Tenapanor hydrochloride
Brand names: IBSRELA
Boxed warning
WARNING: RISK OF SERIOUS DEHYDRATION IN PEDIATRIC PATIENTS IBSRELA is contraindicated in patients less than 6 years of age; in nonclinical studies in young juvenile rats administration of tenapanor caused deaths presumed to be due to dehydration [see Contraindications (4) , Use in Specific Populations (8.4) ]. Avoid use of IBSRELA in patients 6 years to less than 12 years of age [see Warnings and Precautions (5.1) , Use in Specific Populations (8.4) ]. The safety and effectiveness of IBSRELA have not been established in patients less than 18 years of age [see Use in Specific Populations (8.4) ] . WARNING: RISK OF SERIOUS DEHYDRATION IN PEDIATRIC PATIENTS See full prescribing information for complete boxed warning. IBSRELA is contraindicated in patients less than 6 years of age; in young juvenile rats, tenapanor caused death presumed to be due to dehydration. ( 4 , 8.4 ) Avoid use of IBSRELA in patients 6 years to less than 12 years of age. ( 5.1 , 8.4 ) The safety and effectiveness of IBSRELA have not been established in pediatric patients less than 18 years of age. ( 8.4 )
Warnings
5 WARNINGS AND PRECAUTIONS Diarrhea: Patients may experience severe diarrhea. If severe diarrhea occurs, suspend dosing and rehydrate patient. ( 5.2 ) 5.1 Risk of Serious Dehydration in Pediatric Patients IBSRELA is contraindicated in patients below 6 years of age. The safety and effectiveness of IBSRELA in patients less than 18 years of age have not been established. In young juvenile rats (less than 1 week old; approximate human age equivalent of less than 2 years of age), decreased body weight and deaths occurred, presumed to be due to dehydration, following oral administration of tenapanor. There are no data available in older juvenile rats (human age equivalent 2 years to less than 12 years). Avoid the use of IBSRELA in patients 6 years to less than 12 years of age. Although there are no data in older juvenile rats, given the deaths in younger rats and the lack of clinical safety and efficacy data in pediatric patients, avoid the use of IBSRELA in patients 6 years to less than 12 years of age [see Contraindications (4) , Warnings and Precautions (5.2) , Use in Specific Populations (8.4) ] . 5.2 Diarrhea Diarrhea was the most common adverse reaction in two randomized, double-blind, placebo-controlled trials of IBS-C. Severe diarrhea was reported in 2.5% of IBSRELA-treated patients [see Adverse Reactions (6.1) ] . If severe diarrhea occurs, suspend dosing and rehydrate patient.
Contraindications
4 CONTRAINDICATIONS IBSRELA is contraindicated in: Patients less than 6 years of age due to the risk of serious dehydration [see Warnings and Precautions (5.1) , Use in Specific Populations (8.4) ]. Patients with known or suspected mechanical gastrointestinal obstruction . Pediatric patients less than 6 years of age. ( 4 , 5.1 , 8.4 ) Patients with known or suspected mechanical gastrointestinal obstruction. ( 4 )
Overdose
10 OVERDOSAGE Based on nonclinical data, overdose of IBSRELA may result in gastrointestinal adverse effects such as diarrhea as a result of exaggerated pharmacology with a risk for dehydration if diarrhea is severe or prolonged [see Warnings and Precautions (5.1) ].
Drug interactions
7 DRUG INTERACTIONS OATP2B1 Substrates: Potential for reduced exposure of the concomitant drug (e.g., enalapril). Monitor for signs related to loss of efficacy and adjust the dosage of the concomitantly administered drug as needed. ( 7.1 ) 7.1 OATP2B1 Substrates Tenapanor is an inhibitor of intestinal uptake transporter, OATP2B1 [see Clinical Pharmacology (12.3) ] . Drugs which are substrates of OATP2B1 may have reduced exposures when concomitantly taken with IBSRELA. Monitor for signs related to loss of efficacy and adjust the dosage of concomitantly administered drug as needed. Enalapril is a substrate of OATP2B1. When enalapril was coadministered with tenapanor (30 mg twice daily for five days, a dosage 0.6 times the recommended dosage), the peak exposure (C max ) of enalapril and its active metabolite, enalaprilat, decreased by approximately 70% and total systemic exposures (AUC) decreased by approximately 50% to 65% compared to when enalapril was administered alone [see Clinical Pharmacology (12.3) ] . Monitor blood pressure and increase the dosage of enalapril, if needed, when IBSRELA is coadministered with enalapril.
Uses
1 INDICATIONS AND USAGE IBSRELA is indicated for treatment of irritable bowel syndrome with constipation (IBS-C) in adults. IBSRELA is a sodium/hydrogen exchanger 3 (NHE3) inhibitor indicated for treatment of irritable bowel syndrome with constipation (IBS-C) in adults. ( 1 )
Dosage forms & strengths
2 DOSAGE AND ADMINISTRATION The recommended dosage of IBSRELA in adults is 50 mg orally twice daily. The recommended dosage in adults is 50 mg, orally twice daily. ( 2 ) Take immediately prior to breakfast or the first meal of the day and immediately prior to dinner. ( 2 ) Administration Instructions Take IBSRELA immediately prior to breakfast or the first meal of the day and immediately prior to dinner [see Clinical Pharmacology (12.2) ] . If a dose is missed, skip the missed dose and take the next dose at the regular time. Do not take 2 doses at the same time.