You can count the number of pure-play marijuana stocks with a market cap of around $3 billion on one hand -- and have several fingers left over. GW Pharmaceuticals (NASDAQ:GWPH) ranks as one of the largest marijuana stocks on the market. But when the biotech reported its third-quarter results in August, investors were disappointed that the company was delaying its U.S. regulatory submission of cannabidiol (CBD) product Epidiolex. Over 10% of GW Pharma's market cap was wiped out in the days following the announcement.

Those concerns were a thing of the past when the company announced its fourth-quarter results on Monday. This time around, GW Pharmaceuticals' management team had nothing but good news to discuss. Here are five important things to know from their comments about the leading cannabinoid-focused biotech's future. (Quotes from S&P Global Market Intelligence.) 

Marijuana buds on table next to beakers with green fluid

Image source: Getty Images.

1. Timeline for Epidiolex

GW Pharmaceuticals completed its U.S. regulatory submission of Epidiolex in October. CEO Justin Gover said the company expects to hear from the FDA by the end of December on whether or not the filing will be accepted. Assuming it is, Gover stated that GW anticipates that it will receive confirmation of an expedited review, which should lead to an FDA approval decision on Epidiolex in mid-2018. Chief Medical Officer Volker Knappertz said he thinks there's "a 50-50 chance of an AdCom," referring to the FDA's process of sometimes convening an advisory committee to review filings before a final decision is made.

If the FDA approves Epidiolex, the next step will be for the U.S. Drug Enforcement Administration (DEA) to classify the drug into the appropriate schedule. Knappertz cited data from a human abuse liability study of CBD being presented at the American Epilepsy Society meeting this week. He said this data gave GW Pharma "confidence in reaffirming our expectation that Epidiolex will likely be placed into at least Schedule IV by the DEA" if it gains FDA approval. The DEA defines Schedule IV drugs as those "with a low potential for abuse and low risk of dependence." 

Gover also said the company expects to submit its filing of Epidiolex for European approval by the end of 2017. He mentioned that GW Pharma's team has already met with European regulators. Gover expects the process to take a little over a year, with a decision on European approval for Epidiolex likely for the first quarter of 2019. 

2. Encouraging data related to interaction with clobazam

One worry that some investors have had is the interaction between Epidiolex and clobazam, a currently approved anti-epilepsy drug Lundbeck markets under the brand name Onfi. GW Pharma's executives have mentioned in the past that they weren't concerned about any interactions preventing regulatory approval. In his comments during the company's fourth-quarter call, Knappertz highlighted why they were confident. He said three poster presentations at the American Epilepsy Society meeting "all suggest that patients on Epidiolex are able to achieve clinically meaningful responses both on and off clobazam." He stated that the studies found no interaction between a 10 mg dose of Epidiolex and clobozam.

With a 20 mg dose of Epidiolex, Knappertz acknowledged there there "seems to be a minor interaction, meaning that, on clobazam, there's a slightly higher reduction in seizure frequency." However, he stressed that any difference was only minor.

3. Commercialization plans

Of course, winning approval is only one step along the path. What about commercialization plans for Epidiolex? Julian Gangolli, GW Pharmaceuticals' president of North America, stated that the company expects to deploy "a dedicated sales force of approximately 70 sales professionals to target the approximate 4,000 to 5,000 physicians that treat the majority of patients within the expected indications for Epidiolex, if approved." These sales reps will operate under the banner of GW's U.S. operating company name, Greenwich Biosciences.

Gangolli said the company is establishing relationships with key opinion leaders in epilepsy, including with the major epilepsy centers of excellence in the U.S. He also stated that GW is meeting one-on-one with private and government payers. Gover added that in the conversations, payers "have indicated that they absolutely understand the need for this product" and that he doesn't think payers will "impose any onerous prior authorization requirements" on Epidiolex. 

4. About potential competition

An analyst asked Gover about physician feedback related to use of Epidiolex in addition to Zogenix's (NASDAQ:ZGNX) ZX008. In late September, Zogenix announced positive results from a late-stage study of ZX008 in treating Dravet syndrome, one of the indications Epidiolex also targets. Here's how Gover responded:

There is no either/or concept within the concept of this treatment-resistant patients. If additional therapy can be added, then that is something physicians are keen to do. So I think the general feeling in the meeting, it's great to have the option with new differentiated antiepileptic drugs, and there hasn't with -- the epilepsy community's not been in that position for quite some time. So I think it's been a very good meeting with respect to the receptivity of the product and the new entrants into the marketplace. In these kind of patient populations that we're dealing with, we're 90% treatment-resistant in terms of sort of proportion, so a new therapy is something to be welcomed.

Is this just spin? I don't think so. Use of multiple drugs is a reality in the treatment of epilepsy patients. Even analysts bullish on GW project that Epidiolex will gain only a 33% market share. 

5. Upcoming pipeline milestones

All the buzz right now is rightly focused on Epidiolex in treating Dravet syndrome and Lennox-Gastaut syndrome (LGS). However, GW Pharmaceuticals has several other promising pipeline programs. 

Knappertz noted that results from a late-stage study of Epidiolex in treating tuberous sclerosis complex are expected in the second half of 2018. He also said results from the first part of a two-part phase 2/3 study in infantile spasms will come out in the first quarter of next year.

Beyond Epidiolex, Knappertz highlighted cannabidivarin. He said top-line results from a phase 2 study in adults with inadequately controlled focal seizures should be available in the first quarter of 2018. Knappertz also said GW hopes to regain full U.S. rights to Sativex, its cannabinoid oral spray approved in 30 countries outside the United States.

Looking ahead

In all, GW Pharmaceuticals' management team painted an attractive picture of the future for the biotech. I wouldn't be surprised if there are a few bumps along the way, but I think their view isn't too far off. Epidiolex appears to have a good shot at winning U.S. and European approval. I suspect payers won't present reimbursement hurdles that are too difficult to overcome. And I think GW's cannabinoid pipeline is quite promising. In my opinion, GW Pharmaceuticals continues to be one of the best marijuana stocks for investors to keep on their watch list. 

Keith Speights has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.