What: After reporting fourth-quarter financial results and updating investors on the progress it's making in developing marijuana-based medicine, shares in GW Pharmaceuticals plc (NASDAQ:GWPH) toppled 14.9% last month, according to S&P Global Market Intelligence.

So what: Perhaps, no other biotechnology company is as committed to creating medicine from marijuana cannabinoids as GW Pharmaceuticals. The company has been researching THC- and CBD-derived medicine since the 1990s and it already markets a THC-based drug, Sativex, in Europe.

However, GW Pharmaceuticals has been stumbling lately, and that's taken a toll on its share price.

Last year, three pivotal late-stage studies evaluating its marijuana medicine for cancer pain failed to outperform a sugar pill, and another trial studying a marijuana medicine in schizophrenia patients also fell short of expectations.

Those failures were followed up by an admission by management in January that the company has material weaknesses in its accounting practices for clinical trial activities. And on Feb. 10, it updated investors on its financials, revealing that sales of Sativex were a tepid $5 million and that expenses eclipsed $40 million last quarter.

Now what: GW Pharmaceuticals management could use a win and it hopes to get it in the form of soon-to-wrap up studies in epilepsy.

Specifically, the company is conducting late-stage studies of Epidiolex, a drug derived from CBD, in patients with Dravet syndrome and Lennox-Gastaut syndrome. Those are rare conditions with a significant need for new treatment options, and a positive outcome for its trials could lead to a Food and Drug Administration approval that significantly boosts prospects.

Data from its epilepsy trials should be in the hands of management soon and investors, doctors, and patients should be able to dig into them this year. However, investors might want to take a wait-and-see approach to the company's shares. So far, GW Pharmaceuticals' plans to profit from marijuana medicine haven't materialized, and because of that, other investment ideas may make more sense right now. 

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