Study shows Glaxo heart drug which failed trial has potential benefit

WASHINGTON, March 30 (Reuters) - An experimental heart drugbeing developed by GlaxoSmithKline, which failed themain goal of a Phase III study of patients with chronic butwell-treated heart disease, showed signs of potential benefit,the trial's co-leader said Sunday.

The results presented at the American College of Cardiologyscientific meeting in Washington provided a glimmer of hope thatthe medicine may have value.

"I'm convinced there is a signal here of efficacy," said Dr.Harvey White, co-chair of the Glaxo-sponsored internationalstudy.

The real test of the drug, darapladib, is likely to comefrom a second, late stage study in far less stable patients whoreceived the medicine within 30 days of a heart attack.

A positive result in that study could put the drug back ontrack, after it was largely discounted by analysts and investorsfollowing the first Phase III failure.

The stakes are high for the British drugmaker as gainingfull control of darapladib was one of the reasons behind its$3.6 billion acquisition of Human Genome Sciences in 2012.

Human Genome had rejected an earlier $2.6 billion offer, onthe grounds that Glaxo was underestimating the blockbuster salespotential of darapladib.

Glaxo had previously said darapladib did no better than aplacebo in decreasing the risk of a combination ofcardiovascular death, heart attack and stroke in the trialcalled Stability.

That trial involved 15,828 patients followed for a median of3.7 years.

For those taking the Glaxo pill, 9.7 percent had one of themajor adverse events compared with 10.4 percent for placebo,which was not a statistically significant difference.

A lack of any impact on stroke prevention appears to havecontributed to the failure of the study, researchers surmised.

In addition, the effect of the Glaxo drug may have beenmuted by the high level of care the patients were receiving.

Almost all were taking statins and aspirin and nearly 80percent were on blood pressure drugs - all known to decrease therisk of heart attacks, strokes and death.

The drug's impact on a pair of composite secondary goals ofthe study was deemed "nominally significant" by researchers,meaning they saw the potential of a clinically meaningful effectdespite falling short of statistical significance. (Reporting by Bill Berkrot; Editing by Sophie Hares)