Trial in Texas Testing IVIG Enrolling Sjögren’s Patients With POTS
A clinical trial at the University of Texas Southwestern Medical Center in Dallas is currently recruiting people with autoimmune diseases, particularly Sjögren’s syndrome, who also have postural orthostatic tachycardia syndrome (POTS).
The study, supported by a $150,000 joint grant from the Sjögren’s Foundation and Dysautonomia International, is testing the efficacy of intravenous immunoglobulin (IVIG), an immune-suppressing treatment.
POTS refers to an inappropriate increase in heart rate (typically 30 beats per minute or more in adults) when a person stands up, accompanied by symptoms such as dizziness, lightheadedness, or feeling faint. POTS is a form of dysautonomia — when the autonomic nervous system, which controls heart rate and other bodily processes beyond conscious control like digestion, does not work properly.
According to Steve Vernino, MD, PhD, a neurologist and director of the Autonomic Disorders Clinic at UT Southwestern and the trial’s lead researcher, people with autoimmune diseases like Sjögren’s may be at increased risk of POTS and other forms of dysautonomia, because there is a “close relationship between the autonomic nerves and the immune system,” with each affecting the other.
The basic idea is that people with autoimmune diseases have irregular inflammation, which could interfere with autonomic nerves and cause irregularities in the body’s stress response, Vernino said in a foundation release with an accompanying video. Supporting this idea, people with POTS often have abnormal antibodies or autoimmune diseases, and the presence of POTS in Sjogren’s disease patients is “probably the most recognized association.”
Vernino noted that his clinic screens POTS patients for potential Sjogren’s, asking them, for example, about common symptoms like dry eyes or mouth.
The ongoing clinical trial is a double-blind crossover study: participants will be randomly given a first infusion of IVIG or a placebo and assessed for symptom response. Then, in the second round of infusions, those initially assigned to placebo will get IVIG, and vice versa. After both rounds, symptoms and other markers of disease will be assessed to determine the effect of treatment.
The study is currently enrolling new participants, and the researchers are “particularly interested in enrolling patients who have Sjögren’s disease,” Vernino said.
Sjögren’s patients who know or suspect they have POTS can email [email protected] for more information.
“A hint that you might have POTS, and that you should get screened for it, is if you have frequent lightheadedness when you stand up [and] a racing heartbeat when you stand up,” said Lauren Stiles, the president of Dysautonomia International, who is a Sjögren’s patient living with POTS.
Due to practical considerations — the study requires two visits for infusions, plus a number of other clinical visits — participation is mainly limited to people who live in or near Dallas. Also of note, the study is not open to patients who are currently being treated with biologics such as rituximab.
“Research is all about learning and it is a long, long game,” said Janet Church, president and CEO of the Sjögren’s Foundation. “The more we start learning now about POTS and Sjögren’s, the better.”