$3.9 billion was wiped off Sepracor's market capitalization as investors called into question the entire utility of single enantiomers as a means of improving drugs and managing product life cycles.

Eli Lilly & Co. (Indianapolis, IN) is fighting to protect $3 billion annual sales of its selective serotonin re-uptake inhibitor, Prozac (fluoxetine). In a $4 million settlement in January, Lilly ...