What Is NSI-189?

NSI-189 (also designated NSI-189 Phosphate in its salt form) is a novel synthetic compound originally developed by Neuralstem Inc. as part of a research program investigating neurogenesis — the process by which new neurons are generated in the brain. It was specifically investigated for its potential to stimulate hippocampal neurogenesis, targeting the dentate gyrus region of the hippocampus, an area associated with memory consolidation, spatial navigation, and mood regulation.

NSI-189 progressed through Phase I and Phase II human clinical trials conducted by Neuralstem, making it one of the few synthetic neurogenic research compounds with published human clinical data. The Phase I trial, published in the journal Translational Psychiatry, demonstrated NSI-189’s safety profile and neurogenesis-stimulating activity. The Phase II trial investigated its effects in major depressive disorder. NSI-189 remains one of the most unique and clinically researched synthetic neurogenic compounds available in the research market.

All products are sold strictly for laboratory and research purposes only. NSI-189 is not approved by the FDA for human consumption or therapeutic use.

NSI-189 Product Specifications

Why Researchers Choose Our NSI-189

What to Look for When Buying NSI-189 Online

NSI-189 is one of the more complex research compounds to source reliably. The two distinct forms — Phosphate and Free Base — have different properties, and the scarcity of high-quality suppliers means adulteration and mislabeling are genuine concerns. Before purchasing NSI-189 from any supplier, confirm these standards are in place.

• Form specified — Phosphate vs Free Base
  NSI-189 Phosphate and NSI-189 Free Base are not interchangeable. They have different molecular weights, solubility profiles, and dosing equivalencies. The COA must specify which form you are receiving — not simply list “NSI-189” without form designation.
• HPLC and Mass Spectrometry — both required
  HPLC confirms purity percentage. Mass spectrometry confirms compound identity by molecular weight. NSI-189 Phosphate (MW 488.50 g/mol) and Free Base (MW 397.49 g/mol) have distinct molecular weights that mass spectrometry can confirm precisely.
• Batch-specific COA from a named US laboratory
  Every batch must have a COA from an independently contactable, US-accredited laboratory tied to the exact batch lot number. Generic documents or COAs without a named, verifiable laboratory are not acceptable research-grade verification.
• US-manufactured — not Chinese bulk resold
  NSI-189 from unverified overseas sources without independent testing carries significant identity and purity risk. US-manufactured NSI-189 with domestic third-party testing provides traceable, auditable quality assurance for research use.
• Chiral purity confirmation where applicable
  NSI-189 contains a chiral center. The S-enantiomer is the form used in Neuralstem’s published clinical research. High-quality suppliers should confirm chiral purity — not simply overall compound purity — on the COA.

Who Purchases NSI-189 for Research?

NSI-189 is purchased across a specialized range of neurogenesis and cognitive research contexts including:

• Neurogenesis researchers studying hippocampal dentate gyrus neurogenesis models
• Neuroscience labs replicating and extending Neuralstem Phase I and II trial data
• Depression and mood disorder researchers studying neurogenic mechanisms
• Cognitive decline researchers investigating adult hippocampal neurogenesis
• Comparative neurogenic researchers benchmarking NSI-189 against other neurogenic compounds
• Biohackers running documented cognitive and neurogenic biomarker protocols

All purchases are for laboratory and research use only. NSI-189 is not approved by the FDA for human consumption and is not sold as a dietary supplement or therapeutic product.

How Our NSI-189 Compares

Frequently Asked Questions — Buy NSI-189

• Is NSI-189 legal to buy in the US?

  Yes. NSI-189 is legal to purchase in the United States for research purposes. It is not a scheduled controlled substance under the DEA Controlled Substances Act and is not regulated as a prescription drug or controlled nootropic under any current federal legislation.

  However, NSI-189 is not FDA-approved for human consumption or therapeutic use. It completed Phase I and Phase II human clinical trials under an Investigational New Drug (IND) application held by Neuralstem Inc. but has not received FDA approval. It may not be sold as a dietary supplement or marketed with health, mood, or cognitive performance claims. Our NSI-189 is sold strictly for laboratory and scientific research purposes only. Always verify the current regulatory status in your state before ordering.

• What is NSI-189 used for in research?

  NSI-189 is studied primarily as a synthetic neurogenic compound targeting hippocampal neurogenesis. It is one of the very few synthetic neurogenic compounds with published Phase I and Phase II human clinical data. Key research areas include:

  • Hippocampal neurogenesis and dentate gyrus volume studies
  • Major depressive disorder and neurogenic hypothesis of depression research
  • Cognitive function, memory consolidation, and learning research
  • Adult hippocampal plasticity and neuronal proliferation studies
  • Comparative neurogenic compound research against other neurogenesis stimulators
  • Mood regulation and hippocampal volume relationship investigations
  • Neurodegeneration and cognitive decline research in aging models

  All research use must comply with applicable institutional and regulatory guidelines. NSI-189 is not approved for any therapeutic application in humans.

