Understanding Buprenorphine for Opioid Use Disorder
Buprenorphine is a cornerstone of medication-assisted treatment (MAT) for opioid use disorder (OUD). It is a partial opioid agonist, binding to the brain's opioid receptors and activating them less powerfully than full agonists. This helps reduce cravings and withdrawal symptoms without producing intense euphoria and has a "ceiling effect" that lowers overdose risk. Buprenorphine also blocks the effects of other opioids, supporting recovery.
Daily oral buprenorphine forms exist, but challenges with adherence and misuse led to the development of extended-release formulations like Probuphine and Sublocade, designed for sustained release over longer periods.
What Was Probuphine?
Approved by the FDA in 2016, Probuphine was the first long-acting buprenorphine product for opioid dependence maintenance. It was intended for patients stable on low-to-moderate doses of oral buprenorphine.
Administration and Availability
Probuphine involved the surgical insertion of four rods under the skin of the upper arm by a certified provider. These implants released buprenorphine for up to six months and required surgical removal. A restricted program (Probuphine REMS) addressed risks related to insertion/removal, such as nerve damage. Probuphine has been discontinued in the United States.
What Is Sublocade?
Sublocade is a monthly extended-release buprenorphine injection approved by the FDA in 2017 for moderate-to-severe OUD. It is for adults stabilized on transmucosal buprenorphine for at least seven days.
Administration and Dosing
Sublocade is a subcutaneous injection, usually in the abdomen, given monthly by a healthcare provider. It uses a system that forms a solid mass under the skin, releasing buprenorphine over a month. Dosing typically starts at 300 mg for two months, followed by 100 mg monthly. Sublocade has a boxed warning against intravenous use due to embolism risk.
How Probuphine and Sublocade Differ
| Feature | Probuphine (Discontinued) | Sublocade (Available) |
|---|---|---|
| Administration | Four small, subdermal implants inserted surgically into the upper arm. | One monthly subcutaneous injection administered by a healthcare provider, typically in the abdomen. |
| Duration | Lasts for up to 6 months. | Administered monthly. |
| Mechanism | Releases buprenorphine from a solid, ethylene-vinyl acetate rod. | Uses the Atrigel delivery system, forming a solid depot under the skin that biodegrades over time. |
| Requirement | For patients clinically stable on low-to-moderate oral buprenorphine (≤ 8mg per day). | For patients stabilized on transmucosal buprenorphine for at least seven days. |
| Reversibility | Requires a surgical procedure for removal. | No removal necessary; the depot dissolves and biodegrades over time. |
| Availability | No longer available for prescription in the U.S. | Currently available and widely used for OUD treatment. |
The Evolution of Treatment and Patient Choice
With Probuphine's discontinuation, Sublocade is a primary extended-release injectable buprenorphine option in the U.S.. Both aimed to improve adherence by removing the need for daily medication, reducing relapse risk.
For long-acting buprenorphine, discussions with a provider would focus on Sublocade and its requirements. Other options like injectable Brixadi also exist, offering more choices. Buprenorphine treatment should be part of a comprehensive plan including counseling.
Conclusion: Choosing the Right Path Forward
The main differences between Probuphine and Sublocade are administration and availability. Probuphine, a six-month implant, is discontinued, while Sublocade, a monthly injection, is available. Both improved adherence over daily oral buprenorphine. Probuphine's discontinuation highlights the changing landscape of pharmacology, but Sublocade and other options ensure access to effective long-acting buprenorphine for recovery. SAMHSA offers valuable information on OUD medications.
