Rapid induction with monthly injectable buprenorphine extended-release

A method of increasing the rate of retention in opioid use disorder treatment by a patient experiencing precipitated opioid withdrawal (POW), the method comprising rapid induction (RI) of buprenorphine by:

• (a) administering to the patient a transmucosal composition comprising buprenorphine as free base or a pharmaceutically acceptable salt, wherein the amount of buprenorphine is equivalent to about 2 mg to about 4 mg of buprenorphine free base,
• (b) administering a first extended-release composition to the patient by subcutaneous injection at least about 1 hour and no more than about 24 hours after administration of the transmucosal composition,
• the first extended-release composition comprising buprenorphine as free base or a pharmaceutically acceptable salt, in an amount equivalent to about 100 mg to about 300 mg of buprenorphine free base,
• (c) administering a second extended-release composition to the patient by subcutaneous injection about from about from about 7 to about 11 days after injection of the first extended-release composition,
• the second extended-release composition comprising buprenorphine as free base or a pharmaceutically acceptable salt, in an amount equivalent to about 100 mg to about 300 mg of buprenorphine free base, and
• (d) administering one or more monthly extended-release compositions to the patient by subcutaneous injection every 28 to 31 days starting 28 to 31 days after injection of the second extended-release composition,
• the monthly extended-release composition comprising buprenorphine as free base or a pharmaceutically acceptable salt, in an amount equivalent to about 100 mg to about 300 mg of buprenorphine free base,
• wherein the patient experiencing POW are fentanyl-positive, and
• wherein the rate of retention is increased through administration of the second extended-release composition relative to standard of care (SoC) and standard induction (SI) methods of buprenorphine induction.