Christmas may be less than a month away, but Santa isn't going to cut the biotechnology and pharmaceutical sectors any breaks. Instead, six decisions are expected on new or supplemental new drug applications and three FDA advisory panel meetings are on the docket in December. That doesn't negate the possibility of cookies and milk being served, but it doesn't exactly give the FDA or the pharmaceutical sector a cakewalk into the new year.

As an investor, it means you'll need to stay on your toes -- especially with three incredibly important FDA actions expected in December. Regardless of whether you're a health care investing novice or consider yourself a seasoned pro, these three FDA actions should be circled on your calendars in the coming weeks. 

Dec. 8: Sofosbuvir PDUFA
I'm having trouble differentiating the importance of these three FDA actions, as they all demand a ton of attention, but Gilead Sciences' (GILD -1.15%) oral hepatitis C drug sofosbuvir could steal the show.

Sofosbuvir is widely expected to be approved after the FDA's advisory panel last month gave it a unanimous thumbs-up (15-0) for treating genotypes 2 and 3 of the disease in combination with ribavirin and without the need for IV interferon, as well as for treating genotypes 1 and 4 in combination with interferon and ribavirin (also a 15-0 vote). In late-stage trials, sofosbuvir was effective at delivering a sustained virologic response (i.e., a level where the disease is undetectable) after just 12 weeks in 90% of genotype 1 patients (the most common form of hepatitis C), while demonstrating a robust improvement in treating type 2 and 3 hepatitis C with an SVR of 78%. 

It certainly looks like sofosbuvir won't be alone, with the breakthrough therapy designated direct-acting antiviral combo drug from AbbVie also working its way through late-stage tests with equally impressive results. But sofosbuvir should make it to market well before AbbVie's DAA combo which could be all the head start that Gilead needs. With peak sales estimates, according to FierceBiotech, now hovering around $7 billion, this is a drug decision you simply can't afford to miss!

Dec. 12: Forxiga FDA panel review
If at first you don't succeed, try, try again! AstraZeneca (AZN -0.25%) and Bristol-Myers Squibb (BMY 0.96%) are attempting again to get their revolutionary SGLT2-inhibiting type 2 diabetes drug, Forxiga, approved in the U.S. -- but first it'll face a date with the firing squad known as the FDA's advisory panel on Dec. 12.

A quick refresher: Efficacy was never the issue with Forxiga, as AstraZeneca and Bristol-Myers Squibb actually managed to get their drug approved in the European Union late last year. However, Forxiga was turned away in the U.S. because of potentially elevated risks of liver damage, as well as bladder and breast cancer, associated with the drug.

After nearly two years, the companies come back to the table with some 26 mid and late-stage safety trial results spanning roughly 12,000 diabetes patients, which they believe will help demonstrate once and for all that the benefit profile of Forxiga far outweighs any prospective risks. Also working in Forxiga's favor is that Johnson & Johnson's Invokana, another SGLT2 inhibitor, was approved earlier this year; that may help loosen the FDA panel's safety concerns a bit.

The allure of SGLT2 inhibitors is that they work in the kidneys as opposed to the pancreas and liver, allowing patients to get rid of excess glucose that is blocked from absorption through their urine. Furthermore, while DPP-4 inhibitors -- the most commonly prescribed type 2 diabetes mellitus medication -- are weight-neutral, SGLT2 inhibitors have been shown as a side effect to cause weight loss! Obesity is a common ailment that often goes hand in hand with type 2 diabetes, so Forxiga could offer blockbuster sales potential as a next-generate type 2 diabetes drug.

Dec. 18: Anoro Ellipta PDUFA
Last but certainly not least, investors in GlaxoSmithKline (GSK -0.83%) and Theravance (NASDAQ: THRX) will have a chance to breathe a sigh of relief as their second inhaled chronic obstructive pulmonary disorder, or COPD, therapy is due up for a decision by the FDA on Dec. 18.

If you recall, GlaxoSmithKline and Theravance won approval for their long-acting inhaled therapy Breo Ellipta in May for the maintenance treatment of COPD and in reducing exacerbations of COPD in patients. Now the duo is hoping to get its LABA/LAMA combo, Anoro Ellipta, which is targeted at improving lung function for people with COPD and who are predominantly smokers, approved and on pharmacy shelves within a matter of weeks.

As of now, things look favorable for an approval after the FDA advisory panel in September voted 11-2 in favor of recommending Anoro Ellipta for approval. The panel did suggest the company conduct a number of longer-term safety studies, especially on patients' cardiovascular health, but didn't seem held up on this one concern. Although the FDA isn't required to follow the suggestions of its advisory panel, that body's recommendation more often that not tells the tale of what to expect come decision day.

If approved, Anoro Ellipta offers peak sales potential of $2 billion by 2018 and would practically solidify Glaxo and Theravance as major players in the COPD market throughout the remainder of the decade.