A remote controlled drug delivery capsule for use in absorption studies has been developed by a UK company. The new technology, called the Enterion capsule, is being used by Pharmaceutical Profiles, an early phase development company. It was developed by Phaeton Research, a sister company to Pharmaceutical Profiles.
The capsule is designed to release drug at an exact target site in the gastrointestinal tract. Researchers can then measure the extent to which the drug is absorbed from different regions of the GI tract.
The capsule is activated by a radiofrequency signal, which releases a spring-controlled piston and leads to release of the capsule contents (see Figure). The location of the capsule within the GI tract is tracked using gamma scintigraphy while the presence of a radiolabel within the drug reservoir allows visualisation of the drug in the GI tract following activation. The empty capsule is excreted.
Dr Ian Wilding (chief executive, Pharmaceutical Profiles) said recently that many candidate drug molecules currently being developed had complex chemistry, poor solubility and limited permeability, which led to problems of delivering the drugs effectively to patients. Traditional studies to measure absorption profiles tended to be carried out on products that were already formulated and the chosen formulation could turn out not to be ideal. With the new technology, which could test particulates and liquids, decisions on optimal drug delivery technology, or on whether the oral route was perhaps not suitable after all, could now be taken before too much time had been spent on formulation development. "The information produced by Enterion will assist in ensuring that rational and effective decisions are made during the early clinical development of candidate molecules," Dr Wilding said.

A radiofrequency signal releases a spring-controlled piston and the movement of the piston barrel initiates rapid release of capsule contents into the target area. The capsule is 32mm long