By Ben Hirschler
LONDON (Reuters) - Europe's medicines regulator has written to AstraZeneca asking it to provide more information about a U.S. probe into a clinical trial of the company's new heart drug Brilinta.
AstraZeneca is relying on Brilinta as a key driver of near-term sales and profit growth, and the unusual decision by the U.S. Department of Justice (DOJ) to launch an investigation has raised concerns about the product's future.
The London-based European Medicines Agency (EMA) said on Thursday that it contacted Britain's second biggest drugmaker earlier this week after the DOJ probe was disclosed by the company on October 31.
"The EMA takes seriously any information that may have an impact on the profile of a drug's benefits and risks," spokeswoman Monika Benstetter said in response to a Reuters inquiry.
"At the moment we are at the point of trying to understand what is going on," she added.
The 18,000-patient study used to win marketing approval in 2011 had already been criticized by some medical experts who questioned the way it was conducted.
AstraZeneca spokeswoman Ayesha Bharmal said the company had informed the EMA and other regulators of the DOJ's civil investigative demand but could not comment further.
Brilinta sales have disappointed since its launch two years ago, although AstraZeneca has recently stepped up marketing efforts and hopes that further clinical tests will underscore its value in preventing heart attacks.
AstraZeneca CEO Pascal Soriot said last week he was "very confident" in the findings of the pivotal clinical trial, known as PLATO, noting it was led by "a strong academic group".
Neither the drugmaker nor the DOJ have disclosed the exact nature of the investigation, but analysts believe it likely relates to various aspects of the study that have been criticized by outside researchers.
James DiNicolantonio of Ithaca New York and Ales Tomek of Charles University in Prague, for example, said in a recent paper that patients in the trial monitored by AstraZeneca were reported as benefiting more from taking Brilinta than those monitored by an independent clinical research organization.
Bernstein analyst Tim Anderson said in a research note this week there could be material downside for AstraZeneca if the DOJ investigation revealed serious flaws in the study.
Brilinta's progress to date has been slow, with sales in the third quarter edging up to just $75 million from $65 million in the three months to end-June - a long way from the multibillion-dollar potential analysts predicted at its launch.
(Editing by Elaine Hardcastle)