What happened

Shares of Radius Health (RDUS 0.54%), a biopharmaceutical company, are soaring today in response to positive clinical-trial data. Investors excited about elacestrant, an experimental new cancer treatment Radius Health is developing in partnership with the Menarini Group, an Italian company, pushed the stock up 48.8% shortly after the market opened. The stock was still up 34.6% as of 11:25 a.m. EDT on Wednesday.

So what 

Elacestrant is an experimental therapy for breast cancer patients who have tumors that express lots of estrogen receptors but lack receptors for human epidermal growth factor. In the phase 3 Emerald trial with ER+/HER- patients, treatment with elacestrant significantly reduced the risk of death or worsening disease.

Investor looking at a rising stock chart.

Image source: Getty Images.

Elacestrant is a potential first-in-class selective estrogen receptor degrader (SERD). Luckily, it provided a progression-free survival benefit for the overall population and not just the group of patients with tumors that harbor estrogen receptor 1 mutations. 

This is a big deal for Radius Health because sales of its lead product, Tymlos, have been somewhat disappointing. The osteoporosis drug reduced patients' long-term risk of vertebral fractures by 87% during trials leading to its approval in 2017. Sales of the daily injection, though, still aren't strong enough to make ends meet.

Now what

Today's news is a step in the right direction, but Radius Health still hasn't shared the important details. The biotech company will present in-depth results from the Emerald study at the San Antonio Breast Cancer Symposium scheduled for this December. 

Radius Health finished June with about $100 million in cash after burning through $33 million in the first half of 2021. Unfortunately, the losses will likely continue. Revenue from Tymlos fell to $97 million from $98 million in the first half of 2020.