Rational design of G_i-biased CB1 agonist with reduced side effects

Area of Science:

• Pharmacology
• Molecular Biology
• Medicinal Chemistry

Background:

• Cannabinoid receptor 1 (CB1) is a target for non-opioid analgesics.
• CB1-targeted drug development faces challenges due to adverse effects.

Purpose of the Study:

• To design novel G_i-biased CB1 agonists with reduced adverse effects.
• To utilize structure-activity relationship (SAR) and biased signaling for rational drug design.

Main Methods:

• Structure-activity relationship (SAR) analyses focused on biased signaling.
• Rational design of agonists (LZD503, LZD505) via structural spatial tuning.
• Cryo-electron microscopy (Cryo-EM) to determine CB1-G-protein complex structures.

Main Results:

• LZD503 and LZD505 were designed as G_i-biased CB1 agonists.
• Cryo-EM structures confirmed biased signaling conformational poses.
• Both compounds demonstrated pain alleviation and reduced adverse responses in mice.

Conclusions:

• Elucidated CB1 complex structures provide a framework for developing safer CB1-targeted analgesics.
• Structure-guided design of biased agonists offers a strategy to mitigate adverse effects.
• LZD503 and LZD505 represent promising candidates for next-generation non-opioid pain therapies.