Researchers in Singapore have developed EndoPil, a self-inflating weight-control pill that overcomes the limitations associated with endoscopically administered intragastric balloons.
Designed by a team led by Prof Louis Phee, Dean of Engineering at Nanyang Technological University (NTU), and Prof Lawrence Ho, a clinician-innovator at National University Health System (NUHS), the EndoPil could provide a non-invasive alternative to tackle obesity.
Measuring around 3cm by 1cm, the EndoPil is said to have an outer gelatine casing that contains a deflated balloon, an inflation valve with a magnet attached, and a harmless acid and a salt stored in separate compartments in an inner capsule.
EndoPil is designed to be taken orally with water. According to NTU, acid in the stomach breaks open the outer gelatine casing of the capsule, and its location in the stomach is ascertained by a magnetic sensor. An external magnet measuring 5cm in diameter is used to attract the magnet attached to the inflation valve, opening the valve. This mechanism avoids premature inflation of the device while in the oesophagus, or delayed inflation after it enters the small intestine.
The opening of the valve allows the acid and the salt to mix and react, producing carbon dioxide to fill up the balloon, which then floats to the top of the stomach, the portion that is more sensitive to fullness. The ingredients were chosen as a safety precaution to ensure that the capsule remains harmless upon leakage, said Prof Phee.
The balloon can be inflated to 120ml in three minutes and be deflated magnetically to a size small enough to enter the small intestines.
Currently, moderately obese patients and those who are too ill to undergo surgery can opt for the intragastric balloon, a weight loss intervention that is inserted into the stomach via endoscopy under sedation, a procedure that isn’t suited to all patients.
It is also common for patients who opt for the intragastric balloon to experience nausea and vomiting, with up to 20 per cent requiring early balloon removal due to intolerance. The stomach may also get used to the prolonged placement of the balloon within, causing the balloon to be less effective for weight loss. EndoPil could overcome these limitations.
Prof Phee said, “EndoPil’s main advantage is its simplicity of administration. All you would need is a glass of water to help it go down and a magnet to activate it. We are now trying to reduce the size of the prototype and improve it with a natural decompression mechanism. We anticipate that such features will help the capsule gain widespread acceptance and benefit patients with obesity and metabolic diseases.”
In a pre-clinical trial, a larger version of EndoPil was inserted into a pig, which lost 1.5kg in a week. Last year, the team conducted a trial of their capsule on a healthy patient volunteer in Singapore, with the capsule inserted into the patient’s stomach through an endoscope. The balloon was successfully inflated with no discomfort or injury from the inflation.
The team hopes to conduct another round of human trials in a year’s time. In the interim, the team will present its latest findings at Digestive Disease Week 2019 in San Diego.