In its first year of commercial use, the swallowable, gas-filled, three-balloon weight loss device (Obalon, Obalon Therapeutics) demonstrated a good safety record and resulted in greater weight loss than seen in the pivotal randomized trial leading to its US approval, new data show.

Safety and efficacy results from more than 1300 patients at over 100 sites in Obalon’s voluntary registry were presented recently at Obesity Week 2018, according to a media release from Medscape.

Approved by the US Food and Drug Administration (FDA) in 2016, the Obalon Balloon System consists of three balloons that are delivered to the stomach via a capsule that the patient swallows. Once in place, the balloons are inflated with attached microcatheters and left in for 6 months, after which they are retrieved endoscopically. The system is indicated for patients with a body mass index (BMI) of 30 to 40 kg/m2 with or without obesity-related comorbidities.

The registry, in which prescribing physicians enter weight loss and safety data, was launched when the Obalon Balloon System became available in January 2017.

The registry included a total of 1343 patients who swallowed one or more of the gas-filled balloons over a years’ time at 108 US centers. Patients were a mean age of 46 years, 79% were women, and 67% were white.

Mean BMI was 35.4 kg/m2, but 17% had BMIs above the indicated range (> 40 kg/m2), and 12.5% had BMIs below the range (25.1 to 29.9 kg/m2).

Most of the patients (88%) had swallowed all three balloons, with median administration times of second and third balloons at 2.6 and 7.4 weeks after the first one.

Another 9% received just two balloons, and 3% had only one. A majority (82%) kept the balloons in for the entire recommended 6 months, the release explains.

Out of a total of 3818 balloons administered in the registry, deflations occurred in just 0.18% and failure to inflate in 0.13%.

There were no deaths or unanticipated adverse device effects. Two (0.14%) serious adverse device effects were reported — a gastric perforation and dehydration requiring hospitalization and balloon removal — neither had permanent sequelae.

The most common adverse events were abdominal pain and nausea, both each in about 5% of patients, vomiting in 2%, and abdominal distension in 1%.

Overall weight loss was 9.6 kg for the 1177 patients who had three balloons, compared with 6.6 kg and 3.1 kg, respectively, for those with two and one balloons. Total body weight loss was 9.6%, 6.9%, and 3.4%, respectively.

Comparing results at 22 weeks for 787 registry patients with those of the pivotal trial involving 174 participants, weight loss was 9.7 kg versus 7.1 kg, and total percent body weight loss was 10.0% vs 7.1%, per the release.