* Company has appointed banks for IPO
* Company tried to float in 2011
* Previous valuation was 90-140 mln eur (Adds chief executive comments on valuation)
BRUSSELS, June 4 (Reuters) - Belgian heart drug specialist Cardio3 BioSciences is planning a stock market flotation in Brussels and Paris, it said on Tuesday, without giving details on the timing or size of the issue.
The company, a specialist in stem cell treatments for heart problems, has appointed investment bank Kempen & Co as sole global coordinator for the issue. Joint bookrunners are Kempen & Co and Invest Securities.
Cardio3 tried unsuccessfully to float in 2011.
"The financial markets were particularly difficult during that period, demonstrated by the lack of IPOs (initial public offerings) on the Brussels stock exchange after that date," a company spokesman said.
The company had been valued at between 90 million euros ($117.6 million) and 140 million in that flotation attempt, Cardio3 Chief Executive Christian Homsy said.
A banker with knowledge of the sector, who spoke on condition of anonymity, said the IPO was unsuccessful because investors were not willing to pay the price asked. But Homsy said the key issues were the fact that the company had not begun Phase III trials, combined with difficult markets at the time.
"Never, ever the price was mentioned as an issue," he said.
Belgium has not had a significant IPO since biotechnology firm Movetis at the end of 2009.
The planned flotation follows an announcement last month by Belgium's postal operator bpost that it will list a minority stake, currently held by private equity group CVC Funds , on the Brussels stock exchange.
Cardio3 has a large-scale trial running in Europe for C-Cure, its treatment for heart failure which involves taking cells from a part of the patient's body that has the ability to repair itself, and then treating the cells to become heart cells and injecting them into the heart.
($1 = 0.7675 euros) (Reporting by Ben Deighton; Editing by Robert-Jan Bartunek and Mark Potter)