NNZ-2591
NNZ-2591, also called ercanetide, is a synthetic cyclic glycine-proline analogue investigated for genetic neurodevelopmental disorders, including Phelan-McDermid syndrome.
At a glance
- Evidence stage
- Early human
- Regulatory status
- Investigational neurodevelopmental candidate; the registered phase 3 Phelan-McDermid study does not establish an approved use.
- Research context
- NNZ-2591, also called ercanetide, is a synthetic cyclic glycine-proline analogue investigated for genetic neurodevelopmental disorders, including Phelan-McDermid syndrome.
What this is
- NNZ-2591, also called ercanetide, is a synthetic cyclic glycine-proline analogue investigated for genetic neurodevelopmental disorders, including Phelan-McDermid syndrome.
What this isn't
- A recommendation to use, prepare, combine, or administer a product
- Evidence that a related molecule or a differently formulated product has the same effects
NNZ-2591, also called ercanetide, is a synthetic cyclic glycine-proline analogue investigated for genetic neurodevelopmental disorders, including Phelan-McDermid syndrome.
The proposed biology involves regulation of IGF-1 availability and downstream signaling relevant to synaptic function. This is a research rationale, rather than a demonstrated explanation for every behavioral change. The phase 2 publication concerns a defined genetic syndrome and should not be read as evidence for general cognitive enhancement or treatment of unrelated developmental conditions.
Evidence limits
How to read the evidence
The study's multiple rating scales, small sample, and unblinded caregiver and clinician assessments make the apparent benefit preliminary. The corrected table also matters when interpreting event frequencies. Evidence from this analogue cannot simply be substituted for trofinetide evidence: they are different compounds with different clinical programs and regulatory histories.
Sources appraised 2026-10-28. Educational information; not medical advice. Study findings apply to the populations, preparations and outcomes described.
External sources and citations
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