Imagine a world where your child's daily struggles with tummy troubles could be eased by a simple pill – but is it as safe as it sounds? That's the big question swirling around new research on tenapanor, a promising treatment for kids dealing with irritable bowel syndrome with constipation (IBS-C). If you're a parent, caregiver, or healthcare pro, stick around; this could change how we tackle this common yet frustrating issue in young patients.
Dr. Thomas Wallach, a leading expert in pediatric gastroenterology from SUNY Downstate Health Sciences University in New York, shared insights on the latest phase 3 safety data for tenapanor during the 2025 North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) Annual Meeting in Chicago, Illinois. The findings come from the R-ALLY trial and its open-label extension, focusing on how well this medication holds up in adolescents aged 12 to under 18 with IBS-C.
For those new to this, tenapanor is a groundbreaking drug – it's the first of its kind to target a protein called sodium/hydrogen exchanger isoform 3 (NHE3) in the gut. Think of NHE3 as a gatekeeper that controls how water moves in and out of your intestines. By blocking it, tenapanor encourages the colon to release more fluid, making stools softer and easier to pass. Unlike traditional laxatives that might require you to drink lots of water (like polyethylene glycol, commonly known as MiraLAX), this one works by prompting your body to naturally produce more moisture in the intestines. It's like giving your digestive system a gentle nudge to flush things out more smoothly, potentially easing the bloating, cramping, and discomfort tied to constipation or IBS-C.
The R-ALLY study enrolled 77 teens in this age group, randomly assigning them to either tenapanor at 25 mg twice a day, 50 mg twice a day, or a placebo for a 12-week period. After that, 56 participants who finished the initial phase moved into a 40-week open-label extension, where everyone received the active drug to gather more long-term info. The preliminary results? Tenapanor appeared safe and well-tolerated, with no serious adverse events linked to the treatment. Sure, some minor issues popped up, like diarrhea or overflow incontinence (that's when stool accidentally leaks because the bowel is too full), but these were mild, resolved quickly, and mostly unrelated to the drug – except for the diarrhea, which you'd expect from anything that loosens things up.
But here's where it gets controversial... This safety profile mirrors what we've seen in adult studies, where tenapanor has shown solid results for IBS-C without major red flags. Yet, critics might argue that just because it works well in grown-ups doesn't guarantee it's foolproof for kids. After all, children's bodies are still developing – their guts, livers, and other systems mature at different rates, and what seems harmless in adults could pose unexpected risks for teens. For instance, while the trial reported no serious problems, some parents worry about long-term effects we haven't spotted yet, especially since this is interim data. Is this the game-changer we need, or are we rushing to adopt a new pill without seeing the full picture? And this is the part most people miss: without proven efficacy data yet, we're basing comfort on safety alone – a bold leap that could spark debates in pediatric care.
In this exclusive Q&A with Contemporary Pediatrics, Dr. Wallach dives deeper into the study's implications, explaining why tenapanor could fill a crucial gap in treatment options for pediatric IBS-C.
Contemporary Pediatrics: Could you walk us through the R-ALLY trial on tenapanor for kids with IBS-C, including your take on the blinded safety data from the phase 3 open-label extension?
Dr. Thomas Wallach: Tenapanor represents an innovative approach to constipation relief. Beyond just helping with bowel movements, it might offer extra benefits for the gut's protective lining. It achieves this by inhibiting NHE3, which ultimately leads the colon to secrete additional fluid into the intestines. This differs from conventional laxatives, such as osmotic ones like polyethylene glycol (think MiraLAX), where you ingest a substance that retains water in your digestive tract to soften stool.
Instead, tenapanor and similar meds prompt the intestines to produce more water internally, resulting in looser, more manageable bowel movements and helping alleviate IBS-C symptoms. We've seen positive results in adult trials – effective relief with a strong safety record for both regular constipation and IBS-C. Now, we're extending this research to teens aged 12-18, with plans for another study on younger children soon. This phase 3 trial's blinded safety analysis is crucial, as it helps confirm the drug's tolerability in a pediatric setting.
