There are few wars that the United States can conceivably say it's not won, but the war on illicit drugs and general drug abuse continues to be one such instance where there's no clear victory in sight.

According to a National Drug Threat Survey (link opens a PDF) conducted by the Drug Enforcement Agency, the use of illicit substances in 2011 was actually down, but only marginally, to 8.7% of the population aged 12 years and older from 8.9% in 2010. The NDTA study notes that certain regions of the country deal with difficult challenges based on their location relative to Mexico, a country with weaker drug-trafficking enforcement. The study specifically notes that heroin infiltration from Mexico into the U.S. continues to be a serious problem in a number of regions.

America's fastest growing drug problem
What the report also notes is that the fastest-growing drug problem isn't even an illicit drug of all. With the exception of marijuana, which is still the most widely used illicit drug, controlled prescription drugs, or CPDs, represent by far the most rapidly growing drug problem we have in America.

Source: DEA, National Drug Threat Survey 2007-2011, 2013.

According to the National Survey on Drug Use and Health, pain relievers are the most commonly abused CPD, with its data indicating that 6.1 million people (about 2.7% of the U.S. population) aged 12 years or older admitted to nonmedical use of psychotherapeutic drugs. When polled over the prior month, CPD use was 2.4% of the population, compared with 0.4% for hallucinogens and 0.5% for cocaine. Marijuana use, as noted, was notably higher at 7% of the polled population.

The truth of the matter is that prescription drug abuse is a very real and very serious problem, at least in the eyes of law enforcement agencies around the country, of which 28% identified CPDs as the top drug threat in their region. Worse yet, NDTS's data indicates that access to controlled prescription drugs is only increasing, and may grow even further as Obamacare expands patients' ability to see their doctor for preventive care purposes. Based on the responses from law-enforcement agencies, the high availability of CPDs increased from 40.7% in 2007 to 75.4% in 2013.

Notable steps have been taken to help curb the illegal use of prescription drugs, including disallowing the three top Internet search engines from allowing Internet pharmacies from advertising on the sidebars of search pages unless they're Verified Internet Pharmacy Practice Sites, and through encouraging Americans to turn in unused or unwanted prescription medications at a number of nationwide locations.

Ultimately, this isn't proving to be enough, as the data would suggest. High levels of CPD abuse are forcing the Food and Drug Administration to take a tougher stance on drug approvals, especially for chronic pain medications that are opioid-based, and it's pushing select drug developers to innovate new drug formulations that are abuse-resistant.

Source: DEA.

An area of immense opportunity
Yet within this innovation lies a genuine opportunity for biopharmaceutical companies to make a meaningful difference on reducing drug abuse, and for investors to potentially get rich. Let's have a closer look at a few of the leading companies involved in drug-abuse-resistant technologies and see what they're doing to reduce already high CPD abuse levels.

One company completely geared toward curbing CPD abuse is Acura Pharmaceuticals, which currently has two abuse-resistant products currently approved by the FDA. The first is Oxecta, a drug that treats moderate to severe pain and is licensed out to Pfizer (NYSE:PFE), while the second is Nexafed, a unique bioequivalent of the nasal decongestant Sudafed that will form a gummy gel if broken down and mixed with solvents typically used to create methamphetamine. Currently, Acura is working with federal regulators and discussing the possibility of bringing a new version of the painkiller hydrocodone to market. This hydrocodone-and-acetaminophen combo is currently in midstage studies. 

Another key group of players in this space is the combination of Pfizer, Pain Therapeutics (NASDAQ: PTIE), and DURECT (NASDAQ:DRRX), which are on their third try of developing Remoxy, an abuse-resistant, extended-release oxycodone capsule. The drug itself is designed to taste bad and is resistant to being ground down, injected, or snorted, which should reduce the chances for abuse. Unfortunately, even abuse-resistant pain meds are viewed with a discerning eye by the FDA, which has, on two previous occasions since 2009, issued a complete response rejection letter to all three parties. The trio announced this past October that a new set of studies would be giving Remoxy another attempt at an FDA approval.

I would increasingly look for drug-abuse-focused companies to step to the forefront in an effort to counteract a rising tide of CPD abuse and would certainly suggest you keep your eyes on these companies moving forward.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.