Emideltide (Delta Sleep-Inducing Peptide) and the FDA 503A Decision

The Short Answer

At the July 24, 2026 PCAC meeting, FDA proposed that Emideltide (free base) and Emideltide acetate not be added to the 503A Bulks List. The nomination (later withdrawn, with FDA proceeding) sought emideltide by the subcutaneous route for insomnia — FDA focused on chronic insomnia — with opioid withdrawal also examined. FDA found the effectiveness and safety evidence insufficient for the proposed route.

What Emideltide Is

Emideltide is the INN for the delta sleep-inducing peptide (DSIP), a nine-amino-acid neuropeptide studied in humans since at least 1981. It has been examined for sleep and for withdrawal syndromes. See our delta sleep-inducing peptide page for background.

Characterization: "Not Well-Characterized"

FDA deemed both forms not well-characterized, citing inconsistent naming conventions (USAN, INN, IUPAC) and missing critical characterization data. It also noted that because the free base has limited water solubility, particle-size-distribution control of the powder may be needed — a formulation consideration absent from the record.

Historical Use: Some Compounding Evidence

Unlike several other peptides in this review, emideltide has a longer documented footprint: there is evidence of use in compounding since at least 2018, and emideltide-related injection and intranasal products are available through integrative-neurology clinics, concierge and wellness services, and online retailers. Still, FDA found it unclear whether those specific products are compounded.

Effectiveness: IV Data Only, Inconclusive — and Nothing for the Proposed SC Route

This is the crux. No study evaluated effectiveness by the nominated subcutaneous route for chronic insomnia; the only data FDA found were for intravenous administration. And even the IV evidence was judged inconclusive and, at best, preliminary — short-term IV emideltide appeared to affect disturbed sleep in some studies, but the results were not persuasive. For opioid withdrawal, likewise only IV data existed, with positive but cautiously interpreted results limited by small studies.

Safety: An Opioid-System Signal Worth Naming

Nonclinically, emideltide has cross-species sleep-inducing properties mediated through opioid-dependent mechanisms — it does not bind opioid receptors directly but can stimulate calcium-dependent endorphin release. FDA flagged that this opioid-system stimulation could carry addictive liability, and that it did not identify nonclinical studies characterizing that risk. There are no safety data for the proposed SC route. IV data in small numbers of insomnia subjects reported no significant adverse effects, but withdrawal-symptom studies reported transient headache, nausea, vertigo, and cases of progressive hypotension after a second IV injection.

What It Means for Physicians

Emideltide/DSIP was not FDA-approved and remains so. See the pillar overview and confirm access with your 503A compounding partner. FDA-approved insomnia therapies exist and were noted as a weighing factor.

Key Takeaways

• FDA is proposing that Emideltide (free base and acetate) not join the 503A Bulks List.
• No effectiveness data exist for the nominated subcutaneous route; only inconclusive IV data were found.
• FDA raised a specific addictive-liability concern tied to emideltide's opioid-dependent mechanism, uncharacterized in nonclinical studies.
• No SC safety data; FDA-approved insomnia therapies already exist.

Frequently Asked Questions

Is emideltide the same as DSIP?
Yes. Emideltide is the international nonproprietary name for the delta sleep-inducing peptide, a nine-amino-acid neuropeptide.

Is emideltide banned by the FDA?
No. FDA is proposing that it not be added to the 503A Bulks List — an advisory-committee proposal, not a final rule. It was never FDA-approved.

Why did FDA flag addiction risk?
Emideltide's sleep and analgesic effects appear to work through opioid-dependent endorphin release, and FDA found no nonclinical studies characterizing whether that mechanism carries addictive liability.

Was there any evidence it helps sleep?
Only intravenous data, which FDA judged inconclusive and preliminary — and nothing for the nominated subcutaneous route.

Track Live FDA Peptide Status

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