In many ways, the biotech industry could be described as Wall Street's roulette wheel. The odds are certainly against your succeeding, with many drug developers losing money and looking to simply get their first drug approved. However, for those that do succeed, the returns can be enormous for investors.

But how much do you really know about the inner workings of the biotech industry? Chances are, far less than you realize. Here are nine biotech stats that I'm pretty sure will blow the average reader, and investor, away.

A biotech lab researcher using a pipette with test tubes.

Image source: Getty Images.

1. 68,000 disease states

According to the World Health Organization's ICD-10 (International Classification of Diseases), released in 2015, insurance companies classify approximately 68,000 disease states. Mind you, the difference between disease states could be minute in certain instances, but it nonetheless describes just how many new diseases have been discovered with the help of diagnostic and genetic testing equipment over the past couple of decades. This large number of diseases represents a seemingly endless opportunity for biotech companies.

2. 12 years

On average, it takes an experimental drug that's discovered in a laboratory setting 12 years to reach the patient (if it makes it at all), according to the California Biomedical Research Association. The process takes so incredibly long because of the testing involved. Beyond the discovery phase are the ex-vivo and in-vivo laboratory phases, preclinical testing in animal models, approval from the Food and Drug Administration to run clinical trials, and then human clinical testing in phases 1, 2, and 3. Finally, the FDA needs to approve a drug before it can be marketed to consumers. That means today's newest drugs were possibly conceptualized in a lab over a decade ago.

3. $2.56 billion

Based on figures from a recent analysis by the Tufts Center for the Study of Drug Development, the average cost to develop a drug and gain marketing approval is $2.56 billion.  Mind you, that figure includes an estimated $1.4 billion in out-of-pocket costs and $1.16 billion in time costs -- essentially, the returns that investors forgo while waiting for a drug to be developed and approved by the FDA. And we wonder why drug prices are so high.

A rising stack of pills on a pile of money.

Image source: Getty Images.

4. $58.8 billion

According to PhRMA's 2016 Biopharmaceutical Research Industry Profile report, association members spent an estimated $58.8 billion was spent on research and development (R&D) in 2015. That figure is up from $26 billion in 2000, $8.4 billion in 1990, and just $2 billion in aggregate in 1980.  Biotech blue chip Celgene (NASDAQ:CELG) is among the top spenders on R&D, between its own product development and its dozens of collaborations. In the first quarter, it dropped just shy of $1 billion in R&D, putting it on track for $4 billion in R&D expense in 2017 alone. However, given its expansive pipeline and double-digit growth rate, it's money well spent.

5. 1 in 5,000

Another reason prescription drug costs are so high is that the odds are significantly stacked against an experimental drug's chances of making it to pharmacy shelves. Just five out of every 5,000 drugs that enters preclinical testing will wind up making its way to human clinical trials -- that's a whopping 0.1% -- and only one out of every five experimental drugs that moves from preclinical to clinical studies finds its way to the patient. In other words, just one out of every 5,000 drugs in preclinical testing will ever see the light of day in a pharmacy.

6. 41 orphan drug approvals per year (2013-2015)

Over the past couple of decades, pharmaceutical and biotech companies have been placing extra focus on orphan diseases -- those that affect fewer than 200,000 patients in the U.S. Between 2013 and 2015, the FDA approved an average of 41 orphan disease drugs each year. By comparison, an average of just 13 were approved per year between 2002 and 2004. This is how Alexon Pharmaceuticals (NASDAQ:ALXN) has been able to get away with charging around a half-million dollars a year for Soliris, a monoclonal antibody that treats two ultra-rare diseases. Soliris is once again the priciest drug in the world, with Glybera being removed from pharmacy shelves in April. 

A biotech researcher examining a blood sample and taking notes.

Image source: Getty Images.

7. 246,500

A quick check of ClinicalTrials.gov's home website shows that there are roughly 246,500 ongoing clinical studies across 50 states and in 200 countries. Overall, 38% of these studies are being conducted in the U.S. only, with 56% being conducted outside the U.S., and 5% ongoing in both the U.S. and overseas simultaneously. 

8. 91%

Something else worth noting in PhRMA's aforementioned report is that generic usage is on the rise. Since patents protect branded drugs for only 20 years from the data of their investigational new drug approval from the FDA, generic-drug makers have an endless supply of opportunity to grab market share. PhRMA's report suggests that generic prescriptions accounted for 91% of all scripts doctors wrote in 2015, up from just 49% in 2000. 

9. 4.4 million

Finally, the biopharmaceutical industry is also a major job creator. In 2015, some 854,000 jobs in the U.S. were directly related to biopharmaceutical drug development. However, if we factor in jobs that are indirectly affected by the biotech industry, the figure jumps to approximately 4.4 million. 

Sean Williams has no position in any stocks mentioned. The Motley Fool owns shares of and recommends Celgene. The Motley Fool has a disclosure policy.