12.6 months.
Metastatic Breast Cancer
Among women receiving trastuzumab for treatment of
metastatic breast cancer, the incidence of pulmonary toxicity was also
increased. Pulmonary adverse events have been reported in the post-marketing
experience as part of the symptom complex of infusion reactions. Pulmonary
events include bronchospasm, hypoxia, dyspnea, pulmonary infiltrates, pleural
effusions, non-cardiogenic pulmonary edema, and acute respiratory distress
syndrome. For a detailed description, [see WARNINGS
AND PRECAUTIONS].
Thrombosis/Embolism
In 4 randomized, controlled clinical trials, the
incidence of thrombotic adverse events was higher in patients receiving
trastuzumab and chemotherapy compared to chemotherapy alone in three studies
(2.6% vs. 1.5% [Study 1], 2.5% and 3.7% vs. 2.2% [Study 4] and 2.1% vs. 0%
[Study 5]).
Diarrhea
Among women receiving adjuvant therapy for breast cancer,
the incidence of NCI-CTC Grade 2-5 diarrhea (6.7% vs. 5.4% [Study 1]) and of
NCI-CTC Grade 3-5 diarrhea (2.2% vs. 0% [Study 2]), and of Grade 1-4 diarrhea
(7% vs. 1% [Study 3; one-year trastuzumab treatment at 12.6 months median
duration of follow-up]) were higher in patients receiving trastuzumab as
compared to controls. In Study 4, the incidence of Grade 3-4 diarrhea was
higher [5.7% AC-TH, 5.5% TCH vs. 3.0% AC-T] and of Grade 1-4 was higher [51%
AC-TH, 63% TCH vs. 43% AC-T] among women receiving trastuzumab. Of patients
receiving trastuzumab as a single agent for the treatment of metastatic breast
cancer, 25% experienced diarrhea. An increased incidence of diarrhea was
observed in patients receiving trastuzumab in combination with chemotherapy for
treatment of metastatic breast cancer.
Renal Toxicity
In Study 7 (metastatic gastric cancer) on the
trastuzumab-containing arm as compared to the chemotherapy alone arm the
incidence of renal impairment was 18% compared to 14.5%. Severe (Grade 3/4)
renal failure was 2.7% on the trastuzumab-containing arm compared to 1.7% on
the chemotherapy only arm.
Treatment discontinuation for renal insufficiency/failure
was 2% on the trastuzumab-containing arm and 0.3% on the chemotherapy only arm.
In the post-marketing setting, rare cases of nephrotic
syndrome with pathologic evidence of glomerulopathy have been reported. The
time to onset ranged from 4 months to approximately 18 months from initiation
of trastuzumab therapy. Pathologic findings included membranous
glomerulonephritis, focal glomerulosclerosis, and fibrillary
glomerulonephritis. Complications included volume overload and congestive heart
failure.
Immunogenicity
As with all therapeutic proteins, there is a potential
for immunogenicity.
The detection of antibody formation is highly dependent
on the sensitivity and the 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 in the
studies described below with the incidence of antibodies in other studies or to
other trastuzumab products may be misleading.
Among 903 women with metastatic breast cancer, human
anti-human antibody (HAHA) to trastuzumab was detected in one patient using an
enzyme-linked immunosorbent assay (ELISA). This patient did not experience an
allergic reaction. Samples for assessment of HAHA were not collected in studies
of adjuvant breast cancer.
Post-Marketing Experience
The following adverse reactions have been identified
during post-approval use of trastuzumab. Because these reactions are reported
voluntarily from a population of uncertain size, it is not always possible to
reliably estimate their frequency or establish a causal relationship to drug
exposure.
- Infusion reactions [see WARNINGS
AND PRECAUTIONS]
- Oligohydramnios or oligohydramnios sequence, including
pulmonary hypoplasia, skeletal abnormalities, and neonatal death [see WARNINGS AND PRECAUTIONS]
- Glomerulopathy.
- Immune thrombocytopenia
- Tumor lysis syndrome (TLS): Cases of possible TLS have
been reported in patients treated with trastuzumab. Patients with significant
tumor burden (e.g. bulky metastases) may be at a higher risk. Patients could
present with hyperuricemia, hyperphosphatemia, and acute renal failure which
may represent possible TLS. Providers should consider additional monitoring
and/or treatment as clinically indicated.
DRUG INTERACTIONS
Patients who receive anthracycline after stopping
trastuzumab products may be at increased risk of cardiac dysfunction because of
trastuzumab's long washout period based on population PK analysis [see CLINICAL
PHARMACOLOGY]. If possible, physicians should avoid anthracycline-based
therapy for up to 7 months after stopping trastuzumab products. If
anthracyclines are used, the patient's cardiac function should be monitored
carefully.