Warnings for Filspari
Included as part of the PRECAUTIONS section.
Precautions for Filspari
Hepatotoxicity
Elevations in ALT or AST of at least 3-fold ULN have been observed in up to 3.5% of FILSPARI-treated patients, including cases confirmed with rechallenge [see ADVERSE REACTIONS]. While no concurrent elevations in bilirubin greater than 2-times ULN or cases of liver failure were observed in FILSPARI-treated patients in clinical trials, some endothelin receptor antagonists have caused elevations of aminotransferases, hepatotoxicity, and liver failure. To reduce the risk of potential serious hepatotoxicity, measure serum aminotransferase levels and total bilirubin prior to initiation of treatment and monthly for the first 12 months, then every 3 months during treatment [see DOSAGE AND ADMINISTRATION].
Advise patients with symptoms suggesting hepatotoxicity (nausea, vomiting, right upper quadrant pain, fatigue, anorexia, jaundice, dark urine, fever, or itching) to immediately stop treatment with FILSPARI and seek medical attention. If aminotransferase levels are abnormal at any time during treatment, interrupt FILSPARI and monitor as recommended [see DOSAGE AND ADMINISTRATION].
Consider re-initiation of FILSPARI only when hepatic enzyme levels and bilirubin return to pretreatment values and only in patients who have not experienced clinical symptoms of hepatotoxicity [see DOSAGE AND ADMINISTRATION].
Avoid initiation of FILSPARI in patients with elevated aminotransferases (greater than 3Âtimes ULN) prior to drug initiation because monitoring hepatotoxicity in these patients may be more difficult and these patients may be at increased risk for serious hepatotoxicity [see DOSAGE AND ADMINISTRATION, and WARNINGS AND PRECAUTIONS].
Embryo-Fetal Toxicity
Based on data from animal reproduction studies, FILSPARI can cause fetal harm when administered to a pregnant patient and is contraindicated during pregnancy. Advise patients who can become pregnant of the potential risk to a fetus. Obtain a pregnancy test prior to initiation of treatment with FILSPARI, monthly during treatment, and one month after discontinuation of treatment. Advise patients who can become pregnant to use effective contraception prior to initiation of treatment, during treatment, and for one month after discontinuation of treatment with FILSPARI [see DOSAGE AND ADMINISTRATION, WARNINGS AND PRECAUTIONS and Use In Specific Populations].
FILSPARI REMS
For all patients, FILSPARI is available only through a restricted program under a REMS called the FILSPARI REMS because of the risk of hepatotoxicity and embryo-fetal toxicity [see CONTRAINDICATIONS, WARNINGS AND PRECAUTIONS, Use In Specific Populations].
Important requirements of the FILSPARI REMS include the following:
- Prescribers must be certified with the FILSPARI REMS by enrolling and completing training.
- All patients must enroll in the FILSPARI REMS prior to initiating treatment and comply with monitoring requirements [see DOSAGE AND ADMINISTRATION, WARNINGS AND PRECAUTIONS, Use In Specific Populations].
- Pharmacies that dispense FILSPARI must be certified with the FILSPARI REMS and must dispense only to patients who are authorized to receive FILSPARI.
Further information is available at www.filsparirems.com or 1-833-513-1325.
Hypotension
Hypotension has been observed in patients treated with ARBs and endothelin receptor antagonists (ERAs) and was observed in clinical studies with FILSPARI. In the PROTECT trial, there was a greater incidence of hypotension-associated adverse events, some serious, including dizziness, in patients treated with FILSPARI compared to irbesartan [see ADVERSE REACTIONS].
In patients at risk for hypotension, consider eliminating or adjusting other antihypertensive medications and maintaining appropriate volume status.
If hypotension develops, despite elimination or reduction of other antihypertensive medications, consider a dose reduction or dose interruption of FILSPARI. A transient hypotensive response is not a contraindication to further dosing of FILSPARI, which can be given once blood pressure has stabilized.
Acute Kidney Injury
Monitor kidney function periodically. Drugs that inhibit the renin-angiotensin system can cause acute kidney injury. Patients whose kidney function may depend in part on the activity of the renin-angiotensin system (e.g., patients with renal artery stenosis, chronic kidney disease, severe congestive heart failure, or volume depletion) may be at particular risk of developing acute kidney injury on FILSPARI. Consider withholding or discontinuing therapy in patients who develop a clinically significant decrease in kidney function while on FILSPARI.
