by Ryan Cross on May 5th, 2025
Topas Therapeutics, a small German biotech company attempting to quell overactive immune systems, has revealed the first data from a study of its “tolerance induction” therapy for celiac disease. The results, to be presented at the Digestive Disease Week conference on Monday, come more than six months after Topas first declared success in the study via a press release, without divulging any data. The company discussed the therapy and shared the data with Endpoints News in an exclusive interview ahead of the conference, though many questions remain about the results. The 38-person trial focused on the safety of the company’s experimental nanoparticle treatment over seven weeks, its ability to steer immune cells toward a less inflammatory state, and patient-reported changes in gastrointestinal symptoms. Topas executives told Endpoints that the therapy was successful against those goals, even though granular data on safety and patient outcomes was missing from the presentation. They conceded that bigger and longer studies are still needed, but added that any relief from celiac disease would be a breakthrough.“There is both very much a medical need and big commercial opportunity in celiac,” Topas CEO Hugo Fry told Endpoints. Tolerizing the immune system Celiac disease is caused by an unwanted immune reaction to gluten, which is abundant in food. There’s no treatment or cure for the condition that, by some estimates, may affect as many as 1 in 100 people. Despite that, there are relatively few drug developers working on treatments. Topas is one of three companies, along with Anokion and Takeda, developing a potential immune tolerizing therapy in a Phase 2 study. Rather than merely tamping down on inflammation, the efforts aim to retrain the immune system to ignore triggers like gluten. “Tolerization is at that disease-modifying, almost curative end of the spectrum,” Fry said. It aims to do so by presenting nanoparticles decorated with tidbits of peptides that resemble the problematic parts of proteins that set off the immune system, known as antigens. For the celiac therapy, dubbed TPM502, the company uses three nanoparticles, each with a different antigenic peptide from the gluten protein. In many ways, the goal is opposite to that of a vaccine, which presents antigens to build the body’s reaction and create an immune response. Instead, Topas’ infused nanoparticles target specific cells in the liver that serve as a calming zone for T cells, where they learn to live peacefully alongside antigens that don’t warrant being attacked. Cristina de Min “That’s the body’s natural hub of induced tolerization,” Fry said. “And it pushes them through that natural route.” Celiac was a good place to start looking for signals that the tolerization approach was working because doctors can easily provoke the immune system to flare up by having participants consume gluten, said Topas chief medical officer Cristina de Min. First glimpse of data The company tested four doses of its nanoparticle therapy, ranging from 0.72 micromolar to 7.2 micromolar, in 26 patients. The other 12 patients got a placebo. Participants got the drug or placebo on day 1 and day 15 of the study and then consumed gluten a week later. De Min said that “the drug was remarkably safe,” largely resulting in side effects that resemble gluten consumption in celiac disease, including headache, pain, nausea and vomiting in 27 patients. But the company didn’t break this safety data down by side effect, or between participants who got the drug versus placebo. The company also said that there were three “grade 3” adverse events, the second highest severity, but didn’t say what they were. To get an idea of whether the treatment was working, Topas measured the release of the inflammatory immune protein IL-2 in response to being “challenged” with gluten. Only the highest dose of the therapy resulted in a significant decrease in IL-2 release. But when studying the gene expression of T cells before and after the therapy, the company found that all dose levels helped turn on genes that tamped down on inflammation and reduced genes that promoted inflammation. Topas also asked patients to rate their gastrointestinal symptoms before and after the treatment. The company said that people who got higher doses of the therapy had reduced symptoms, but the presentation was light on specific details. Topas emphasized that the study was not designed to test for efficacy. Another major caveat was the study’s strict inclusion criteria. Topas screened 391 people and recruited only one-tenth of them. Many prospective participants were excluded because they didn’t produce high enough levels of IL-2 in response to gluten consumption. “We wanted to make sure that only patients with measurable response would be involved,” de Min said. Even more patients were excluded because they didn’t have the certain immune system genotype that Topas focused on in this study. Topas is planning a Phase 2b study that will include a broader range of immune genotypes, accounting for 85% to 90% of people with celiac disease. Topas also wants to develop a tolerization therapy for type 1 diabetes, Fry said. But doing so will require more funding, and Fry is setting out to raise a €70 million Series D round. The company is currently funded through 2026 and isn’t planning to start a new study before then, he said.
Topas claims success in early test of ‘immune tolerance’ celiac therapy