What happened?

Shares of BrainStorm Cell Therapeutics (BCLI -1.69%) fell off a cliff Tuesday, and were down by 67% as of 12:20 p.m. EST after being down by as much as 68.2% earlier in the trading day. Traders are selling off shares of the clinical-stage biotech company following the release of negative top-line results from a phase 3 clinical trial for its leading candidate treatment. 

So what

BrainStorm Cell Therapeutics has been developing NurOwn as a potential treatment for amyotrophic lateral sclerosis (ALS), a nervous system disease that causes a progressive loss of muscle control and function. In the phase 3 study, NurOwn failed to achieve statistically significant efficacy results. With that said, it was generally well-tolerated from a safety standpoint, and did demonstrate some encouraging results; BrainStorm Cell Therapeutics says it has not given up on NurOwn yet.

Upward bound graph on a blackboard.

Image source: Getty Images.

"The findings from this clinical trial demonstrated that NurOwn treatment was associated with a clinically meaningful treatment response and consistent biomarker effects in known ALS disease pathways and that the ability of the clinical trial to demonstrate treatment effects compared to placebo are influenced by baseline disease status, as revealed through ALS function and key biomarkers," said BrainStorm Cell Therapeutics President Ralph Kern. "We are committed to advancing discussions with the FDA to identify regulatory pathways that may support NurOwn in ALS."

Now what 

While BrainStorm Cell Therapeutics' has other clinical trials underway, the one testing NurOwn as an ALS treatment was the one that had advanced the furthest. The company does have another phase 2 study in process, and as well as some pre-clinical studies. With its most promising program hitting a major roadblock, though, it isn't surprising that investors are offloading shares of the biotech company