Hyperkalemia
Monitor serum potassium periodically and treat appropriately. Patients with advanced kidney disease or taking concomitant potassium-increasing drugs (e.g., potassium supplements, potassium-sparing diuretics), or using potassium-containing salt substitutes are at increased risk for developing hyperkalemia. Dosage reduction or discontinuation of FILSPARI may be required [see DOSAGE AND ADMINISTRATION, ADVERSE REACTIONS].
Fluid Retention
Fluid retention may occur with endothelin receptor antagonists and has been observed in clinical studies with FILSPARI [see ADVERSE REACTIONS]. FILSPARI has not been evaluated in patients with heart failure.
If clinically significant fluid retention develops, evaluate the patient to determine the cause and the potential need to initiate or modify the dose of diuretic treatment then consider modifying the dose of FILSPARI.
Patient Counseling Information
Advise patients to read the FDA-approved patient labeling (Medication Guide).
Restricted Access
Advise the patient that FILSPARI is only available through a restricted access program called the FILSPARI REMS.
As a component of the FILSPARI REMS, prescribers must review the contents of the FILSPARI Medication Guide with the patient before initiating FILSPARI.
Instruct patients that the risks associated with FILSPARI include:
Hepatotoxicity
Advise patients with symptoms suggesting hepatotoxicity (nausea, vomiting, right upper quadrant pain, fatigue, anorexia, jaundice, dark urine, fever, or itching) to immediately stop taking FILSPARI and seek medical attention [see DOSAGE AND ADMINISTRATION, WARNINGS AND PRECAUTIONS].
Embryo-Fetal Toxicity
Educate and counsel patients who can become pregnant about the need to use reliable methods of contraception prior to treatment with FILSPARI, during treatment and for one month after treatment discontinuation. Patients who can become pregnant must have pregnancy tests prior to treatment with FILSPARI, monthly during treatment, and one month after treatment discontinuation [see DOSAGE AND ADMINISTRATION, CONTRAINDICATIONS, WARNINGS AND PRECAUTIONS, Use In Specific Populations].
Patients should be instructed to immediately contact their physician if they suspect they may be pregnant. Patients should seek additional contraceptive advice from a gynecologist or similar expert as needed.
Educate and counsel patients who can become pregnant on the use of emergency contraception in the event of unprotected sex or contraceptive failure.
Advise patients to contact their gynecologist or healthcare provider if they want to change the form of birth control which is used to ensure that another acceptable form of birth control is selected.
Advise the patient that FILSPARI is available only from certified pharmacies that are enrolled in the FILSPARI REMS.
Patients must sign the FILSPARI REMS Patient Enrollment Form to confirm that they understand the risks of FILSPARI.
Lactation
Advise patients not to breastfeed during treatment with FILSPARI [see Use In Specific Populations].
Drug Interactions
Advise patients to inform their healthcare provider of all concomitant medications, including prescription medications, over-the-counter drugs, vitamins/supplements, herbal products, and grapefruit [see CONTRAINDICATIONS, WARNINGS AND PRECAUTIONS, DRUG INTERACTIONS].
Other Risks Associated With FILSPARI
Inform patients of other risks associated with FILSPARI, including:
- Hypotension: Advise patients to remain hydrated [see WARNINGS AND PRECAUTIONS].
- Hyperkalemia: Advise patients not to use potassium supplements or salt substitutes that contain potassium without consulting their healthcare provider [see WARNINGS AND PRECAUTIONS].
Dosing
Advise patients to take the full daily dose with water prior to the morning or evening meal. Maintain the same dosing pattern in relationship to meals. If a dose is missed, take the next dose at the regularly scheduled time. Do not take double or extra doses [see DOSAGE AND ADMINISTRATION].
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, And Impairment Of Fertility
Carcinogenesis
In the two-year rat carcinogenicity study, there was no evidence of increased incidence of neoplasia in male rats orally administered at 15 mg/kg/day (the only dose evaluated) and in female rats orally administered up to 240 mg/kg/day, which provided an exposure approximately 0.7 times and 26 times the AUC at the MRHD, respectively. In the 26-week transgenic mouse study, there was no evidence of increased incidence of neoplasia in male and female mice orally administered sparsentan at doses up to 600 mg/kg/day.
Mutagenesis
There was no evidence of mutagenicity or clastogenicity for sparsentan in in vitro bacteria reverse mutation and chromosomal aberration assays, or in an in vivo rat micronucleus study.
