Medical Marijuana: A Challenge to Traditional Pain Relief?

Harriet Kozak

Medical use of marijuana for a broad range of conditions is expanding rapidly in the US, as legalization gathers pace and investors flock to a booming market. A January 2017 report for the National Academies of Sciences, Engineering and Medicine (NASEM) found substantial or conclusive evidence of marijuana’s therapeutic benefit in chronic pain, multiple sclerosis and chemotherapy-induced nausea and vomiting. Other, more tentative US state-approved indications include diabetes, glaucoma, epilepsy, migraine, post-traumatic stress disorder, hepatitis C, Crohn’s disease, Parkinson’s disease and Tourette syndrome.

Medical use has strong support from patients and the public. One recent poll showed that 93% of US voters supported legalizing marijuana for medical purposes while 71% opposed government enforcement of federal laws against marijuana in liberal states. Moreover, in 2014 a WebMD/Medscape survey of 1,544 doctors in 48 US states found that 56% supported the legalization of medical marijuana nationwide.

All the same, variable estimates suggest an uncertain future for this market. New Frontier Data, an independent analytics company specializing in the marijuana industry, forecasts that medical sales will reach $5.3 billion this year, accounting for 67% of the overall US marijuana market, and $13.2 billion by 2025 in states where medical use is already legal. Hexa Research believes the US medical-marijuana market will be worth nearly $20 billion by 2024.

Federal versus state  

One stumbling block to market growth is the tension between federal conservatism and state liberalism over medical uses of marijuana. In recent years, state-level concessions on medical marijuana were protected by the Rohrabacher–Farr amendment, which Congress finally passed in 2014. To date, 29 US states plus the District of Columbia have legalized medical marijuana, subject to a variety of conditions and approved indications. 

The Rohrabacher–Farr amendment prohibits the Department of Justice from using federal funds to prosecute violations of federal law related to medical marijuana. However, it needs to be reviewed annually. While the Senate recently agreed to re-attach the amendment to this year’s federal spending bill, the House Rules Committee blocked it at the urging of Attorney General Jeff Sessions, who blames medical marijuana for aggravating opioid abuse and violent crime in the US[1][2].

At federal level, the Drug Enforcement Administration still classes marijuana as a Schedule I controlled substance, on a par with heroin, ecstasy and LSD. That means the drug has high potential for abuse and no currently accepted medical use. The Schedule I designation also creates a number of barriers to research.

Scientific evidence is another grey area for medical marijuana, not least due to the difficulties of conducting clinical research under restrictive scheduling conditions.  The NASEM report also raised concerns about marijuana risks in areas such as road safety, respiratory conditions and mental health. The potential social impact of liberalizing marijuana use is evident from the legislative path taken recently by Canada, which included a ‘zero-tolerance’ approach to people driving under the influence of marijuana or other drugs.

Taking the pain from pharma

Running clinical trials to substantiate medical benefits would be easier in the US if marijuana sat in Schedule II, along with prescription drugs such as hydrocodone and oxycodone. Despite their more permissive scheduling, these painkillers are associated with an epidemic of opioid abuse, dependence and overdose. The number of drug overdose deaths involving prescription opioids has more than quadrupled in the US since 1999.

The public has been voting with its feet. Chronic pain is one category in which medical marijuana already presents a viable alternative to mainstream medicine. In an analysis by Marijuana Business Daily in 2016, 64.2% of registered patients in eight US states listed chronic/severe pain as a reason for using medical marijuana. A study this year in Drug and Alcohol Dependence reported that hospitalization rates from painkiller abuse and addiction dropped by 23% on average in states offering medical marijuana, while hospital cases of opioid overdose fell by 13%.

In our recent Living with Pain study conducted amongst 390 adults with chronic pain in the US, we found a high level of unmet need around long-term relief, as well as significant concerns about opioid addiction. A quarter of those who were taking opioids said they worried about becoming addicted and were very likely stop taking opioids for that reason. A further 23% were also worried about addiction but felt they were unlikely to cease treatment as a result. Nearly half of patients with chronic pain are looking for better pain relief and 44% for longer-lasting pain relief. A third of patients were worried about the potential for addiction.

The US public’s enthusiasm for medical marijuana as a pain remedy indicates just how much willingness there is to embrace alternative medicine when questions are raised over the integrity of mainstream pharmaceuticals. New Frontier Data suggests that if medical marijuana were legalized nationwide in the US, pharmaceutical expenditure on nine of the conditions designated by the National Academies of Science as most amenable to marijuana therapy could fall by $18.5 billion between 2016 and 2019.

If the momentum for legalization does continue in the US, it seems inevitable that medical marijuana will become more regulated, standardized and corporatized, as investment pours in, small businesses move out and prices moderate. That may be something the pharmaceutical industry needs to keep an eye on.

Something else to take note of is the grass-roots, homegrown, patient-driven nature of medical marijuana. At a time when drug costs and pharmaceutical-industry practices remain an easy target for criticism, companies need to work harder at delivering ‘whole-health’ solutions and substantiating the promise of patient-centric medicine.

In the chronic pain category, the patient voice is making itself heard by switching to a drug whose legal status remains uncertain and whose medical benefits could still be questionable. Even taking into account the special circumstances of opioid abuse, the pharmaceutical industry cannot afford to ignore the implications: sometimes patient power means opting for something completely different.   

Harriet Kozak is US President, Research Partnership.

[1] Trump and Sessions are ignoring voters' overwhelming support for medical marijuana. Will Congress listen? Editorial. Los Angeles Times. 9 September 2017.  Retrieved from http://www.latimes.com/opinion/editorials/la-ed-medical-marijuana-20170909-story.html.

[2]Attorney General Sessions’ Letter to Congress Sends Mixed Messages on Medical Cannabis. New Frontier Data. 14 June 2017. Retrieved from https://globenewswire.com/news-release/2017/06/14/1018614/0/en/Attorney-General-Sessions-Letter-to-Congress-Sends-Mixed-Messages-on-Medical-Cannabis.html.