WARNINGS
Included as part of the "PRECAUTIONS" Section
PRECAUTIONS
Hepatotoxicity
Hepatotoxicity, predominantly in the form of asymptomatic, transient increases in the
concentrations of serum transaminases, has been observed in clinical trials with KADCYLA [see ADVERSE REACTIONS]. Serious hepatobiliary disorders, including at least two fatal cases of
severe drug-induced liver injury and associated hepatic encephalopathy, have been reported in
clinical trials with KADCYLA. Some of the observed cases may have been confounded by
comorbidities and/or concomitant medications with known hepatotoxic potential.
Monitor serum transaminases and bilirubin prior to initiation of KADCYLA treatment and prior
to each KADCYLA dose. Patients with known active hepatitis B virus or hepatitis C virus were
excluded from Study 1 [see Clinical Studies]. Reduce the dose or discontinue
KADCYLA as appropriate in cases of increased serum transaminases and/or total bilirubin [see DOSAGE AND ADMINISTRATION]. Permanently discontinue KADCYLA treatment in patients
with serum transaminases > 3 x ULN and concomitant total bilirubin > 2 x ULN. KADCYLA
has not been studied in patients with serum transaminases > 2.5 x ULN or bilirubin > 1.5 x ULN
prior to the initiation of treatment.
In clinical trials of KADCYLA, cases of nodular regenerative hyperplasia (NRH) of the liver
have been identified from liver biopsies (3 cases out of 884 treated patients, one of which was
fatal). Two of these three cases of NRH were observed in the randomized trial (Study 1) [see ADVERSE REACTIONS]. NRH is a rare liver condition characterized by widespread benign
transformation of hepatic parenchyma into small regenerative nodules; NRH may lead to noncirrhotic
portal hypertension. The diagnosis of NRH can be confirmed only by histopathology.
NRH should be considered in all patients with clinical symptoms of portal hypertension and/or
cirrhosis-like pattern seen on the computed tomography (CT) scan of the liver but with normal
transaminases and no other manifestations of cirrhosis. Upon diagnosis of NRH, KADCYLA
treatment must be permanently discontinued.
Left Ventricular Dysfunction
Patients treated with KADCYLA are at increased risk of developing left ventricular dysfunction.
A decrease of LVEF to < 40% has been observed in patients treated with KADCYLA. In the
randomized trial (Study 1), left ventricular dysfunction occurred in 1.8% of patients in the
KADCYLA-treated group and 3.3% of patients in the lapatinib plus capecitabine-treated group
[see ADVERSE REACTIONS].
Assess LVEF prior to initiation of KADCYLA and at regular intervals (e.g. every three months)
during treatment to ensure the LVEF is within the institution’s normal limits. Treatment with
KADCYLA has not been studied in patients with LVEF < 50% prior to initiation of treatment.
If, at routine monitoring, LVEF is < 40%, or is 40% to 45% with a 10% or greater absolute
decrease below the pretreatment value, withhold KADCYLA and repeat LVEF assessment
within approximately 3 weeks. Permanently discontinue KADCYLA if the LVEF has not
improved or has declined further [see DOSAGE AND ADMINISTRATION]. Patients with a history
of symptomatic congestive heart failure (CHF), serious cardiac arrhythmia, or history of
myocardial infarction or unstable angina within 6 months were excluded from Study 1 [see Clinical Studies].
Embryo-Fetal Toxicity
KADCYLA can cause fetal harm when administered to a pregnant woman. Cases of
oligohydramnios, and oligohydramnios sequence manifesting as pulmonary hypoplasia, skeletal
abnormalities and neonatal death were observed in the postmarketing setting in patients treated
with trastuzumab, the antibody component of KADCYLA. DM1, the cytotoxic component of
KADCYLA, can cause embryo-fetal toxicity based on its mechanism of action.
Verify the pregnancy status of females of reproductive potential prior to the initiation of
KADCYLA. Advise pregnant women and females of reproductive potential that exposure to
KADCYLA during pregnancy or within 7 months prior to conception can result in fetal harm.
Advise females of reproductive potential to use effective contraception during treatment and for
7 months following the last dose of KADCYLA [see Use In Specific Populations].
Pulmonary Toxicity
Cases of interstitial lung disease (ILD), including pneumonitis, some leading to acute respiratory
distress syndrome or fatal outcome have been reported in clinical trials with KADCYLA.
Pneumonitis at an incidence of 0.8% (7 out of 884 treated patients) has been reported, with one
case of grade 3 pneumonitis. Signs and symptoms include dyspnea, cough, fatigue, and
pulmonary infiltrates. These events may or may not occur as sequelae of infusion reactions. In
the randomized trial (Study 1), the overall frequency of pneumonitis was 1.2% [see ADVERSE REACTIONS].