Contemporary Pediatrics: What key findings from the study did you highlight at NASPGHAN 2025?
Dr. Wallach: When transitioning a medication from adults to children, we always ask two critical questions: First, does the underlying condition behave similarly, meaning will the drug's mechanism yield the same results? Second, are there unforeseen safety concerns unique to kids? Remember, children aren't simply miniature versions of adults; their organs and systems evolve differently over time. Something beneficial for adults might carry risks for younger patients – or vice versa. Our goal with these studies is to verify comparable efficacy and identify any new safety signals.
This abstract captures the safety outcomes from our nearly completed pediatric trial, involving 12-18-year-olds on standard tenapanor doses alongside a control group. We're thrilled to report that, aside from predictable minor side effects like loose stools (which aligns with its laxative action), no significant adverse events stood out – echoing the adult data. Essentially, the main issues are those typical of any bowel-softening treatment: sometimes it works a bit too effectively, leading to temporary looseness. As a preliminary finding, this reassures us and supports cautious optimism for using tenapanor in kids. While efficacy isn't proven here – that's forthcoming when the full trial wraps up – these results suggest pediatric safety will likely match the high standards seen in adults, building on earlier hints of similar effectiveness.
Importantly, this doesn't mean we should jump straight to widespread use. Efficacy and safety are both essential pillars of patient care. If you're facing a tough case and considering alternatives, the safety profile here gives me confidence in trying tenapanor. However, I wouldn't recommend it universally just yet without confirmed benefits. That said, it points to a promising path forward.
In pediatric constipation management, our go-to options have traditionally been stool softeners (like mineral oil) or bulking agents (such as fiber supplements, MiraLAX, or lactulose). Then there are prokinetic or stimulant laxatives (think senna or bisacodyl). Each has drawbacks: fiber can cause bloating and gas, MiraLAX requires large volumes of unappetizing liquid that might be hard to stomach, and stimulants can irritate the gut or lead to dependency. For kids with IBS-C, these challenges amplify – many have sensory sensitivities or neurodiversity that make bulky, tasteless drinks a nightmare, reducing compliance and worsening issues. Plus, some children have stomach capacity limits due to chronic illnesses, making high-volume treatments impractical.
That's where tenapanor shines: it's a low-volume pill or liquid option that's easier to administer and potentially more appealing. While other pill-based meds exist, they're often less researched, not formally approved for kids, and pricey with variable results. Tenapanor addresses a real unmet need for compact, effective relief. Constipation affects millions – it's a major driver of abdominal pain that persists into adulthood, contributing to complications like diverticulitis later in life. Estimates suggest up to half the population deals with it chronically, and tackling it early is key. The colon functions like a muscle; intervening in childhood helps it recover better, potentially preventing lifelong struggles. As connective tissues and muscles heal more readily at young ages, fixing constipation now could mean fewer problems down the road. This isn't just about occasional discomfort – it's about preventing broader health burdens and improving quality of life.
Reference
Williams N, Wallach T, Ringheanu M, et al. SAFETY AND TOLERABILITY OF TENAPANOR IN PEDIATRIC PATIENTS WITH IRRITABLE BOWEL SYNDROME WITH CONSTIPATION: AN ANALYSIS OF BLINDED SAFETY DATA FROM A PHASE 3 STUDY AND ITS OPEN-LABEL EXTENSION. Abstract. Presented at: 2025 NASPGHAN Annual Meeting. November 5-9, 2025. Chicago, Illinois.
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What do you think – is tenapanor the breakthrough pediatric constipation treatment we've been waiting for, or should we hold off until full efficacy data arrives? Could relying on safety alone for new drugs in kids be risky, especially with developmental differences at play? Share your opinions or experiences in the comments below; I'd love to hear if this resonates with you or if you see it differently!
