spec sheet8 rows
ADL-5747 is an investigational, orally active, selective delta (delta) opioid receptor agonist that was developed as a non-classical analgesic. It progressed into clinical testing but development was discontinued after failing to advance past Phase II.
- Studied preclinically for pain relief via delta-opioid receptor activation
- Did not cause receptor internalization or hyperlocomotion in mouse models, unlike earlier delta agonists
- Did not demonstrate sufficient efficacy in Phase II human trials
Overview
A delta-opioid painkiller candidate that looked interesting because it avoided some of the receptor internalization seen with other delta agonists, but it didn't pan out clinically.
Mechanism
ADL-5747 selectively activates the delta-opioid receptor (DOR) rather than the mu-opioid receptor targeted by classical opioids like morphine. In animal studies its analgesic effect involved delta receptors expressed on peripheral Nav1.8-positive sensory neurons. Unlike some other delta agonists (e.g. SNC80), ADL-5747 did not induce receptor internalization or hyperlocomotion in mice, a profile that was hoped to reduce tolerance and side effects.
receptor fingerprint
Delta-opioid receptor (DOR)Agonist
Safetyrisks and cautions, not medical advice
ADL-5747 was tested in Phase I/II human trials for pain but did not demonstrate sufficient efficacy to continue development. Delta-opioid selective agonists as a class have raised concerns in animal models about convulsant activity at high doses, though ADL-5747 specifically was designed to minimize the locomotor and receptor-internalization effects seen with earlier delta agonists.
Subjective profileweighing the evidence above
A sound idea that got a fair test and did not clear it. Delta-opioid analgesia without the mu-receptor baggage is still worth pursuing, but this particular compound failed on efficacy in Phase II and has nothing further to offer.
Resources
This entry is here for reference.
Research
- 1.Spirocyclic Delta Opioid Receptor Agonists for the Treatment of Pain: Discovery of N,N-Diethyl-3-hydroxy-4-(spiro[chromene-2,4'-piperidine]-4-yl) Benzamide (ADL5747)
- 2.δ-Opioid mechanisms for ADL5747 and ADL5859 effects in mice: analgesia, locomotion, and receptor internalization.
2 listed here; entry last updated August 2026
Reviews
My notesprivate to this device
FAQ
What is ADL-5747 used for?
It was developed as an experimental pain reliever that selectively activates delta-opioid receptors, but it never became an approved medication.
How does ADL-5747 work?
It selectively binds and activates delta-opioid receptors, a different opioid receptor subtype than the mu receptors targeted by classical opioids like morphine.
Is ADL-5747 well-researched?
It has published medicinal chemistry and preclinical pharmacology data and reached Phase II human trials, but development was discontinued due to insufficient efficacy.
Adverse effects
- Did not demonstrate sufficient efficacy in Phase II human trials
Notes and cautions
- Delta-opioid agonists as a class have shown convulsant risk in some animal studies