Permanently discontinue treatment with KADCYLA in patients diagnosed with ILD or
pneumonitis.
Patients with dyspnea at rest due to complications of advanced malignancy and co-morbidities
may be at increased risk of pulmonary toxicity.
Infusion-Related Reactions, Hypersensitivity Reactions
Treatment with KADCYLA has not been studied in patients who had trastuzumab permanently
discontinued due to infusion-related reactions (IRR) and/or hypersensitivity; treatment with
KADCYLA is not recommended for these patients.
Infusion-related reactions, characterized by one or more of the following symptoms − flushing,
chills, pyrexia, dyspnea, hypotension, wheezing, bronchospasm, and tachycardia have been
reported in clinical trials of KADCYLA. In the randomized trial (Study 1), the overall frequency
of IRRs in patients treated with KADCYLA was 1.4% [see ADVERSE REACTIONS]. In most
patients, these reactions resolved over the course of several hours to a day after the infusion was
terminated. KADCYLA treatment should be interrupted in patients with severe IRR.
KADCYLA treatment should be permanently discontinued in the event of a life-threatening IRR
[see DOSAGE AND ADMINISTRATION]. Patients should be observed closely for IRR reactions,
especially during the first infusion.
One case of a serious, allergic/anaphylactic-like reaction has been observed in clinical trials of
single-agent KADCYLA. Medications to treat such reactions, as well as emergency equipment,
should be available for immediate use.
Hemorrhage
Cases of hemorrhagic events, including central nervous system, respiratory, and gastrointestinal
hemorrhage, have been reported in clinical trials with Kadcyla. Some of these bleeding events
resulted in fatal outcomes. In the randomized trial (Study 1), the overall frequency of
hemorrhage was 32.2% in the KADCYLA-treated group and 16.4% in the lapatinib plus
capecitabine-treated group. The incidence of ≥ Grade 3 hemorrhage was 1.8% in the
KADCYLA-treated group and 0.8% in the lapatinib plus capecitabine-treated group [see ADVERSE REACTIONS]. Although, in some of the observed cases the patients were also receiving anticoagulation
therapy, antiplatelet therapy, or had thrombocytopenia, in others there were no
known additional risk factors. Use caution with these agents and consider additional monitoring
when concomitant use is medically necessary.
Thrombocytopenia
Thrombocytopenia, or decreased platelet count, was reported in clinical trials of KADCYLA
(103 of 884 treated patients with ≥ Grade 3; 283 of 884 treated patients with any Grade). The
majority of these patients had Grade 1 or 2 events (< LLN to ≥ 50,000/mm3) with the nadir
occurring by day 8 and generally improving to Grade 0 or 1 (≥ 75,000 /mm3) by the next
scheduled dose. In clinical trials of KADCYLA, the incidence and severity of thrombocytopenia
were higher in Asian patients.
In the randomized trial (Study 1), the overall frequency of thrombocytopenia was 31.2% in the
KADCYLA-treated group and 3.3% in the lapatinib plus capecitabine-treated group [see ADVERSE REACTIONS]. The incidence of ≥ Grade 3 thrombocytopenia was 14.5% in the KADCYLAtreated
group and 0.4% in the lapatinib plus capecitabine-treated group. In Asian patients, the
incidence of > Grade 3 thrombocytopenia was 45.1% in the KADCYLA-treated group and 1.3%
in the lapatinib plus capecitabine-treated group.
Monitor platelet counts prior to initiation of KADCYLA and prior to each KADCYLA dose [see DOSAGE AND ADMINISTRATION]. KADCYLA has not been studied in patients with platelet
counts <100,000/mm3 prior to initiation of treatment. In the event of decreased platelet count to
Grade 3 or greater (< 50,000/mm3) do not administer KADCYLA until platelet counts recover to
Grade 1 (≥ 75,000/mm3) [see DOSAGE AND ADMINISTRATION]. Patients with
thrombocytopenia (< 100,000/mm3) and patients on anti-coagulant treatment should be closely
monitored during treatment with KADCYLA.
Neurotoxicity
Peripheral neuropathy, mainly as Grade 1 and predominantly sensory, was reported in clinical
trials of KADCYLA (14 of 884 treated patients with ≥ Grade 3; 196 of 884 treated patients with
any Grade). In the randomized trial (Study 1), the overall frequency of peripheral neuropathy
was 21.2% in the KADCYLA-treated group and 13.5% in the lapatinib plus capecitabine-treated
group [see ADVERSE REACTIONS]. The incidence of ≥ Grade 3 peripheral neuropathy was
2.2% in the KADCYLA-treated group and 0.2% in the lapatinib plus capecitabine-treated group.
