How to Use NNZ-2591
Complete guide to NNZ-2591 dosing, administration, timing, and protocol recommendations.
Quick Overview
NNZ-2591 is Neuren Pharmaceuticals' second drug, a synthetic analog of cyclic glycine-proline (cGP), a small ring-shaped molecule the body makes when it breaks down IGF-1. It is taken by mouth and is being developed for rare childhood neurodevelopmental disorders: Phelan-McDermid syndrome is furthest along, with the first-ever phase 3 trial in that disease started in late 2025, and Angelman and Pitt Hopkins syndromes behind it. Phase 2 results looked encouraging, but they were small open-label studies, so nobody knows yet whether it truly works.
Dosing Guidelines
Common Dose
12 mg/kg twice daily (phase 2 target trial dose)
Frequency
Twice daily
Dose Range
4-12 mg/kg twice daily (trial titration)
Note: These are clinical trial doses in children with specific genetic syndromes, titrated under medical supervision. They are not recommendations. There is no approved product, and nothing sold outside trials has been verified as the real compound.
Administration Method
Oral liquid
Best Time to Take
Twice daily (trial schedule)
Trials give it twice daily by mouth. No timing relative to sleep or meals has been established.
Protocol Duration
13 weeks in phase 2 and phase 3 trials, with 12-month open-label extensions
Possible Side Effects
Not everyone experiences these. Individual responses vary.
- •Psychomotor hyperactivity (most common in the Phelan-McDermid trial)
- •Decreased appetite
- •Fever
- •Sleepiness
- •Mostly mild to moderate events in phase 2
Frequently Asked Questions
What is the recommended dose for NNZ-2591?
12 mg/kg twice daily (phase 2 target trial dose)
How do you administer NNZ-2591?
Oral liquid
When is the best time to take NNZ-2591?
Twice daily (trial schedule)
How long should you use NNZ-2591?
13 weeks in phase 2 and phase 3 trials, with 12-month open-label extensions
This information is for educational purposes only. Always consult with a healthcare professional before using any peptide. Dosing information is based on research literature and community reports, not medical advice.