• What is the difference between NSI-189 Phosphate and NSI-189 Free Base?

  NSI-189 Phosphate and NSI-189 Free Base are the same active compound in two different chemical forms. Understanding the distinction is essential for accurate research dosing and protocol design:

  • NSI-189 Phosphate: The phosphate salt form. Molecular weight approximately 488.50 g/mol. Higher molecular weight means that by weight, a given mass of NSI-189 Phosphate contains less active compound than the equivalent weight of Free Base. The form used in Neuralstem’s published Phase I and Phase II human clinical trials. Generally better water solubility than the Free Base form.
  • NSI-189 Free Base: The unsalted parent compound. Molecular weight approximately 397.49 g/mol. Contains a higher proportion of active compound per unit weight compared to the Phosphate form. Requires conversion factor when cross-referencing with Phosphate-based clinical trial dosing data. Solubility profile differs from the Phosphate form.

  When designing research protocols based on published Neuralstem clinical trial data, researchers should note that all published human data used the Phosphate form and apply the appropriate molecular weight conversion factor when using the Free Base form.

• What did the NSI-189 clinical trials find?

  NSI-189 completed two human clinical trials conducted by Neuralstem Inc.:

  • Phase I trial (published in Translational Psychiatry, 2015): A randomized, double-blind, placebo-controlled study in 24 healthy volunteers investigating safety, pharmacokinetics, and preliminary efficacy signals. NSI-189 demonstrated a favorable safety profile and showed signals consistent with hippocampal neurogenesis, including cognitive performance changes on standardized assessments.
  • Phase II trial (published in Molecular Psychiatry, 2021): A larger randomized controlled trial in patients with major depressive disorder. The primary endpoint of depressive symptom reduction did not reach statistical significance versus placebo. However, the trial showed statistically significant improvements on cognition-related secondary endpoints, consistent with the neurogenic mechanism of action.

  These trials establish NSI-189 as one of the few synthetic neurogenic compounds with published human safety data — a significant differentiator from most compounds in the neurogenic research space. All data referenced here is from published, peer-reviewed sources.

• How do I verify the purity of your NSI-189?

  Every batch of NSI-189 we stock has a corresponding Certificate of Analysis (COA) issued by an independent, US-accredited third-party laboratory. We do not use in-house testing or recycle documentation across batches.

  Each COA includes:

  • HPLC purity percentage confirming ≥99% purity
  • Mass spectrometry identity verification confirming the correct molecular weight for the specified form — Phosphate (488.50 g/mol) or Free Base (397.49 g/mol)
  • Form designation — Phosphate or Free Base — clearly stated
  • Batch lot number matching the label on your package
  • Laboratory name and contact information for independent verification

  COAs are available for download directly on the product page before purchase — no account or prior order required. If your package lot number does not match the posted COA, contact us immediately for resolution.

• How fast does NSI-189 ship after ordering?

  Orders placed before 2pm EST on business days ship the same day. Orders placed after 2pm EST or on weekends ship the next available business day.

  • Standard shipping: 2–4 business days via USPS or UPS depending on destination
  • Express shipping: 1–2 business days, selectable at checkout
  • Overnight delivery: Available on request for qualifying orders

  All orders ship in plain, discreet packaging with no product labeling visible on the outside. A tracking number is emailed immediately upon dispatch. We ship to all 50 US states. International shipping is not currently available.

• What is the shelf life and storage requirement for NSI-189?

  NSI-189 Phosphate and Free Base powder maintain stability under correct storage conditions:

  • Short-term storage (up to 3 months): Store at room temperature (15–25°C / 59–77°F) in the original sealed container, away from moisture, heat, and direct light. Keep tightly sealed when not in use.
  • Long-term storage (3 months and beyond): Refrigerate at 2–8°C (36–46°F) in the original sealed, light-protected container. Allow to reach room temperature before opening to prevent condensation entering the container. Do not freeze.
  • Humidity sensitivity: NSI-189 Phosphate in particular is sensitive to moisture absorption. Store with desiccant if operating in high-humidity environments.

  When stored correctly, NSI-189 powder typically maintains stability for 24 months from the manufacturing date. Each package is labeled with a manufacturing date and expiry date. Do not use after the stated expiry.

• Can I buy NSI-189 in bulk quantities?

  Yes. Bulk pricing is available for research institutions, university laboratories, and verified researchers requiring quantities above standard catalog listings. Both NSI-189 Phosphate and NSI-189 Free Base are available for bulk ordering.

  Volume discount tiers are applied automatically at checkout for qualifying order sizes. For institutional purchase orders, custom invoicing, or quantities above standard catalog levels, contact us directly via the enquiry form with the following details:

  • Required quantity in grams
  • Preferred form — Phosphate or Free Base
  • Intended research application or institutional affiliation
  • Any specific purity, packaging, or documentation requirements
  • Preferred delivery timeline and location

  All bulk orders include full batch-specific COA documentation and are subject to the same independent third-party verification standards as standard catalog purchases.