WARNINGS
Included as part of the PRECAUTIONS section.
PRECAUTIONS
Depression And Suicidality In Patients With Huntington’s
Disease
Patients with Huntington’s disease are at increased risk
for depression, and suicidal ideation or behaviors (suicidality). AUSTEDO may
increase the risk for suicidality in patients with Huntington’s disease.
In a 12-week, double-blind, placebo-controlled trial,
suicidal ideation was reported by 2% of patients treated with AUSTEDO, compared
to no patients on placebo; no suicide attempts and no completed suicides were
reported. Depression was reported by 4% of patients treated with AUSTEDO.
When considering the use of AUSTEDO, the risk of
suicidality should be balanced against the need for treatment of chorea. All
patients treated with AUSTEDO should be observed for new or worsening
depression or suicidality. If depression or suicidality does not resolve,
consider discontinuing treatment with AUSTEDO.
Patients, their caregivers, and families should be
informed of the risks of depression, worsening depression, and suicidality
associated with AUSTEDO, and should be instructed to report behaviors of
concern promptly to the treating physician. Patients with Huntington’s disease
who express suicidal ideation should be evaluated immediately.
Clinical Worsening And Adverse Events In Patients With Huntington’s
Disease
Huntington’s disease is a progressive disorder
characterized by changes in mood, cognition, chorea, rigidity, and functional
capacity over time. VMAT2 inhibitors, including AUSTEDO, may cause a worsening
in mood, cognition, rigidity, and functional capacity.
Prescribers should periodically re-evaluate the need for
AUSTEDO in their patients by assessing the effect on chorea and possible
adverse effects, including sedation/somnolence, depression and suicidality,
parkinsonism, akathisia, restlessness, and cognitive decline. It may be
difficult to distinguish between adverse reactions and progression of the
underlying disease; decreasing the dose or stopping the drug may help the
clinician to distinguish between the two possibilities. In some patients, the
underlying chorea itself may improve over time, decreasing the need for
AUSTEDO.
QTc Prolongation
Tetrabenazine, a closely related VMAT2 inhibitor, causes
an increase (about 8 msec) in the corrected QT (QTc) interval.
A clinically relevant QT prolongation may occur in some
patients treated with AUSTEDO who are CYP2D6 poor metabolizers or are
co-administered a strong CYP2D6 inhibitor [see CLINICAL PHARMACOLOGY].
For patients who are CYP2D6 poor metabolizers or are
taking a strong CYP2D6 inhibitor, dose reduction may be necessary [see
DOSAGE AND ADMINISTRATION]. The use of AUSTEDO in combination with other
drugs that are known to prolong QTc may result in clinically significant QT
prolongations [see DRUG INTERACTIONS].
For patients requiring AUSTEDO doses greater than 24 mg
per day who are using AUSTEDO with other drugs known to prolong QTc, assess the
QTc interval before and after increasing the dose of AUSTEDO or other
medications that are known to prolong QTc.
AUSTEDO should also be avoided in patients with
congenital long QT syndrome and in patients with a history of cardiac
arrhythmias. Certain circumstances may increase the risk of the occurrence of
torsade de pointes and/or sudden death in association with the use of drugs
that prolong the QTc interval, including (1) bradycardia; (2) hypokalemia or hypomagnesemia;
(3) concomitant use of other drugs that prolong the QTc interval; and (4)
presence of congenital prolongation of the QT interval.
Neuroleptic Malignant Syndrome (NMS)
A potentially fatal symptom complex sometimes referred to
as Neuroleptic Malignant Syndrome (NMS) has been reported in association with
drugs that reduce dopaminergic transmission. While NMS has not been observed in
patients receiving AUSTEDO, it has been observed in patients receiving
tetrabenazine (a closely related VMAT2 inhibitor). Clinicians should be alerted
to the signs and symptoms associated with NMS. Clinical manifestations of NMS
are hyperpyrexia, muscle rigidity, altered mental status, and evidence of
autonomic instability (irregular pulse or blood pressure, tachycardia,
diaphoresis, and cardiac dysrhythmia). Additional signs may include elevated
creatinine phosphokinase, myoglobinuria, rhabdomyolysis, and acute renal
failure. The diagnosis of NMS can be complicated; other serious medical illness
(e.g., pneumonia, systemic infection) and untreated or inadequately treated
extrapyramidal disorders can present with similar signs and symptoms. Other
important considerations in the differential diagnosis include central
anticholinergic toxicity, heat stroke, drug fever, and primary central nervous
system pathology.
The management of NMS should include (1) immediate
discontinuation of AUSTEDO; (2) intensive symptomatic treatment and medical
monitoring; and (3) treatment of any concomitant serious medical problems for
which specific treatments are available. There is no general agreement about
specific pharmacological treatment regimens for NMS.
Recurrence of NMS has been reported with resumption of
drug therapy. If treatment with AUSTEDO is needed after recovery from NMS,
patients should be monitored for signs of recurrence.
Akathisia, Agitation, And Restlessness
AUSTEDO may increase the risk of akathisia, agitation,
and restlessness in patients with Huntington’s disease and tardive dyskinesia.
