Every year, the promise of safer and more effective drugs coming to market gives an aging population hope. According to the Phrma organization's website, roughly $49 billion was spent on researching some 2,900 compounds last year alone. The truly amazing part is that we've only touched the tip of the iceberg on what diseases are left to be researched and/or cured. We still have a long way to go with regards to cancer research, and many rare diseases still have largely unmet needs.

Each week for a total of five weeks, I'm looking at an upcoming drug that has every indication of being not only a revenue blockbuster, but a true life changer. Keep in mind that none of the five drug hopefuls I'm highlighting are approved by the Food and Drug Administration, so there are plenty of obstacles left to be encountered, including safety data, which could still stand in the way of an ultimate approval.

 In the previous four parts of this five part series I've highlighted four game-changing drugs:

For the final week of this series, I want to take a closer look at LAMA/LABA, a once-daily inhaled compound manufactured by Theravance (UNKNOWN:THRX.DL) and licensed to GlaxoSmithKline (NYSE:GSK) for the treatment of chronic obstructive pulmonary disease, or COPD.

According to the World Health Organization, as of 2004 there were an estimated 64 million people with COPD, and WHO expects this figure to rise by an additional 30% by 2014, largely because of tobacco smoke exposure.  COPD, which is often associated with smokers, is an (as of now) incurable and progressive disease marked by the narrowing of the airways of the lungs, leading to shortness of breath.

At the moment, there are just a handful of drugs on the market to treat COPD. Merck's (NYSE:MRK) Foradil inhaler, acquired when it purchased Schering-Plough, comes with a black-box warning, added in 2005 as a reminder that some patients had a severe exacerbation of their asthma symptoms while taking the drug. Other previously manufactured brand names like the Atrovent inhaler from Boehringer Ingelheim, and even Glaxo's Advair, have come off patent, and generic producers like Teva Pharmaceutical (NYSE:TEVA) are hoping to make their own versions of the drug.

In looking to replace Advair, Theravance and Glaxo have teamed up to create a new type of inhaled COPD medication aimed at improving breathing for patients and slowing the progression of the disease. The two molecules, umeclidium bromide -- a long-acting muscarinic antagonist, or LAMA -- and vilanterol -- a long-acting beta-2 antagonist, or LABA -- were combined into an all-powder inhaler, and the results appear very good so far.

If there's one quibble I have with Theravance and Glaxo, it's that the combo is being very vague about the specific results of its late-stage study with once-daily LAMA/LABA. In early July, the duo noted that in four different trials, measuring various dosing levels, as well as efficacy and safety, LAMA/LABA performed much better than the placebo. In two of those trials, as detailed by the Fool's Brian Orelli, LAMA/LABA was compared to Pfizer (NYSE:PFE) and Boehringer Ingelheim's Spiriva and proved its non-inferiority in both trials. Theravance and Glaxo have claimed that they plan to fully detail their late-stage findings at scientific meetings in the future.

With such a growing number of people worldwide being diagnosed with COPD, clearly there's an unmet need for improvement in this arena, and it appears that with the new drug application filing, which was submitted on Tuesday to U.S. regulators, that those suffering from COPD may soon have better choices available. The combo is also working on a completely separate drug for COPD known as Relovair -- and who knows, maybe I'll be featuring it next year?