Perhaps healthier hearts? http://www.fda.gov/Drugs/DrugSafety/ucm341822.htm http://www.fda.gov/Drugs/DrugSafety/ucm341822.htm Seems like one of the primary fe

Perhaps healthier hearts? http://www.fda.gov/Drugs/DrugSafety/ucm341822.htm http://www.fda.gov/Drugs/DrugSafety/ucm341822.htm Seems like one of the primary features of this antibiotic was to have a chemical that was new at the time, so patent protection could be enjoyed from that point forward. Different features can have different priorities at different times, sometimes there's nothing "engineering" can do about it, it's a marketing thing. Wherever cardiac health might fall on the priorities list, it's probably not way up there for this compound. disclaimer: haven't worked for a drug producer since I was first out of college