Fig. 2.

Design and production of fentanyl and fentanyl/heroin conjugate vaccines. Using synthetic chemistry, a specific linker is added to the fentanyl or fentanyl/heroin without affecting biological functionality to create a hapten. Linkage of the fentanyl or fentanyl/heroin hapten to the carrier protein occurs through bioconjugate chemistry, and subsequent adjuvating of the immunologic stimulant generates complete vaccines. These vaccines have been tested in mice, rats, and nonhuman primates, where they have been shown to enhance innate and adaptive immunity, produce fentanyl-specific antibodies, sequester opioid drugs in the periphery, and prevent them from entering the brain, thus attenuating the reinforcing effects of fentanyl or fentanyl-contaminated heroin. IV, intravenous; IM, intramuscular; SC, subcutaneous; IP, intraperitoneal.