What happened

Shares of Sangamo Therapeutics Inc. (SGMO -3.67%), a pre-commercial biotechnology company developing gene therapies, fell 25.3% in October, according to data from S&P Global Market Intelligence. After completing the acquisition of a French start-up to begin the month, the stock followed the rest of its industry lower.

So what 

The month of October was a rough one across the board. The Nasdaq Biotechnology Index fell 13.9%, and companies like Sangamo that don't have any approved drugs to sell fell harder than those with reliable revenue streams.

Frustrated trader yelling at his computer screen.

Image source: Getty Images.

Sangamo investors were less than thrilled with the $82 million acquisition of TxCell, a French biotech developing regulatory T cells. The acquired company won't be ready to submit its first clinical-trial authorization application until next year, but Sangamo insists the acquisition will accelerate its entry into the market for cellular cancer therapies.

Now what

At the moment, just two cellular cancer therapies are generating significant sales, and their first several quarters haven't been remarkable. A report last month in Nature Reviews Drug Discovery found 412 experimental cellular cancer therapies in clinical-stage development, which means there could be a lot more potential competition by the time Sangamo has one of its own in human testing.

While Sangamo's oncology pipeline probably isn't going anywhere fast, investors can look forward to results from the Alta study with SB-525, a hemophilia candidate partnered with Pfizer (PFE 0.66%). In October, a safety monitoring committee said it's safe enough to try a higher dosage, and Sangamo will present efficacy data from the study once dose escalation is complete.

So far in November, Sangamo has fallen another 20.1%