There was disappointment for US drugmaker Eli Lilly yesterday, after it revealed that its osteoporosis drug Evista had failed to decrease the risk of heart disease in a large-scale study.

There had been high hopes that the labelling for Evista (raloxifene), a selective oestrogen receptor modulator, could be extended to include protection against heart attacks after earlier studies showed that it could achieve a reduction in low-density lipoprotein (LDL) cholesterol.

But results from the RUTH trial found no such benefit, although Evista did lower the risk of breast cancer in women taking it. The study involved 10,000 post-menopausal women who took raloxifene or placebo daily and were followed for seven years. All either had heart disease or were at a high risk of a heart attack.

"Because Evista did not prevent coronary events, we want to reinforce for physicians that Evista should not be prescribed for cardioprotection," said Lilly chief medical officer Alan Breier in a statement.

In December, Lilly was fined $36 million by the US government for promoting Evista for off-label uses, including cutting the risk of breast cancer and heart disease.

Evista has been a nice earner for Lilly, racking up sales of a little over $1 billion last year as an osteoporosis treatment, but has seen its sales growth trimmed back in the face of increased competition in the sector, with a raft of new osteoporosis drugs due to reach the market over the coming years.

One factor behind Evista’s slowing growth is that its effects on bone mineral density are not as strong as rival drugs, such as the bisphosphonates, which lead the osteoporosis treatment market.

To bolster the product, Lilly has been trying to extend the labelling of Evista to show benefits across a broad range of conditions that affect post-menopausal women. For example, another 19,000-patient clinical trial comparing Evista to the anti-oestrogen drug tamoxifen in breast cancer, called STAR, is due to report data in the next few weeks.

Evista already has approval in 18 countries around the world for reducing breast cancer risk and, if the STAR results are positive, Lilly has said it plans to file for approval of a breast cancer indication for Evista in the USA later this year. However, Prudential analyst Tim Anderson said in a research note he does not think approval in breast cancer will be a significant new revenue stream for the drug.