Teva's Experimental Antibody Shows Promise Against Celiac Disease in Mid-Stage Trial

For someone with celiac disease, a hidden trace of gluten in a meal isn't just an inconvenience. It can trigger days of pain, fatigue, and digestive distress, along with quiet damage to the small intestine that a person may not even feel happening. That's the daily reality for an estimated 5.1 million people across the U.S. and the five largest EU countries who live with this autoimmune condition, according to figures from Teva Pharmaceutical Industries.

Right now, the only real tool available is avoidance. Patients are told to strip gluten from their diets entirely and hope that's enough. It often isn't. Teva says roughly half of celiac patients continue to experience symptoms even while sticking to a gluten-free diet, a statistic that speaks to how incomplete current care really is.

That's the backdrop for news this week that Teva's experimental drug, TEV-53408, met its main goal in a Phase 2a clinical trial. The drug prevented intestinal damage in celiac patients exposed to gluten, according to topline results the company reported Wednesday. It's an early but meaningful signal in a disease area that has never had an FDA-approved medicine to call its own.

How the Drug Works and What the Trial Found

Celiac disease begins when the immune system mistakes gluten, a protein found in wheat, barley, and rye, for a threat. The body's response ends up damaging villi, the tiny finger-like projections lining the small intestine that absorb nutrients from food. Think of villi as the intestine's shag carpet, densely packed to maximize surface area for absorption. When that carpet gets flattened by chronic inflammation, the body simply can't take in nutrients the way it should.

TEV ’408 is designed to interrupt that process before it starts. It's a monoclonal antibody, a lab-made protein built to latch onto a specific target, in this case interleukin-15, or IL-15. IL-15 is a signaling molecule that helps drive the immune-mediated inflammation behind celiac damage. Block the signal, the thinking goes, and you blunt the immune attack before it can flatten the villi.

The drug was discovered in Teva's own labs and engineered for injection under the skin rather than through an IV. It also carries a long half-life, meaning it stays active in the body for an extended period. Teva believes this could eventually allow dosing as infrequently as once every three months, a meaningful convenience for patients managing a chronic illness.

The Phase 2a study enrolled 50 adults with celiac disease who were already following a gluten-free diet and had minimal intestinal damage at the study's start. Two weeks after a single dose of either the drug or a placebo, participants underwent what's called a gluten challenge: eating gluten-containing food daily for six weeks to deliberately provoke the immune response researchers wanted to study. Doctors tracked what happened using intestinal biopsies and patient-reported symptom scores.

By week eight, Teva reported statistically significant and clinically meaningful protection against gluten-induced intestinal damage in patients who received TEV ’408, compared with those on placebo. Patients also reported lower gastrointestinal symptom scores, and the drug appeared safe and well tolerated throughout. Teva says it will share fuller data at a future scientific meeting, and the study will continue following participants through week 80 to gauge how durable the effect is and whether safety concerns emerge over a longer stretch.

"These results underscore the potential to move beyond managing gluten exposure and address celiac disease at its biological source," Teva Chief Medical Officer Eric Hughes said in a prepared statement. He added that the data strengthen the company's confidence in targeting the IL-15 pathway to reduce immune-driven intestinal damage more broadly.

Celiac disease isn't the only place Teva sees potential for this antibody. About two months before this announcement, the company reported encouraging Phase 1b results for TEV ’408 in vitiligo, a condition in which the immune system attacks pigment-producing skin cells, causing patches of discoloration. That program is now advancing to Phase 2b testing. Teva has also floated eosinophilic esophagitis, alopecia areata, and atopic dermatitis as other conditions where blocking IL-15 might help. For celiac disease alone, the company projects peak sales between $1.5 billion and $2 billion, according to an investor presentation.

Why It Matters

None of this happens in a vacuum. Teva isn't the only company chasing this biological pathway, and the competition says something about how much unmet need exists in this space.

Argenx made that clear when it acquired Forte Biosciences for $2.2 billion earlier this year, a deal that followed Forte's own encouraging early data on an antibody blocking CD122, a receptor subunit shared by both IL-2 and IL-15, in celiac disease and vitiligo. First Track Biotherapeutics is pursuing a similar CD122-targeting approach with its drug ANB033, aimed at celiac disease and eosinophilic esophagitis. Leerink Partners analyst David Risinger, who covers First Track, has argued that a drug hitting both IL-2 and IL-15 could offer a more comprehensive effect than Teva's IL-15-only approach, though he cautioned that claim still needs to be proven in the clinic. First Track expects preliminary data from its own Phase 1b celiac study, which has finished enrolling patients for the gluten challenge portion, sometime in the fourth quarter of this year.

For patients, this kind of competition is generally good news. Multiple companies racing toward the same biological target tends to speed up the overall pace of drug development, even if only one or two therapies eventually reach approval. Teva's next step is a multiple-dose Phase 2 study designed to nail down the right dose and treatment schedule ahead of a Phase 3 trial, the kind of large study regulators typically require before approving a new medicine. That work is being financially backed by a deal Teva struck with Royalty Pharma at the start of the year, which provides up to $500 million in support. In exchange, Teva would owe Royalty Pharma a milestone payment plus a royalty on global sales if TEV ’408 eventually reaches the market.

It's still early. Fifty patients and eight weeks of data don't guarantee a future FDA approval, and there's a long road of larger trials ahead before anyone with celiac disease could actually take this drug home. But for a disease that has never had a dedicated approved therapy, and for the roughly half of patients whose symptoms persist no matter how carefully they eat, even a preliminary signal like this one carries real weight.