GlaxoSmithKline says a potential heart disease treatment it acquired as part of a key 2012 company takeover fell short in the main measurement of a late-stage study.
The British drugmaker says darapladib failed to produce a statistically significant reduction in major cardiovascular events like heart attacks, strokes or death when added to a patient's standard of care. More than 15,000 patients enrolled in the international study of adults with chronic coronary heart disease.
GlaxoSmithKline says the study results are preliminary. It will wait for results from a separate late-stage study before deciding what to do next.
The pharmaceutical company acquired the experimental treatment when it bought drug development partner Human Genome Sciences for more than $3 billion.
U.S.-traded shares of GlaxoSmithKline are down 2 percent in premarket trading.