Impairment Of fertility
In a fertility and early embryonic development study in rats, oral administration of sparsentan at doses of 20, 80, and 320 mg/kg/day for at least 36 (females) and 49 (males) days did not result in any adverse effects on estrous cycles, mating, fertility, sperm evaluation, or pregnancy incidence at doses up to 320 mg/kg/day, which provided approximately 10 and 14 times the AUC at the MRHD for males and females, respectively. Male reproductive organ toxicity was not evident in chronic toxicity studies with sparsentan at exposures up to 10 times and 1.3 times the AUC at the MRHD in rats and monkeys, respectively.
Use In Specific Populations
Pregnancy
Risk Summary
Based on data from animal reproductive toxicity studies, FILSPARI can cause fetal harm, including birth defects and fetal death, when administered to a pregnant patient and is contraindicated during pregnancy [see CONTRAINDICATIONS]. Available data from reports of pregnancy in clinical trials with FILSPARI are insufficient to identify a drug-associated risk of major birth defects, miscarriage, or other adverse maternal or fetal outcomes. In animal reproduction studies, oral administration of sparsentan to pregnant rats throughout organogenesis at 10-times the maximum recommended human dose (MRHD) in mg/day caused teratogenic effects in rats, including craniofacial malformations, skeletal abnormalities, increased embryo-fetal lethality, and reduced fetal weights (see Data). Advise pregnant patients of the potential risk to the fetus.
The background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. 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.
Data
Animal Data
In embryo-fetal development studies in pregnant rats and rabbits, teratogenicity and/or developmental toxicity were observed, which were attributed to the antagonism of endothelin type A (ETA) and angiotensin II type 1 (AT1) receptors.
In pregnant rats, oral administration of sparsentan throughout organogenesis at doses of 80, 160, and 240 mg/kg/day resulted in dose-dependent teratogenic effects in the form of craniofacial malformations, skeletal abnormalities, increased embryo-fetal lethality, and reduced fetal weights at all doses tested. The area under the curve (AUC) at the lowest dose tested (80 mg/kg/day) was approximately 10 times the AUC at the MRHD of 400 mg/day. In pregnant rabbits, oral administration of sparsentan throughout organogenesis at doses of 2.5, 10 and 40 mg/kg/day resulted in maternal death and abortions at 10 and 40 mg/kg/day which provided exposures approximately 0.1 times and 0.2 times the AUC at the MRHD, respectively. An increase in a fetal variation (supernumerary cervical ribs) occurred at the high dose of 40 mg/kg/day.
In the pre-and postnatal development study in rats, oral administration of sparsentan during pregnancy and the lactational period at doses of 5, 20, or 80 mg/kg/day resulted in maternal death, body weight loss/reduced body weight gain, and adverse clinical signs at 80 mg/kg/day. An increase in pup deaths occurred at 80 mg/kg/day (approximately 10 times the AUC at MRHD) during the neonatal period through weaning, and decreased growth occurred at ≥ 20 mg/kg/day (approximately 2.6 times the AUC at the MRHD) after weaning. The NOAEL for pre-and postnatal development in rats was 5 mg/kg/day, approximately 0.7 times the AUC at the MRHD.
Lactation
Risk Summary
There are no data on the presence of sparsentan in human milk, the effects on the breastfed infant, or the effect on milk production. Because of the potential for adverse reactions, such as hypotension in breastfed infants, advise patients not to breastfeed during treatment with FILSPARI.
Females And Males Of Reproductive Potential
Based on data from animal reproductive toxicity studies, FILSPARI can cause fetal harm, including birth defects and fetal death, when administered to a pregnant patient and is contraindicated during pregnancy [see CONTRAINDICATIONS, Use In Specific Populations].
Pregnancy Testing
Verify that patients who can become pregnant are not pregnant prior to initiating FILSPARI, monthly during treatment, and one month after discontinuation of treatment. The patient should contact their physician immediately for pregnancy testing if onset of menses is delayed or pregnancy is suspected. If the pregnancy test is positive, the physician and patient must discuss the risks to their pregnancy and the fetus.
Contraception
Patients who can become pregnant who are using FILSPARI must use an effective method of contraception prior to initiation of treatment, during treatment, and for one month after discontinuation of treatment with FILSPARI to prevent pregnancy [see WARNINGS AND PRECAUTIONS].
Pediatric Use
The safety and efficacy of FILSPARI in pediatric patients have not been established.
Geriatric Use
Of the total number of subjects in the PROTECT study of FILSPARI, 15 (7.4%) were 65 and older. No overall differences in safety or effectiveness were observed between these subjects and younger subjects.
Hepatic Impairment
Avoid use of FILSPARI in patients with any hepatic impairment (Child-Pugh class A-C) because of the potential risk of serious liver injury [see WARNINGS AND PRECAUTIONS, CLINICAL PHARMACOLOGY].