High Hopes: Can Abuse-Deterrent Drugs Prevent Opioid Addiction?

In many ways, the guidelines present a new era in opioid development, one in which the drugs themselves may manage user behavior and actively participate in drug abuse prevention. They also signal extraordinary support for the young science of abuse-deterrent pharmaceutical design, and present an opportunity to nurture technological growth to more fully protect opioid users from developing addictions and overdosing. Already we have seen a surge in research and development of abuse-deterrent drugs, along with several new FDA approvals and lively public discourse regarding their potential and shortcomings. So what are the abuse-deterrent technologies being used today? There are currently four main components which may be used alone or in combination:

Physical/Chemical Barriers

One of the primary abuse-deterrent strategies used by pharmaceutical manufacturers is tamper proofing by altering the physical or chemical characteristics of the drug to prevent product manipulation, particularly for purposes of non-oral administration. One of the most highly publicized examples of this is Hysingla, an abuse-deterrent tablet form of hydrocodone that received FDA approval last year. By combining unique polymers and processing methods, the tablets are extremely difficult to break or crush, inhibiting the user’s ability to snort, chew, or inject it. If immersed in water, the pills become “a gelatinous, gooey mass that doesn’t pull into a syringe easily.”

Opioid Antagonists

Opioid antagonists can disrupt the effects of opioid painkillers, making them instrumental in the treatment of opioid overdoses, and also giving them unique protective properties when incorporated in abuse-deterrent medications. Drug formulations that include antagonists can be designed to keep the antagonist latent under normal use circumstances, and activate it only under certain conditions, such as breaking the pill or ingesting large doses of intact tablets. Targiniq, also made by Purdue, combines oxycodone with naloxone, which blocks opioid receptors and can decrease the efficacy of the oxycodone if crushed or dissolved.

Aversion

Aversion formulations produce unpleasant effects if misused, making them inhospitable to abuse. Acura Pharmaceuticals, for example, has created opioid tablets that will break into chunks when crushed and cause “burning and irritation to the nasal passages” if snorted. These drugs may also be designed to induce physical discomfort such as chills, itching, sweating, and flushing when orally ingested in excess.

Preserving Extended Release

Extended-release (ER) formulations were designed in part to prevent abuse by distributing the potency of the opioid over time; indeed, when taken orally as an intact tablet, users looking to get high overwhelmingly prefer instant release opiates. However, when standard ER formulas like OxyCodone are crushed or dissolved, the ER mechanism is destroyed and higher concentrations of the drug are made immediately available, making them an extremely appealing option for opioid addicts. To address this, pharmaceutical companies are now developing formulas that preserve a drug’s extended release mechanism even when physically altered.

While there is promising, if tentative, research supporting the efficacy of these abuse-deterrent efforts, some addicts and addiction experts are skeptical about their potential impact. Many of the designs are heavily targeted toward preventing non-oral consumption, as some users do manipulate the drugs to create a more intense rush. However, Dr. Andrew Kolodny, chief medical officer at Phoenix House, says, “I’ve been treating opioid addition for over ten years and I have very rarely come across people who develop that disease from snorting or injecting the pills. People develop that disease from using the pills orally.” As such, these abuse-deterrent strategies may not be designed to address actual user behavior and the way most people’s addictions evolve. With this in mind, deterrent designs that combine physical/chemical barriers with orally-targeted opioid antagonist or aversion formulations are considered by many to be the most promising strategies to prevent new addictions and overdoses. As abuse-deterrent technologies continue to mature, more sophisticated mechanisms may be come available to offer more fully realized protective benefits. A number of auspicious possibilities are already on the horizon, including prodrug formulations that limit system exposure by preventing the activation of opioid activity until metabolized in the digestive tract, and delivery mechanisms that eliminate self-administering of the drugs, including subcutaneous implants and depot injections.