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           CLINTRIALS RESEARCH ANNOUNCES DEFINITIVE MERGER AGREEMENT

FOR IMMEDIATE RELEASE

     RESEARCH TRIANGLE PARK, NC, FEBRUARY 22, 2001 -- ClinTrials Research, Inc.
(NASDAQ: CCRO) ("ClinTrials") and Indigo Acquisition Corp. ("Indigo") announced
today that they have entered into a definitive merger agreement for Indigo to
acquire all of the outstanding shares of ClinTrials for $6.00 per share in cash.

     Under the terms of the agreement, Indigo will commence a tender offer for
all of the outstanding shares of ClinTrials at $6.00 per share within seven
business days. The tender offer will be subject to at least a majority of the
outstanding ClinTrials shares, on a fully diluted basis, being validly tendered
and not withdrawn. The tender offer will also be subject to regulatory approvals
and other customary conditions. Any ClinTrials shares not acquired pursuant to a
successful tender offer will be acquired in a subsequent merger at the same
$6.00 per share cash price.

     In connection with the execution of the merger agreement, Indigo has
entered into an agreement with the holders of approximately 21% of ClinTrials
outstanding shares under which such holders have agreed to tender their shares
in the tender offer.

     ClinTrials is a global contract research organization headquartered near
Research Triangle Park, North Carolina with offices in Maidenhead, England;
Glasgow, Scotland; Montreal, Canada; Brussels, Belgium; Paris, France;
Melbourne, Australia; Tel Aviv, Israel; Milan, Italy; Warsaw, Poland; Madrid,
Spain; and Munich, Germany. With more than 1,500 employees, ClinTrials provides
comprehensive research services, including monitoring, data management and
biostatistics, medical and regulatory services to pharmaceutical, biotechnology
and medical device clients.

     Paul Ottaviano, Chief Executive Officer of ClinTrials said, "We are very
pleased with this transaction from the perspective of shareholders. We believe
the combination with Indigo will allow the combined company to maximize its
potential in offering contract research services".

     Indigo is a private, wholly-owned subsidiary of Inveresk Research Group
Limited ("Inveresk"). Headquartered near Edinburgh, Scotland, Inveresk is a
leading European provider of contract research services, primarily to the
pharmaceutical and biotechnology industry.

     Dr. Walter Nimmo, Chief Executive Officer of Inveresk, said today, "We are
excited by the opportunity offered by the merger of Indigo and ClinTrials. The
businesses are complementary. The combination represents a key step in the
building of Inveresk's clinical trials business on a world-wide basis".

     ClinTrials will announce later today its results for the fourth quarter and
full year ended December 31, 2000.

     This release includes certain forward-looking statements that are based
upon the belief of the management of ClinTrials, Indigo and Inveresk. These
forward-looking statements are subject to a number of risks and uncertainties,
including but not limited to the possible inability of Inveresk to complete the
acquisition of ClinTrials. These uncertainties are in addition to the risk
factors detailed in the Company's Securities and Exchange Commission filings and
in the earnings press release.

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     THIS ANNOUNCEMENT IS NEITHER AN OFFER TO PURCHASE NOR A SOLICITATION OF AN
OFFER TO SELL SECURITIES OF CLINTRIALS. AT THE TIME THE OFFER IS COMMENCED,
INDIGO WILL FILE A TENDER OFFER STATEMENT (INCLUDING RELATED TENDER OFFER
DOCUMENTS SUCH AS AN OFFER TO PURCHASE AND A FORM OF LETTER OF TRANSMITTAL FOR
SHAREHOLDERS OF CLINTRIALS) WITH THE SEC, AND CLINTRIALS WILL FILE A
SOLICITATION/RECOMMENDATION STATEMENT WITH THE SEC. THESE DOCUMENTS WILL CONTAIN
IMPORTANT INFORMATION ABOUT THE OFFER AND SHAREHOLDERS OF CLINTRIALS ARE URGED
TO READ THESE DOCUMENTS BEFORE MAKING A DECISION ABOUT THE OFFER. IN ADDITION,
THE DOCUMENTS FILED BY INDIGO WILL BE AVAILABLE FREE OF CHARGE FROM THE SEC'S
WEBSITE AT WWW.SEC.GOV.

CONTACT:

GCI
Christopher Gordon
(212) 886-3428

ClinTrials Research, Inc.
Paul Ottaviano
Chief Executive Officer
(919) 460-9005

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