Susineridine

Susineridine
Clinical data
Other names	YZJ-4729; YZJ4729
Routes of; administration	Intravenous
Drug class	μ-Opioid receptor biased partial agonist; Analgesic
Pharmacokinetic data
Elimination half-life	0.9–2.5 hours
Identifiers
	IUPAC name 6-propan-2-yl-N-[2-[(9R)-9-pyridin-2-yl-6-oxaspiro[4.5]decan-9-yl]ethyl]-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazol-4-amine;
CAS Number	2667632-87-1;
PubChem CID	156805910;
Chemical and physical data
Formula	C25H36N4O
Molar mass	408.590 g·mol−1
3D model (JSmol)	Interactive image;
	SMILES CC(C)C1CC(C2=CC=NN12)NCC[C@]3(CCOC4(C3)CCCC4)C5=CC=CC=N5;
	InChI InChI=1S/C25H36N4O/c1-19(2)22-17-20(21-8-14-28-29(21)22)26-15-11-24(23-7-3-6-13-27-23)12-16-30-25(18-24)9-4-5-10-25/h3,6-8,13-14,19-20,22,26H,4-5,9-12,15-18H2,1-2H3/t20?,22?,24-/m1/s1; Key:RUHISKJCCSWSHB-LLAFXHEGSA-N;

Susineridine (INNTooltip International Nonproprietary Name; developmental code name YZJ-4729) is an atypical μ-opioid receptor (MOR) agonist and opioid analgesic which is under development for the treatment of postoperative pain. It is given intravenously.

The drug acts as a selective biased partial agonist of the MOR, with functional selectivity for activation of G protein signaling over β-arrestin2 recruitment. Its mechanism of action and pharmacological activity are said to be similar to those of oliceridine. However, in-vitro findings suggest that susineridine may have a greater degree of G protein bias than oliceridine. The drug produces analgesic effects in multiple animal models of pain and produces less respiratory depression than morphine or oliceridine. The pharmacokinetics of susineridine in humans have been studied.

Susineridine was patented and first described in the scientific literature in 2023. It is under development by Shanghai Haiyan Pharmaceutical Technology in China. As of May 2025, the drug is in phase 3 clinical trials for postoperative pain.