UK contract research organisation Xceleron has announced a major expansion of its activities in the USA in order to tap into what it believes will be growing market for its microdosing capabilities.

Microdose or Phase 0 studies involve the testing of trace doses of drugs are tested in humans to evaluate pharmacokinetics and drug metabolism before they enter Phase I trials. The aim is to speed up drug discovery, identify failures sooner and cut study costs by weeding out candidates with short half-lives or poor bioavailability.

Xceleron has pioneered the use of accelerator mass spectrometry in microdosing, and as part of its US expansion has just purchased a second AMS system that will operate at a testing facility in Maryland. The new facilities are due to come on line in late 2007 and, by 2011, the company expects to be employing 150 staff in the USA with North American revenues of more than $20 million.

The company is expecting a hike in interest in the use of microdosing to provide a rapid, safe evaluation of new drug candidates to get a boost from the recent publication of data from the Consortium for Resourcing and Evaluating Microdosing (CREAM) study.

CREAM, sponsored by drugmaker such as Eli Lilly, Roche, Servier and Schering, was designed to prove that microdosing truly does give an accurate reflection of the pharmacokinetic parameters of a compound by comparing micro and pharmaceutical doses.

The drugs are already on the market but have one other key characteristic in common – all had complex metabolic properties which meant that animal studies or in vitro studies were unable to predict pharmacokinetics in humans. The study found that, even in these difficult cases, microdosing studies were about 70% effective in predicting the behaviour of the drugs under test.

The company is particularly hoping that CREAM will help accelerate take-up of microdosing studies in the USA, which has been lagging behind Europe in the adoption of the technology, and drive demand for services at Xceleron’s new Maryland facilities.

Colin Garner, Xceleron's chief executive, said: "the CREAM results ... represent a surprise to some in the pharmaceutical community as the predictive value of microdosing worked in circumstances that were cited as being unlikely for microdosing to succeed."

Also stimulating the take-up of microdosing in the USA is the publication by the Food and Drug Administration of the Exploratory Investigational New Drug guidance, which for the first time laid out the agency’s thinking on how Phase 0 studies should be conducted and, crucially, reviewed as part of a drug marketing application dossier.