GlaxoSmithKline has suffered a setback after the closely-watched heart drug darapladib failed to meet its primary endpoint in the first of two late-stage trials.
The drugs major has announced top-line results from the Phase III STABILITY trial evaluating darapladib, an investigational Lp-PLA2 inhibitor, in adults with chronic coronary heart disease. The study did not meet the primary endpoint, which was time to first occurrence of any major adverse cardiovascular event from the composite of myocardial infarction (heart attack), stroke, and cardiovascular death.
However, GSK noted that there were greater reductions in some secondary endpoints "that require further analysis". Frequently reported adverse events included diarrhoea and odour which occurred at a similar frequency to that seen in Phase II. Further analysis of the data is ongoing and full results will be presented at a scientific meeting in 2014.
Patrick Vallance, president of pharmaceuticals R&D at GSK, said that “given the level of patient need in this area, we continue to investigate the role of Lp-PLA2 inhibition in coronary heart disease and other diseases". He added that "we will now work to better understand the data, including evaluation of the patient sub-groups, and await the outcome of a second Phase III study of darapladib in acute coronary syndrome, called SOLID-TIMI 52, to determine our next steps".
Observers fear the worst and Panmure Gordon analyst Savvas Neophytou has downgraded GSK to 'hold' from 'buy' following the news. He noted that even if the second Phase III study is successful (results are expected in the first half of 2014), "we believe it will be difficult to gain market registration on one trial alone."