Tenapanor shows favorable tolerability in IBS-C safety study

Tenapanor showed positive results in a safety extension study, which the manufacturer Ardelyx said will support a new drug application along with two successful phase 3 trials for constipation-predominant irritable bowel syndrome, according to a press release.

Tenapanor, a small-molecule NHE3 inhibitor, completed the safety extension of its phase 3 T3MPO program and showed even more favorable results for patients who also completed the T3MPO-1 and T3MPO-2 programs, according to the manufacturer.

“We are very excited to see that tenapanor was so well-tolerated in patients treated for up to a year, resulting in minimal treatment discontinuations,” David P. Rosenbaum, PhD, chief development officer of Ardelyx, said in the press release. “These findings, along with the large number of people who elected to stay on tenapanor treatment for such an extended period of time, reinforce tenapanor’s potential as an effective and well-tolerated chronic treatment for people with IBS-C.”

Patients who completed either of the previous two T3MPO programs were eligible for the T3MPO-3 program, totaling 240 patients treated. The patients in the study could continue taking tenapanor for up to a year.

Results from the T3MPO-3 program showed that tenapanor was even more well-tolerated than in previous trials, with just 9.2% of patients reporting diarrhea compared with 16% in T3MPO-2. Out of the overall discontinuation rate of 2.1%, only 1.7% of patients discontinued treatment due to diarrhea.

“The rate of diarrhea reported among patients was lower than that observed in both the T3MPO-1 and T3MPO-2 trials, which may further suggest that diarrhea occurs early in treatment and bowel movements can be normalized over time,” Rosenbaum said in the release.

The company said it plans to submit its first new drug application to FDA in the second half of 2018. – by Alex Young

Disclosures: Rosenbaum is employed by Ardelyx.