DSIP / Emideltide: how it got to PCAC

Background

Delta-sleep-inducing peptide (DSIP) is a nine-residue peptide of the sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu, recorded in PubChem under CID 68815 (PubChem CID 68815). The peptide was originally isolated by Schoenenberger and Monnier in the 1970s from cerebral venous blood of rabbits subjected to electrical stimulation of the medial thalamus, an experimental model in which sleep states were induced — hence the name. The foundational review by Graf and Kastin in Neuroscience & Biobehavioral Reviews in 1984 surveyed the early chemistry and distribution literature (PMID:9926346):

DSIP is a nonapeptide which has been isolated from the cerebral venous blood of rabbits in which sleep had been induced by electrical stimulation of the medial thalamus.

The name “Emideltide” appears in some nomination and trade-name materials in the international peptide market and refers to the same nine-residue sequence; the two names are used interchangeably for the molecule under PCAC review.

What’s on the agenda

DSIP / Emideltide is one of three peptides on the agenda of the FDA Pharmacy Compounding Advisory Committee meeting scheduled for July 24, 2026. The committee provides advisory recommendations to the FDA on whether a nominated bulk drug substance should be added to the 503A bulks list, the regulatory mechanism that permits licensed pharmacists to compound a substance for an identified patient pursuant to a valid prescription (FDA PCAC).

The path from initial nomination to a PCAC hearing typically involves the following steps, summarized by the FDA on its bulks-substance reference page (FDA bulks page):

1. A sponsor (a compounding pharmacy, an outsourcing facility, or a clinical advocate) submits a written nomination to the agency, accompanied by supporting clinical and scientific data.
2. FDA staff perform an initial review of the nomination and place the substance into one of four evaluation categories.
3. Substances reviewed in the highest-evidence category are added to the bulks list; lower-evidence categories may receive a PCAC referral, where committee members vote on a recommendation following a public meeting.
4. The FDA issues a final listing decision in the Federal Register; the decision is non-binding-on-PCAC and may differ from the committee’s vote.

DSIP appears on the July 24 agenda as a substance referred to PCAC, indicating that the agency’s preliminary review did not identify sufficient evidence to list the peptide without the committee’s input.

Why it matters

The peer-reviewed DSIP literature published since the original Schoenenberger isolation has been heterogeneous in quality and primarily preclinical. Mechanism-focused papers from the post-2000 era — for example, Khvatova and colleagues in Bulletin of Experimental Biology and Medicine in 2012, who reported mitochondrial-protective signals in rat brain tissue (PMID:23062365) — have explored hypothesized mechanisms but have not been accompanied by large, randomized, placebo-controlled trials in humans. There is no FDA-approved DSIP product, no European Medicines Agency authorization, and no Health Canada or TGA registration as of the date of this writing.

The July 24 PCAC discussion will, per the FDA’s own framework, weigh four factors: physicochemical characterization, safety signals from compounding use, evidence of effectiveness or lack of effectiveness, and the historical use of DSIP in compounded preparations. Each of these will be addressed in the FDA briefing document the agency posts ahead of the meeting, and pepi.ninja will summarize that briefing on the DSIP peptide page when it is released.

This page reports the sequence, the historical isolation, and the cited record of how DSIP arrived at PCAC. It does not predict the committee’s recommendation or the FDA’s listing decision.