FDA Suggests Endpoints for Opioid Treatments
Sponsors may not have to prove a proposed therapy helps addicts totally kick opioids to win FDA approval. But they will have to show it significantly cuts dependence on the potent pain meds, the agency says in new draft guidance.
The majority of clinical trials for proposed medicine-assisted treatments for opioid addiction focus on how well they curb use. But “sponsors and other stakeholders often mistakenly believe that using a change in drug use patterns as an endpoint always requires complete abstinence,” the FDA says, noting it’s not always possible to “have absolute confidence” someone has completely kicked the habit.
So the agency says it may be open to other endpoints for medicine-assisted therapy. Among those suggested in the draft guidance:
- Adverse outcomes such as deaths, emergency room trips and hepatitis C outbreaks. (The agency acknowledges that, to capture this kind of data, trials may need to study a large number of patients for a long period of time — and may make such studies impractical to support initial marketing approval.)
- Whether a medicine can help change a patient’s official diagnosis (as laid out by the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, the famed DSM-V)
- Patient-reported outcomes. Are patients (or their family) telling researchers that they’re sleeping better or that their mood has improved after taking a new medicine for opioid addiction? Sponsors could also use patient reports to come up with a concrete measure for cravings.
The FDA stresses that researchers should not focus on whether a med helps addicts stay in treatment. “Many features of trial design can produce incentives to remain in treatment without accruing clinical benefit,” the draft guidance states.
The FDA has only approved three medicines — methadone, buprenorphine (most commonly known by its brand name, Suboxone) and naltrexone (most commonly known by its brand name, Vivitrol) — to help treat addiction. Methadone and Suboxone are themselves derived from opioids and Vivitrol can be very expensive — up to $1,300 per monthly injection.
FDA records show there are currently 161 open clinical trials dealing with medication-assisted therapy in which drugs such as methadone are used in combination with a broader treatment plan. Most of the trials focus on the non-medicinal side of treatment. Only two — a British Columbia study testing the effects of opium tincture against methadone and a nationwide study by Kaiser Permanente on the best way to manage Suboxone treatments for addicts — are testing the impact of the drugs themselves.
Read the FDA’s draft guidance here: www.fdanews.com/08-06-18-OpioidGuidance.pdf.