CNN  — 

Covid-19 vaccines are on everyone’s mind, including investors in pharmaceutical and biotech stocks.

But while Pfizer (PFE), BioNTech (BNTX) and Moderna (MRNA) are making headlines – and money – several smaller drug companies are generating attention for work they are doing to combat another deadly disease: breast cancer, the second most common cause of death from cancer in women in the US.

Several biotechs’ stocks have soared in the past few days thanks to positive data about treatments unveiled at this week’s San Antonio Breast Cancer Symposium, an event that was held virtually.

Greenwich LifeSciences soared nearly 1,000% (no, that’s not a misprint) Wednesday and rose another 26.5% Thursday after presenting promising trial results for one of its breast cancer drugs.

Australian biotech Immutep (IMMP) more than doubled Wednesday and was up 15% Thursday after it showcased encouraging data for its own breast cancer treatment.

And another small biotech that is scheduled to reveal new data, Sellas Life Sciences (SLS), skyrocketed nearly 75% Wednesday and more than 175% Thursday.

The demand for these stocks is a clear sign that traders recognize cancer, and breast cancer in particular, is still a prevalent disease that plagues millions.

Any company that can develop an effective treatment – or better yet, a cure – for breast cancer could generate substantial revenue and earnings.

Still, investing in biotechs is one of the riskiest parts of the stock market. Many smaller companies generate little to no sales and are not yet profitable, as they need to plow big amounts of money into research and development.

To that end, all three companies have racked up losses in the past few years. That makes these stocks incredibly volatile and subject to the whims of momentum traders, who are looking to buy and sell based on little more than information about clinical tests in press releases.

And we all know the adage about how what goes up must come down. Shares of Greenwich LifeSciences plunged 25% Friday while Immutep and Stellas each crashed by more than 35%.