By Amy Ratner, Medical and Science News Analyst
Celiac disease experts from around the world met recently at Columbia University to discuss research that impacts patients, from the activity of their cells to the decisions they make about diet and healthcare in daily life.
“It’s a horse race,” said Joseph Murray, M.D., of the Mayo Clinic, summing up the push to get approval of treatments for celiac disease through the needed testing and approval processes.
“It’s not possible one drug will be able to treat all people with celiac disease,” said Francisco Leon, M.D., former chief medical officer and former chief executive officer of Celimmune, a clinical development stage immunotherapy company. “We are targeting every aspect of the disease. These are not ‘Me, too,’ drugs.”
Murray and Leon were among an international gathering of researchers at Columbia’s Celiac Disease Center International Symposium. While experts were enthusiastic about progress toward new treatments for celiac disease, they cautioned that it will be at least several years before any drug is available.
Latest on drug studies
In a preview of a new study due to be released soon, Leon showed that the molecule IL-15 plays a key role in the processes within the body that result in the symptoms of celiac disease and its most severe form, refractory celiac disease. Consequently, AMG 714, a drug that neutralizes IL-15 being developed by Celimmune, will move into the next level of study looking at celiac disease patients who do not respond to the gluten-free diet. Amgen, a California-based biotechnology company, recently acquired Celimmune, where Leon is now a consultant.
The status of other potential treatments for celiac disease was also updated including: a vaccine being developed by ImmusanT, nanoparticle therapy by Cour Pharmaceutical and enzymes that break down gluten by ImmunogenX. Immusant’s Nexvax2 is moving to Phase 2 clinical study, ImmunogenX is studying how latiglutenase might help those with celiac disease symptoms and positive blood tests and Cour’s TIMP-GLIA is about to begin being tested in humans.
Meanwhile, a potential on-off switch for celiac disease was detailed by Chaitan Khosla, Ph.D., professor of chemistry, chemical engineering and biochemistry at Stanford University.
His laboratory has determined that inactive tissue transglutaminate 2 (TG2) found throughout the body is “turned on” in the intestine by inflammatory triggers in those who have celiac disease. TG2 is activated when its disulfide bond is broken. Now Stanford researchers have found an enzyme that reforms the bond and could turn off the TG2 protein.
“We are interested in TG2 as a drug target because it is the primary auto-antigen,” Khosla said. “If you could block the reach of TG2, you could mitigate this process.” The study is in early stages, as scientists have only looked at the behavior in cells. Next, they plan to test it in mouse models and ultimately in human study participants. (Look for more details on the study on the Beyond Celiac website’s research news page soon.)
At times celiac disease research can sound a bit like alphabet soup, with B-cells and T-cells part of the discussion along with IL-15 and TG2. But each plays a role in the celiac disease process and offers researchers potential ways to treat patients, who currently have to rely on the gluten-free diet to control the symptoms and intestinal damage caused by the gluten protein in wheat, barley and rye.
Experts have been working on celiac disease at an accelerated pace, trying to determine how best to diagnose, manage, treat and ultimately cure the condition. As drugs move through the stages of clinical trials mandated by the U.S. Food and Drug Administration, they most likely will first be used in addition to the diet and then be explored further as a way to replace it.
The “Doggie Bag”
Jocelyn Silvester, M.D., director of research at the Celiac Disease Program at Boston Children's Hospital, gave preliminary details about the so-called DOGGIE BAG study being done with the Manitoba Celiac Disease Cohort. Patients have been providing food, urine and stool samples that have been tested for gluten content to determine how much the patients are being exposed. Both stool and urine tests that detect gluten are frequently positive, early results show. Likewise food samples often tested positive for gluten content, some with levels below the 20 parts per million considered safe for those who have celiac disease and some far above that standard.
The study is expected to be published soon, but Silvester said some conclusions can already be drawn.
She said there is no good way to know if a person is getting gluten in their diet, gluten is found everywhere, and more studies are needed to clarify the role of urine and stool tests being used in research. These tests are now also available for home use.
“Zero gluten is an aspiration rather than a realistic goal,” Silvester said in describing adherence to the gluten-free diet.
Meanwhile, patients who are accustomed to the gluten-free diet as the only treatment for the disease, are weighing whether they want to take a drug, including how often and in what form.
Patients on a panel at the symposium expressed a wide range of views, from being suspicious of new treatments, to being reluctant to take a pill or shot once a day, to seeing new treatments as needed relief from the strain of uncertainty about cross-contamination in the diet.
One patient said his initial reaction to the idea of taking a drug, was “no way, no how.” But as he weighed the question, he concluded that an annual injection, a pill every few months or a morning after type of medication to protect against cross-contact are options he would consider.
Another said she is plagued by anxiety about the diet and is worried about its impact when she begins college next year. Consequently, she would consider taking a daily pill or injection. “I have to think about gluten every day and that would lessen my concern,” she said.
A third said that in theory she would take a pill or injection every day, but she would be even more interested in new treatments if her daughter is ever diagnosed with celiac disease, a possibility due to the genetic component of the disease.
Columbia researcher Norelle Reilly, M.D., assistant professor of pediatrics at Columbia University, presented preliminary results of a survey of parent’s opinions about whether they would give their children a drug, were one to become available. Overall, parents said yes, though they did have concerns about safety.
