French drugs maker Sanofi-Aventis SA (SNY) is in exclusive talks with U.K.-based Covance Inc. (CVD) for the sale of research facilities located in Porcheville, France and Alnwick in the U.K.

The companies have signed a non-binding memorandum for the sale which could take place before the end of the year after consultation with works councils. The sale would entail the transfer of around 300 employees.

The sites cover preclinical drug development including chemistry, manufacturing and drug safety assessment. The sites were flagged for divestment last year as part of Sanofi-Aventis' overhaul of its research and development activities.

-By Mimosa Spencer, Dow Jones Newswires; +33 1 40 17 17 73; mimosa.spencer@dowjones.com