Combination of Cannabidiol and Low-Dose Buprenorphine Suggests Synergistic Analgesia and Attenuates Buprenorphine-Induced Respiratory Depression.

Abstract

Introduction: As opioid-related drug overdoses remain a public health crisis, there is a critical need for innovative approaches to developing safer analgesics with improved safety profiles. BDH-001 is a fixed-dose combination of low-dose buprenorphine (BUP) and cannabidiol (CBD) being developed as a safer analgesic than currently available opioids. The purpose of this study was to examine the analgesic and opioid-sparing effects of BDH-001 and to complete an in vivo safety assessment in rats. Methods: Analgesic effect of BDH-001 was assessed using the chronic constriction injury model of chronic neuropathic pain with pain threshold assessed via Von Frey testing. Drug-drug interaction effects on pharmacokinetic (PK) parameters were assessed in a single dose PK study in rodents. The effects on respiratory depression were also assessed and confirmed in two separate rodent studies performing blood gas analysis and measuring O₂ saturation. Results: BDH-001 (combination of subanalgesic BUP dose and CBD) resulted in statistically significant increases in pain threshold compared to saline (p < 0.001), CBD alone (p < 0.01), and BUP alone (p < 0.05). The half-life of BUP was significantly shorter in the presence of CBD compared to BUP alone (p = 0.008), with no significant changes in any other BUP pharmacokinetic parameter assessed. CBD was found to attenuate BUP-induced respiratory depression in rats when assessing blood gases (p < 0.05) and O₂ saturation (p < 0.05) over several time bins. Conclusions: Data obtained in the present study indicate the addition of CBD to BUP was opioid-sparing and attenuated BUP- but not morphine-induced respiratory depression. There was no evidence these findings were the result of a PK interaction. Results support the hypothesis that BDH-001, a fixed-dose combination of BUP and CBD, may provide effective analgesia with a more favorable safety profile.