KADCYLA should be temporarily discontinued in patients experiencing Grade 3 or 4 peripheral
neuropathy until resolution to ≤ Grade 2. Patients should be clinically monitored on an ongoing
basis for signs or symptoms of neurotoxicity [see Nonclinical Toxicology].
Her2 Testing
Detection of HER2 protein overexpression or gene amplification is necessary for selection of
patients appropriate for KADCYLA therapy because these are the only patients studied for
whom benefit has been shown [see INDICATIONS , Clinical Studies]. In the
randomized study (Study 1), patients with breast cancer were required to have evidence of HER2
overexpression defined as 3+ IHC by Dako Herceptest™ or evidence of overexpression defined
as FISH amplification ratio ≥ 2.0 by Dako HER2 FISH PharmDx™ test kit. Only limited data
were available for patients whose breast cancer was positive by FISH and 0 or 1+ by IHC.
Assessment of HER2 status should be performed by laboratories with demonstrated proficiency
in the specific technology being utilized. Improper assay performance, including use of suboptimally
fixed tissue, failure to utilize specified reagents, deviation from specific assay
instructions, and failure to include appropriate controls for assay validation, can lead to
unreliable results.
Extravasation
In KADCYLA clinical studies, reactions secondary to extravasation have been observed. These
reactions, observed more frequently within 24 hours of infusion, were usually mild and
comprised erythema, tenderness, skin irritation, pain, or swelling at the infusion site. Specific
treatment for KADCYLA extravasation is unknown. The infusion site should be closely
monitored for possible subcutaneous infiltration during drug administration.
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Carcinogenicity studies have not been conducted with ado-trastuzumab emtansine.
DM1 was aneugenic or clastogenic in an in vivo single-dose rat bone marrow micronucleus assay
at exposures that were comparable to mean maximum concentrations of DM1 measured in
humans administered KADCYLA. DM1 was not mutagenic in an in vitro bacterial reverse
mutation (Ames) assay.
Based on results from animal toxicity studies, KADCYLA may impair fertility in humans. In a
single-dose toxicity study of ado-trastuzumab emtansine in rats, degeneration of seminiferous
tubules with hemorrhage in the testes associated with increased weights of testes and
epididymides at a severely toxic dose level (60 mg/kg; about 4 times the clinical exposure based
on AUC) were observed. The same dose in female rats resulted in signs of hemorrhage and
necrosis of the corpus luteum in ovaries. In monkeys dosed with ado-trastuzumab emtansine
once every three weeks for 12 weeks (four doses), at up to 30 mg/kg (about 7 times the clinical
exposure based on AUC), there were decreases in the weights of epididymides, prostate, testes,
seminal vesicles and uterus, although the interpretation of these effects is unclear due to the
varied sexual maturity of enrolled animals.
Use In Specific Populations
Pregnancy
Pregnancy Exposure Registry And Pregnancy Pharmacovigilance Program
There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to
KADCYLA during pregnancy. Encourage women who receive KADCYLA during pregnancy or
within 7 months prior to conception, to enroll in the MotHER Pregnancy Registry by contacting
1-800-690-6720 or visiting http://www.motherpregnancyregistry.com/.
In addition, there is a pregnancy pharmacovigilance program for KADCYLA. If KADCYLA is
administered during pregnancy, or if a patient becomes pregnant while receiving KADCYLA or
within 7 months following the last dose of KADCYLA, health care providers and patients should
immediately report KADCYLA exposure to Genentech at 1-888-835-2555.
Risk Summary
KADCYLA can cause fetal harm when administered to a pregnant woman. There are no
available data on the use of KADCYLA in pregnant women. Cases of oligohydramnios and
oligohydramnios sequence manifesting as pulmonary hypoplasia, skeletal abnormalities, and
neonatal death were observed in the postmarketing setting in patients treated with trastuzumab,
the antibody component of KADCYLA [see Data]. Based on its mechanism of action, the DM1
component of KADCYLA can also cause embryo-fetal harm when administered to a pregnant
woman [see Data]. Apprise the patient of the potential risks to a fetus. There are clinical
considerations if KADCYLA is used in a pregnant woman, or if a patient becomes pregnant
within 7 months following the last dose of KADCYLA [see Clinical Considerations].
The estimated background risk of major birth defects and miscarriage for the indicated
population is unknown. In the U.S. general population, the estimated background risk of major
birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%,
respectively.
Clinical Considerations
Fetal/Neonatal Adverse Reactions
Monitor women who received KADCYLA during pregnancy or within 7 months prior to
conception for oligohydramnios. If oligohydramnios occurs, perform fetal testing that is
appropriate for gestational age and consistent with community standards of care.
