CORRECTED - CORRECTED-(May 13)-UPDATE 3-Medicines Co stops anticlotting tria

(Corrects paragraph 16 in May 13 story to clarify that the company could, and not would, retain pediatric exclusivity till September 2010)

* Co ends late-stage trial of anti-clotting agent

* Shares down as much as 45 percent

* Wedbush raises stock to buy, Leerink cuts target

(Recasts, adds analysts' comments and updates share movement)

By Shailesh Kuber

BANGALORE, May 13 (Reuters) - Medicines Co (MDCO.O) pulled the plug on the development of an experimental treatment to prevent blood clotting during angioplasty as it is not expected to meet its main trial goal, sending the stock crashing as much as 45 percent.

However analysts said the sell-off was overdone as the drug developer had other promising candidates, and the stock fall could prove attractive to would-be acquirers.

"If Medicines remains at its current value of about $6-$7 per share, we believe the company could be an attractive take-out candidate for big pharma or other companies with sales in acute care," Wedbush analyst Liana Moussatos said.

Shares of the company, the biggest percentage loser on Nasdaq Wednesday, closed down 37 percent at $7.02. They hit a more than seven-year low of $6.15 earlier in the day.

Medicines discontinued late-stage trials of the antiplatelet agent cangrelor in patients undergoing procedures to widen narrowed arteries, as the intravenously administered drug showed no real difference in effectiveness compared with the oral drug Plavix.

Discontinuation of the program will result in cost savings of about $5 million in 2009, the company said.

Antiplatelets like Bristol-Myers Squibb Co's (BMY.N) and Sanofi-Aventis SA's (SASY.PA) blockbuster Plavix work by stopping platelets -- tiny blood cells vital for the normal clotting process -- from clumping together and forming life-threatening clots in arteries.

Plavix has annual sales of around $8 billion.

Medicines said it will now accelerate development of cangrelor as a replacement for Plavix in patients requiring cardiac surgery but cannot take that drug due to a risk of bleeding.

Cangrelor was licensed from AstraZeneca (AZN.L) in December 2003.

STOCK OVERSOLD

"We believe it is not game over for Medicines Co. Cangrelor may work as a bridge to cardiac surgery and Oritavancin may be successful as an acute care antibiotic," Wedbush's Moussatos said.

Oritavancin is the company's antibiotic candidate for the treatment of infections such as the deadly MRSA.

She raised the Medicines stock to "buy" from "hold" saying the stock was oversold on reaction to cangrelor.

Moussatos projected peak annual sales of about $70 million for Cangrelor if the alternate indication was successful and estimated peak annual sales of about $100 million for Oritavancin.

In reiterating his "outperform" rating on the stock, Leerink Swann analyst Joseph Schwartz said the market was not accurately valuing the opportunity of Angiomax, an anti-coagulant already marketed by the company for use in patients undergoing coronary angioplasty.

Angiomax, which goes off patent in March 2010, but for which the company could retain pediatric exclusivity till September 2010, had U.S. sales of $334.2 million in 2008.

"After patent exclusivity ends, we believe Angiomax will only have a limited number of generic threats given the extremely difficult manufacturing process, which will encourage more rational generic pricing," Schwartz said in a note.

He however cut his fair value estimate on the stock to $11 from $20 due to removal of cangrelor from the brokerage's model.

(Editing by Aradhana Aravindan, Anthony Kurian)