In a 12-week, double-blind, placebo-controlled trial in
Huntington’s disease patients, akathisia, agitation, or restlessness was
reported by 4% of patients treated with AUSTEDO, compared to 2% of patients on
placebo; in patients with tardive dyskinesia, 2% of patients treated with
AUSTEDO and 1% of patients on placebo experienced these events.
Patients receiving AUSTEDO should be monitored for signs
and symptoms of restlessness and agitation, as these may be indicators of
developing akathisia. If a patient develops akathisia during treatment with
AUSTEDO, the AUSTEDO dose should be reduced; some patients may require
discontinuation of therapy.
Parkinsonism In Patients With Huntington’s Disease
AUSTEDO may cause parkinsonism in patients with Huntington’s
disease.
Because rigidity can develop as part of the underlying
disease process in Huntington’s disease, it may be difficult to distinguish
between this potential drug-induced adverse reaction and progression of the
underlying disease process. Drug-induced parkinsonism has the potential to
cause more functional disability than untreated chorea for some patients with
Huntington’s disease. If a patient develops parkinsonism during treatment with
AUSTEDO, the AUSTEDO dose should be reduced; some patients may require
discontinuation of therapy.
Sedation And Somnolence
Sedation is a common dose-limiting adverse reaction of
AUSTEDO. In a 12-week, double-blind, placebo-controlled trial examining
patients with Huntington’s disease, 11% of AUSTEDO-treated patients reported
somnolence compared with 4% of patients on placebo and 9% of AUSTEDO-treated
patients reported fatigue compared with 4% of placebo-treated patients.
Patients should not perform activities requiring mental
alertness to maintain the safety of themselves or others, such as operating a
motor vehicle or operating hazardous machinery, until they are on a maintenance
dose of AUSTEDO and know how the drug affects them.
Hyperprolactinemia
Serum prolactin levels were not evaluated in the AUSTEDO
development program. Tetrabenazine, a closely related VMAT2 inhibitor, elevates
serum prolactin concentrations in humans. Following administration of 25 mg of
tetrabenazine to healthy volunteers, peak plasma prolactin levels increased
4-to 5-fold.
Tissue culture experiments indicate that approximately
one-third of human breast cancers are prolactin-dependent in vitro, a factor of
potential importance if AUSTEDO is being considered for a patient with previously
detected breast cancer. Although amenorrhea, galactorrhea, gynecomastia, and
impotence can be caused by elevated serum prolactin concentrations, the
clinical significance of elevated serum prolactin concentrations for most
patients is unknown.
Chronic increase in serum prolactin levels (although not
evaluated in the AUSTEDO or tetrabenazine development programs) has been
associated with low levels of estrogen and increased risk of osteoporosis. If
there is a clinical suspicion of symptomatic hyperprolactinemia, appropriate
laboratory testing should be done and consideration should be given to
discontinuation of AUSTEDO.
Binding To Melanin-Containing Tissues
Since deutetrabenazine or its metabolites bind to
melanin-containing tissues, it could accumulate in these tissues over time.
This raises the possibility that AUSTEDO may cause toxicity in these tissues
after extended use. Neither ophthalmologic nor microscopic examination of the
eye has been conducted in the chronic toxicity studies in a pigmented species
such as dogs. Ophthalmologic monitoring in humans was inadequate to exclude the
possibility of injury occurring after long-term exposure.
The clinical relevance of deutetrabenazine’s binding to
melanin-containing tissues is unknown. Although there are no specific
recommendations for periodic ophthalmologic monitoring, prescribers should be
aware of the possibility of long-term ophthalmologic effects [see CLINICAL
PHARMACOLOGY].
Patient Counseling Information
Advise the patient or caregiver to read the FDA-approved
patient labeling (Medication Guide).
Administration Instructions
Advise patients to take AUSTEDO with food. AUSTEDO
tablets should be swallowed whole and not chewed, crushed, or broken [see DOSAGE
AND ADMINISTRATION].
Risk Of Depression And Suicide In Patients With Huntington’s
Disease
Advise patients, their caregivers, and families that
AUSTEDO may increase the risk of depression, worsening depression, and suicidality,
and to immediately report any symptoms to a healthcare provider [see CONTRAINDICATIONS,
WARNINGS AND PRECAUTIONS].
Prolongation Of The QTc Interval
Inform patients to consult their physician immediately if
they feel faint, lose consciousness, or have heart palpitations [see WARNINGS
AND PRECAUTIONS]. Advise patients to inform physicians that they are taking
AUSTEDO before any new drug is taken.
Risk Of Sedation And Somnolence
Advise patients that AUSTEDO may cause sedation and
somnolence and may impair the ability to perform tasks that require complex
motor and mental skills. Until they learn how they respond to a stable dose of
AUSTEDO, patients should be careful doing activities that require them to be
alert, such as driving a car or operating machinery [see WARNINGS AND
PRECAUTIONS].
Interaction With Alcohol Or Other Sedating Drugs
Advise patients that alcohol or other drugs that cause
sleepiness will worsen somnolence [see DRUG INTERACTIONS].
