Pistorius' career on the track suffered a setback in 2009 when he suffered serious head injuries in a boating accident.

CNN: February 14, 2013 -- Updated 1700 GMT (0100 HKT)

Iraq's official nuclear program was dealt a setback in 1981, when a reactor it was building in Osirak was destroyed in a raid by the Israeli air force.

CNN: Iraqi nuclear scientist surrenders to U.S. troops

Beleaguered Guidant, whose stock price has fallen 30% year to date and more than 6% today, suffered a setback in March when its in-house drug-coated stent proved ineffective in clinical trials.

FORBES: Guidant Loses Big