Our First Discovery
Our unique discovery platform and deep understanding of the primary mechanism of sodium transport in the intestine resulted in our discovery and development of IBSRELA® (tenapanor), a first-in-class therapy, available in the U.S. and Canada for the treatment of adults with irritable bowel syndrome with constipation (IBS-C). IBSRELA is dosed as one 50mg tablet BID.
Learn More About IBSRELA.


IMPORTANT SAFETY INFORMATION
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. Avoid use of IBSRELA in patients 6 years to less than 12 years of age. The safety and effectiveness of IBSRELA have not been established in patients less than 18 years of age.
CONTRAINDICATIONS
- IBSRELA is contraindicated in patients less than 6 years of age due to the risk of serious dehydration.
- IBSRELA is contraindicated in patients with known or suspected mechanical gastrointestinal obstruction.
WARNINGS AND PRECAUTIONS
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.
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. If severe diarrhea occurs, suspend dosing and rehydrate patient.
MOST COMMON ADVERSE REACTIONS
The most common adverse reactions in IBSRELA-treated patients (incidence ≥2% and greater than placebo) were: diarrhea (16% vs 4% placebo), abdominal distension (3% vs <1%), flatulence (3% vs 1%) and dizziness (2% vs <1%).
INDICATION
IBSRELA (tenapanor) is indicated for the treatment of Irritable Bowel Syndrome with Constipation (IBS-C) in adults.
Please see full Prescribing Information, including Boxed Warning, for additional risk information.
What is IBS-C?
Irritable bowel syndrome with constipation (IBS-C) is a gastrointestinal disorder characterized by abdominal pain and constipation, that significantly impacts the health and quality of life of affected patients. IBS-C is a common condition with a multi-factorial pathophysiology. There are currently no specific tests or biomarkers for diagnosis of IBS-C. Therefore, IBS-C is diagnosed by symptoms and by eliminating other disorders.
It is estimated that there are ~11 million people in the U.S. with IBS-C.
What is Hyperkalemia?
Hyperkalemia is a potentially life-threatening condition in which blood levels of potassium are elevated above normal. Potassium is a nutrient that is critical to the normal function of nerve and muscle cells, including those in the heart. Normal potassium blood levels are tightly balanced and maintained primarily by the kidneys. For people with chronic kidney disease (CKD), heart failure, and diabetes, and particularly those also taking renin-angiotensin-aldosterone system (RAAS) inhibitors, there is a greater risk of developing hyperkalemia due to the kidneys' reduced ability to keep potassium in balance.
Several published guidelines have suggested that physicians should reduce, and possibly discontinue, RAAS inhibition when hyperkalemia develops in order to manage the risk of elevated potassium in CKD and heart failure patients. The alternative medications used to control hypertension, including diuretics and calcium channel blockers, are less effective than RAAS inhibitors, particularly in patients with failing kidneys and severe hypertension.
According to the 2015 publication Market Dynamix: Hyperkalemia, released by Spherix Global Insights, U.S. cardiologists reported that of the patients who would benefit from RAAS inhibition, up to 38% of patients with heart failure and up to 55% of patients with both heart failure and CKD are being administered a sub-optimal dose or none at all. Nephrologists reported that at least one-third of patients who would benefit from RAAS inhibition receive a sub-optimal dose or none at all. We believe there is clearly a strong medical need for new medications that control hyperkalemia in order to allow for optimal use of RAAS inhibitors in these patient populations.
It is estimated that approximately 2 million people in the U.S. with CKD and/or heart failure have hyperkalemia, which remains an emerging and unaddressed market, despite available treatments.
What is Hyperphosphatemia?
Hyperphosphatemia, a nearly universal condition in the more than 550,000 patients in the U.S. with CKD on dialysis, is an electrolyte disorder in which there is an elevated level of phosphate in the blood.
While dialysis is the basis for homeostatic electrolyte management, dialysis regimens are unable to successfully remove excess phosphate in order to achieve a neutral phosphate balance. As a result, approximately 80% of patients with CKD on dialysis require phosphate-lowering therapy on top of restrictive, low phosphorus diets.
Management of hyperphosphatemia has been a long-time challenge. While the 2017 Kidney Disease Improving Global Outcomes (KDIGO) clinical practice guidelines recommend lowering elevated phosphate levels toward the normal range (2.5-4.5 mg/dL or 0.81-1.45mmol/L), due to the difficulties in managing phosphorus, most clinicians target phosphorus levels between 3.5-5.5 mg/dL (1.13-1.78 mmol/L), based on the 2003 Kidney Disease Outcomes Quality Initiative (KDOQI) clinical practice guidelines.