A swallowable, vibrating capsule improved symptoms among patients with chronic idiopathic constipation in a phase 3 multicenter, randomized, controlled trial. The method represents a mechanical approach to the treatment of constipation.
The swallowable pill acts by vibrating during passage through the gut, where it is thought to augment colonic biorhythm and peristalsis. Traditional treatments for constipation generally increase motility or secretion.
“That’s how we have been managing constipation since time immemorial. Now we have come up with this novel approach, where there’s a pill that is designed to increase local oscillations, and probably induce local contractions of the colon to mimic what happens normally,” said Satish Rao, MD, PhD, who presented the results of the trial at the annual Digestive Disease Week® (DDW).
“We’re now seeing that local stimulation works, and the other neat thing seems to be a lack of side effects, which is really a huge plus. I think it will benefit people with both occasional or chronic constipation,” said Dr. Rao, professor of medicine at Medical College of Georgia, Augusta.
The capsules activate for two stimulation cycles, each lasting for about 2 hours. The cycle includes 3 seconds of vibration followed by 16 seconds of rest.
The researchers conducted a study with two active arms and a placebo. It included 312 patients age 22 or older who had an average of between 1 and 2.5 spontaneous bowel movements (SBM) per week.
Treatment lasted for 8 weeks, with patients ingesting a capsule between 9 and 10 p.m. In one treatment group, the device was activated at 6 a.m., and in the other group at about 2 p.m.
The placebo and treatment groups had similar baseline characteristics, except for a longer duration of constipation in the treatment groups (17.9 versus 14.5 years; P = .0253). In an intention-to-treat analysis, the treatment groups were more likely to achieve an increase of one complete SBM per week (39.26% versus 22.15%; P < .0001) and an increase of two complete SBMs per week (22.7% versus 11.41%; P < .0006).
The capsules also improved straining score, stool consistency, and quality of life. There was no significant difference between treatment and placebo groups with respect to bloating or rescue medication use.
The product had few adverse effects. The most common was a vibrating sensation or discomfort (11.0%, versus none in the placebo group).
Dr. Rao expects that the treatment could be widely applicable since many constipation patients don’t gain sufficient benefit from existing treatments, or find side effects intolerable.
Another benefit is that the therapy’s mimicry of natural cycles appears to grant patients more control of bowel movements. Laxatives and other pharmaceutical interventions may prompt the patient to go to the bathroom within an hour or two, but patients in the trial reported bowel movements at predictable times.
However, he noted that the pill is nondissolvable, which would make it contraindicated for patients who have had previous gut surgeries or narrowing of the gut. He noted that the sponsoring company, Vibrant Gastro, expects to obtain Food and Drug Administration approval by the end of 2022.
The results of the study were well received. “I think it’s an exciting new approach for managing patients with chronic constipation. It was a large sample size, and the treatment seems to be well tolerated. It may offer a promising option for patients who have not responded to many other medications,” said Adil E. Bharucha, MD, who comoderated the session where the research was presented.
However, he pointed out that the presentation did not indicate how many of the patients had previously tried other therapies. “We’d like to see the full paper, which will provide a better understanding of the role of this treatment in practice down the road,” said Dr. Bharucha, professor of medicine in the division of gastroenterology and hepatology and director of the office of clinical trials at Mayo Clinic, Rochester, Minn.
The capsule may not work for everyone, said Dr. Bharucha. He suspects that many refractory patients have an issue with pelvic floor muscles, which may restrict stool evacuation. “You wouldn’t expect those people to respond optimally to a laxative and I suspect perhaps not to a capsule, either. I think defecatory disorders are substantially underdiagnosed in patients who don’t respond to laxatives,” said Dr. Bharucha.
Asked why the capsule might benefit patients who don’t improve with laxatives, Dr. Bharucha responded: “I think we need more studies to understand how the capsule works.”
Dr. Rao consults for Vibrant Gastro. Dr. Bharucha has no relevant financial disclosures.