What Is Ostarine (MK-2866)?

Ostarine, also known by its development code MK-2866 and the name Enobosarm, is a selective androgen receptor modulator (SARM) originally developed by GTx Inc. It was designed to investigate potential therapeutic applications in muscle wasting, osteoporosis, and cancer cachexia. Of all SARMs currently available for research, Ostarine has the most extensive human clinical trial history — having progressed through Phase I, Phase II, and Phase III clinical studies.

Ostarine binds selectively to androgen receptors in muscle and bone tissue with high affinity while demonstrating minimal interaction with androgen receptors in other tissues. Its relatively mild androgenic profile compared to other SARMs, combined with its extensive published clinical data, has established Ostarine as the most widely used reference compound in selective androgen receptor modulation research.

All products are sold strictly for laboratory and research purposes only. Ostarine is not approved by the FDA for human consumption.

Ostarine Product Specifications

Why Researchers Choose Our Ostarine

Who Purchases Ostarine for Research?

Ostarine (MK-2866) is purchased across a broad range of research contexts including:

• Independent researchers studying selective androgen receptor modulation
• University and private labs referencing Phase II and Phase III Ostarine trial data
• Muscle wasting and cancer cachexia researchers using Ostarine as a reference SARM
• Bone density researchers studying androgen receptor activity in skeletal tissue
• Researchers comparing Ostarine potency and selectivity against other SARMs
• Biohackers running documented biomarker and lean tissue protocol studies

All purchases are for laboratory and research use only. Ostarine is not approved by the FDA for human consumption and is not sold as a dietary supplement.

How Our Ostarine Compares

Frequently Asked Questions — Ostarine (MK-2866)

• Is Ostarine legal to buy in the US?

  Yes. Ostarine (MK-2866) is legal to purchase in the United States for research purposes. It is not currently a scheduled controlled substance under the DEA Controlled Substances Act. However, the SARMs Control Act has been introduced in Congress on multiple occasions and, if passed, would reclassify SARMs including Ostarine as Schedule III controlled substances alongside anabolic steroids.

  Ostarine is not FDA-approved for human consumption despite extensive clinical trial data. It is not legal to sell as a dietary supplement and cannot be marketed with health or performance claims. It must be purchased strictly for legitimate laboratory or scientific research use. Always verify the current regulatory status in your state before ordering.

• What is Ostarine used for in research?

  Ostarine has more published human clinical trial data than any other SARM. It has been studied across Phase I, II, and III clinical trials. Key research areas include:

  • Muscle wasting, cachexia, and sarcopenia in cancer and chronic disease models
  • Lean tissue preservation and anabolic activity studies in androgen-deficient subjects
  • Bone density and fracture risk reduction in osteoporosis research
  • Androgen receptor selectivity and tissue specificity comparisons
  • Stress urinary incontinence research — the primary focus of GTx Phase III trials
  • Reference compound studies comparing Ostarine against other SARMs and testosterone

  All research use must comply with applicable institutional and regulatory guidelines. Ostarine is not approved for any therapeutic application in humans despite its advanced clinical trial history.

• How does Ostarine compare to RAD140 and LGD-4033?

  Ostarine, RAD140, and LGD-4033 are all SARMs but differ significantly in potency, selectivity, androgenic suppression profile, and clinical research depth:

  • Ostarine (MK-2866): Mildest anabolic effect. Most extensive human clinical data of any SARM. Lowest suppression profile. Widest tissue selectivity research base. Used as the standard reference SARM in comparative studies.
  • LGD-4033 (Ligandrol): Significantly more potent anabolic effect than Ostarine at lower concentrations. Has Phase I and II human trial data. Higher androgenic suppression profile than Ostarine.
  • RAD140 (Testolone): Highest reported anabolic-to-androgenic ratio (~90:1) of the three in preclinical models. Less human trial data than both Ostarine and LGD-4033. Also studied for neuroprotective properties.

  For researchers seeking a well-documented reference SARM with the most peer-reviewed human data, Ostarine remains the primary benchmark compound in the SARM research field.

• What is the difference between Ostarine solution and Ostarine powder?

  Both formats contain the same compound — Ostarine (MK-2866) — at verified purity. The difference is in preparation and intended application:

  • Solution (25mg/ml in 50ml): Pre-measured liquid ready for immediate use in research protocols. No preparation required. Ideal for consistent dosing studies and standard administration schedules.
  • Powder (1g): Raw compound in lyophilized form. Suited for researchers who need to prepare custom concentrations, formulate capsules, or conduct gravimetric measurement studies requiring precise weighing.

  Both formats are independently tested and supplied with a batch-specific Certificate of Analysis confirming compound identity and purity percentage.

• How do I verify the purity of your Ostarine?

  Every batch of Ostarine 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 compound concentration at 25mg/ml
  • Mass spectrometry identity verification matching the correct molecular weight of MK-2866
  • Batch lot number that matches the label on the bottle you receive
  • Laboratory name and contact information for independent verification

  COAs are available for download directly on the product page without requiring an account or prior purchase. If your bottle’s lot number does not match the posted COA, contact us immediately for resolution.

• How fast does Ostarine ship and what are the delivery options?

  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 are shipped in plain, discreet packaging with no product labeling visible externally. 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 Ostarine?

  Ostarine solution and powder maintain stability under correct storage conditions:

  • Solution: Store at room temperature (15–25°C / 59–77°F), away from direct sunlight, heat sources, and humidity. Stable for up to 24 months under correct conditions. Refrigeration is not required and may cause precipitation in solution.
  • Powder: Store in a cool, dry, dark location in a tightly sealed container. Powder form typically maintains stability for 24–36 months when properly stored away from humidity and light.

  Each bottle is labeled with a manufacturing date and expiry date. Do not use the compound after the expiry date printed on the label or stated on the COA.

• Can I buy Ostarine in bulk quantities?

  Yes. Bulk and wholesale pricing is available for research institutions, private laboratories, and verified researchers requiring quantities above standard catalog listings. Both solution and powder formats are available for bulk ordering.

  Volume discount tiers are applied automatically at checkout for qualifying order sizes. For institutional purchase orders, custom invoicing, or high-volume requirements, contact us directly via the enquiry form with the following details:

  • Required quantity and preferred format (solution or powder)
  • Intended research application or institutional affiliation
  • Preferred delivery timeline and location

  All bulk orders are subject to the same independent third-party verification standards and include full COA documentation for every batch supplied.