Concomitant Medications
Advise patients to notify their physician of all
medications they are taking and to consult with their healthcare provider
before starting any new medications because of a potential for interactions [see
CONTRAINDICATIONS and DRUG INTERACTIONS].
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Carcinogenesis
No carcinogenicity studies were performed with
deutetrabenazine.
No increase in tumors was observed in p53+/– transgenic
mice treated orally with tetrabenazine at doses of 0, 5, 15, and 30 mg/kg/day
for 26 weeks.
Mutagenesis
Deutetrabenazine and its deuterated α-HTBZ and
β-HTBZ metabolites were negative in in vitro (bacterial reverse mutation
and chromosome aberration in human peripheral blood lymphocytes) assays in the
presence or absence of metabolic activation and in the in vivo micronucleus
assay in mice.
Impairment Of Fertility
The effects of deutetrabenazine on fertility have not
been evaluated. Oral administration of deutetrabenazine (doses of 5, 10, or 30
mg/kg/day) to female rats for 3 months resulted in estrous cycle disruption at
all doses; the lowest dose tested was similar to the maximum recommended human
dose (48 mg/day) on a body surface area (mg/m²) basis.
Oral administration of tetrabenazine (doses of 5, 15, or
30 mg/kg/day) to female rats prior to and throughout mating, and continuing
through day 7 of gestation, resulted in disrupted estrous cyclicity at doses
greater than 5 mg/kg/day. No effects on mating and fertility indices or sperm
parameters (motility, count, density) were observed when males were treated
orally with tetrabenazine at doses of 5, 15 or 30 mg/kg/day prior to and
throughout mating with untreated females.
Use In Specific Populations
Pregnancy
Risk Summary
There are no adequate data on the developmental risk
associated with the use of AUSTEDO in pregnant women. Administration of deutetrabenazine
to rats during organogenesis produced no clear adverse effect on embryofetal
development. However, administration of tetrabenazine to rats throughout
pregnancy and lactation resulted in an increase in stillbirths and postnatal
offspring mortality [see Data].
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. The background risk of major
birth defects and miscarriage for the indicated population is unknown.
Data
Animal Data
Oral administration of deutetrabenazine (5, 10, or 30
mg/kg/day) or tetrabenazine (30 mg/kg/day) to pregnant rats during organogenesis
had no clear effect on embryofetal development. The highest dose tested was 6
times the maximum recommended human dose of 48 mg/day, on a body surface area
(mg/m²) basis.
The effects of deutetrabenazine when administered during
organogenesis to rabbits or during pregnancy and lactation to rats have not
been assessed.
Tetrabenazine had no effects on embryofetal development
when administered to pregnant rabbits during the period of organogenesis at
oral doses up to 60 mg/kg/day. When tetrabenazine was administered to female
rats (doses of 5, 15, and 30 mg/kg/day) from the beginning of organogenesis
through the lactation period, an increase in stillbirths and offspring
postnatal mortality was observed at 15 and 30 mg/kg/day, and delayed pup
maturation was observed at all doses.
Lactation
Risk Summary
There are no data on the presence of deutetrabenazine or
its metabolites in human milk, the effects on the breastfed infant, or the
effects of the drug on milk production.
The developmental and health benefits of breastfeeding
should be considered along with the mother’s clinical need for AUSTEDO and any
potential adverse effects on the breastfed infant from AUSTEDO or from the
underlying maternal condition.
Pediatric Use
Safety and effectiveness in pediatric patients have not
been established.
Geriatric Use
Clinical studies of AUSTEDO did not include sufficient
numbers of subjects aged 65 and over to determine whether they respond
differently from younger subjects. Other reported clinical experience has not
identified differences in responses between the elderly and younger patients.
In general, dose selection for an elderly patient should be cautious, usually
starting at the low end of the dosing range, reflecting the greater frequency
of hepatic, renal, and cardiac dysfunction, and of concomitant disease or other
drug therapy.
Hepatic Impairment
The effect of hepatic impairment on the pharmacokinetics
of deutetrabenazine and its primary metabolites has not been studied; however,
in a clinical study conducted with tetrabenazine, a closely related VMAT2
inhibitor, there was a large increase in exposure to tetrabenazine and its
active metabolites in patients with hepatic impairment. The clinical
significance of this increased exposure has not been assessed, but because of
concerns for a greater risk for serious adverse reactions, the use of AUSTEDO
in patients with hepatic impairment is contraindicated [see CONTRAINDICATIONS,
CLINICAL PHARMACOLOGY].
Poor CYP2D6 Metabolizers
Although the pharmacokinetics of deutetrabenazine and its
metabolites have not been systematically evaluated in patients who do not
express the drug metabolizing enzyme, it is likely that the exposure to
α-HTBZ and β-HTBZ would be increased similarly to taking a strong
CYP2D6 inhibitor (approximately 3-fold). In patients who are CYP2D6 poor
metabolizers, the daily dose of AUSTEDO should not exceed 36 mg (maximum single
dose of 18 mg) [see DOSAGE AND ADMINISTRATION and CLINICAL
PHARMACOLOGY].