Data
Human Data
There are no available data on the use of KADCYLA in pregnant women. In the post-marketing
setting, cases of oligohydramnios, and of oligohydramnios sequence, manifesting in the fetus as
pulmonary hypoplasia, skeletal abnormalities and neonatal death were observed after treatment
with trastuzumab during pregnancy. These case reports described oligohydramnios in pregnant
women who received trastuzumab either alone or in combination with chemotherapy. In some
case reports, amniotic fluid index increased after trastuzumab was stopped. In one case,
trastuzumab therapy resumed after amniotic index improved, and oligohydramnios recurred.
Animal Data
There were no reproductive and developmental toxicology studies conducted with adotrastuzumab
emtansine. DM1, the cytotoxic component of KADCYLA, disrupts microtubule
function. DM1 is toxic to rapidly dividing cells in animals and is genotoxic, suggesting it has the
potential to cause embryotoxicity and teratogenicity. In studies where trastuzumab was
administered to pregnant cynomolgus monkeys during the period of organogenesis at doses up to
25 mg/kg given twice weekly (about 7 times the clinical dose), trastuzumab crossed the placental
barrier during the early (Gestation Days 20 to 50) and late (Gestation Days 120 to 150) phases of
gestation. The resulting concentrations of trastuzumab in fetal serum and amniotic fluid were
approximately 33% and 25%, respectively, of those present in the maternal serum but were not
associated with adverse developmental effects.
Lactation
Risk Summary
There is no information regarding the presence of ado-trastuzumab emtansine in human milk, the
effects on the breastfed infant, or the effects on milk production. DM1, the cytotoxic component
of KADCYLA, may cause serious adverse reactions in breastfed infants based on its mechanism
of action [see Data]. Advise women not to breastfeed during treatment and for 7 months
following the last dose of KADCYLA.
Data
There were no animal lactation studies conducted with ado-trastuzumab emtansine or the
cytotoxic component of KADCYLA (DM1). In lactating cynomolgus monkeys, trastuzumab was
present in breast milk at about 0.3% of maternal serum concentrations after pre- (beginning
Gestation Day 120) and post-partum (through Post-partum Day 28) doses of 25 mg/kg
administered twice weekly (about 7 times the clinical dose of KADCYLA). Infant monkeys with
detectable serum levels of trastuzumab did not exhibit any adverse effects on growth or
development from birth to 1 month of age.
Females And Males Of Reproductive Potential
Pregnancy Testing
Verify the pregnancy status of females of reproductive potential prior to the initiation of
KADCYLA.
Contraception
Females
KADCYLA can cause embryo-fetal harm when administered during pregnancy. Advise females
of reproductive potential to use effective contraception during treatment and for 7 months
following the last dose of KADCYLA [see Pregnancy].
Males
Because of the potential for genotoxicity, advise male patients with female partners of
reproductive potential to use effective contraception during treatment with KADCYLA and for 4
months following the last dose.
Infertility
Based on results from animal toxicity studies, KADCYLA may impair fertility in females and
males of reproductive potential. It is not known if the effects are reversible [see Nonclinical Toxicology].
Pediatric Use
Safety and effectiveness of KADCYLA have not been established in pediatric patients.
Geriatric Use
Of 495 patients who were randomized to KADCYLA in the randomized trial (Study 1) [see Clinical Studies], 65 patients (13%) were ≥ 65 years of age and 11 patients (2%) were ≥
75 years of age. In patients ≥ 65 years old (n=138 across both treatment arms) the hazard ratios
for progression-free survival (PFS) and Overall Survival (OS) were 1.06 (95% CI: 0.68, 1.66)
and 1.05 (95% CI: 0.58, 1.91), respectively.
Population pharmacokinetic analysis indicates that age does not have a clinically meaningful
effect on the pharmacokinetics of ado-trastuzumab emtansine [see CLINICAL PHARMACOLOGY].
Renal Impairment
No dedicated renal impairment trial for KADCYLA has been conducted. Based on the
population pharmacokinetics, as well as analysis of Grade 3 or greater adverse drug reactions
and dose modifications, dose adjustments of KADCYLA are not needed in patients with mild
(creatinine clearance [CLcr] 60 to 89 mL/min) or moderate (CLcr 30 to 59 mL/min) renal
impairment. No dose adjustment can be recommended for patients with severe renal impairment
(CLcr less than 30 mL/min) because of the limited data available [see CLINICAL PHARMACOLOGY].
Hepatic Impairment
No adjustment to the starting dose is required for patients with mild or moderate hepatic
impairment [see CLINICAL PHARMACOLOGY]. KADCYLA was not studied in patients with
severe hepatic impairment. Closely monitor patients with hepatic impairment due to known
hepatotoxicity observed with KADCYLA [see WARNINGS AND PRECAUTIONS, Hepatotoxicity].