Nearly 1,000 survey responses from parents of children with celiac disease who were 17 and younger were tallied. Ninety-three percent of parents said they would like to see therapies in addition to the gluten-free diet. Meanwhile, 46 percent of children said yes, 25 percent said no, and 30 percent were too young to answer.
Parents noted that the safety of medications and the potential side effects would be the main factors they would weigh before giving any treatment to their children.
Healthcare for young adults
Reilly also reported on a study regarding follow-up healthcare for children which focused on transitioning a child from pediatric to adult healthcare providers. As children become young adults they don’t continue celiac disease care because there are no prescription drugs and therefore no need to see a doctor for a renewal. Also, young adults don’t know who to go to or have the time, or in some cases, the needed insurance coverage.
The study found that children were more likely to get follow-up care as adults if they: are introduced at around 16 years old to the idea that they will eventually need an adult gastroenterologist; have a pediatric gastroenterologist who initiates a plan for a transfer; and complete the transfer of care by 18 years old.
Although children often do not get follow-up care when they become young adults, the study found that those who are diagnosed young and have no symptoms are the least likely to get celiac disease follow up.
Risk, diagnosis, prevalence, gender and beer
Symposium speakers touched on a wide range of topics. Following are some key point they made.
When it comes to what puts people at risk for celiac disease, Jonas Ludvigsson, M.D., an expert in the epidemiology of celiac disease and professor in the department of medical epidemiology and biostatistics at Sweden’s Karolinska Institutet, said that in addition to the needed genes and exposure to gluten, viruses and the makeup of the bacteria in the gut, called the microbiome, are among key factors.
In discussing diagnosis, Murray pointed to the results of one study that found more than 50 percent of those with celiac disease have been diagnosed, a sharp increase from the less than 20 percent typically reported. He said it’s not clear if the increase is a true reflection of the diagnosis rate or a fluke and that more study is needed.
Murray said the prevalence of celiac disease seems to have peaked, but he is worried about people who have celiac disease who are hidden among those who have gone on the gluten-free diet without celiac disease testing. “We have to find a way to find celiac disease in those who are already gluten-free,” he said. Meanwhile, Govind Makharia, M.D., of the All India Institute of Medical Sciences in New Delhi, put the global prevalence of celiac disease at about 1 percent, the same rate found in the United States.
A Swedish study that looked gender and quality of life found that women with celiac disease struggle more than men, said Claes Hallert, M.D., of Linkopings Universitet. Women who had been on the gluten-free diet for 10 years reported isolation, fear of cross-contact, worries about being a bother, shame and a desire to be more secure when eating outside the home. “We have to redefine remission to include quality of life,” Hallert said.
Whether beer can be included in the gluten-free diet varies around the world. Markku Maki, M.D. of the University of Tampere, Finland and Frits Konig, Ph.D., of Leiden University Medical Center, the Netherlands, led a lively discussion about the safety of beer. Sweden had long allowed beer while Finland did not.
“Gentlemen began to write to us to say we want to be as free as the Swedish,” Maki said. Finnish breweries started to develop safer beer and in 2005 the Finnish Celiac Society allowed the inclusion of beers with the gluten-free symbol to be included on the gluten-free diet. Konig said Dutch beers “are very clean and lagers have 20 parts per million or 25 parts per million of gluten. “In that sense, you can relax,” he said.
While Maki and Konig indicated most lagers are safe, only beer that is made from gluten-free grains is allowed on the gluten-free diet in the United States.
Patient data and participation key
Researchers’ need for data about celiac disease patients in the United States continues to be unmet, according to Ben Lebwohl, M.D., director of clinical research in the Celiac Disease Center at Columbia University. Unlike other countries, there are no national registries that keep track of patients over long periods of time. This makes it difficult for researchers to compile information, Lebwohl said.
Some scientists rely on insurance-claims-based research, but this leaves many gaps. Beyond Celiac is beginning to meet the need through the development of its patient registry, Go Beyond Celiac. Registries created by groups like Beyond Celiac provide a large sample size, are geographically diverse and patient-centered, Lebwohl said. However, researchers have some concerns, including whether those who are willing to share information in a registry are somehow different from those who don’t, reliance on patient self-reporting and retention of registry members. He concluded that multiple sources of data are important.
The current picture of celiac disease is largely based on two types of patient, those who are health conscious and well and those who have complicated cases of celiac disease and are not well, according to Daniel Leffler, M.D., medical director, clinical science, gastroenterology, Takeda Pharmaceuticals, USA Inc. These are the patients who are usually seen at celiac disease centers or are otherwise seeing physicians for follow-up care.
“The 95 percent in between is in a black box,” Leffler said. Both he and Murray noted it’s important to get a more complete picture of celiac disease patients.
While researchers who spoke at the symposium covered a lot of what is known about celiac disease, Lebwohl concluded the patient presentations by addressing what isn’t known. How to prevent celiac disease or how to stop it in its tracks topped his list. Other topics included: the degree of precautions patients need to take to avoid cross-contact, who to screen for celiac disease, why patients’ symptoms are so variable and which drug holds the most promise for treatment. Participation in clinical trials was urged as one of the most important steps patients can take to help scientists answer outstanding questions.