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WARNING LETTER

December 12, 2025

RE: 719433

Fernando Arias:

This letter is to advise you that the U.S. Food and Drug Administration (FDA) reviewed your website at https://primesportsnutrition.com/ in November 2025. The FDA has observed that you offer products marketed on your firm’s website as selective androgen receptor modulators (SARMs) including, but not limited to, “LGD-4033” (also referred to on your website as “Ligandrol”), “RAD-140” (also referred to on your website as “Testolone”), “MK-677” (also referred to on your website as “Ibutamoren”), and “S-23” (hereinafter products marketed as SARMs) for sale in the United States. Based on our review, these products are unapproved new drugs under section 505(a) of the Federal Food, Drug, and Cosmetic Act (FD&C Act), 21 U.S.C. 355(a). As explained further below, introducing or delivering these products for introduction into interstate commerce violates sections 301(d) and 505(a) of the FD&C Act, 21 U.S.C. 331(d) and 355(a).

FDA has safety concerns about products that contain SARMs. Life-threatening reactions, including liver toxicity, have occurred in people taking products containing SARMs. SARMs also have the potential to increase the risk of heart attack and stroke.¹

Despite statements on your product labeling marketing some of your products as a “RESEARCH COMPOUND” and “NOT FOR HUMAN CONSUMPTION,” evidence obtained from your product labeling, including your website, establishes that your products are intended to be drugs for human use. Based on a review of your website, your products marketed as SARMs are drugs under section 201(g)(1) of the FD&C Act, 21 U.S.C. 321(g)(1), because they are intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease, and/or intended to affect the structure or any function of the body. Examples from your product labeling, including on your website, that provide evidence of the intended use (as defined in 21 CFR 201.128) of these products as drugs include, but may not be limited to, the following:

LGD-4033 Ligandrol

On the webpage https://primesportsnutrition.com/products/lgd-4033-galactic-plus:

• “Looking To Build Lean Mass And Improving Strength While Maximizing Your Fat Loss Potential. LGD-4033 Has You Covered. LGD Is A Selective Androgen Receptor Modulator (SARM) That Usually Goes By The Name Ligandrol. It’s Known For Its Muscle Mass And Strength Increasing Properties That Actually Don’t Come With The Anabolic Side Effects. This Is What Makes It So Popular With Bodybuilders And Athletes. Ligandrol Acts Similar To An Anabolic Based Substance. It Has The Ability To Rapidly Increase Muscle Mass While Reducing Overall Body Fat. Increased Muscle Mass And An Increase In Strength Are Both Results Of The Selective Activation Of Androgen Receptors In The Muscles.”
• “KEY BENEFITS
  o Improves Muscle Mass
  o Improve Stamina
  o Burns Body Fat
  o Boosts Testosterone”

RAD-140 Testolone

On the webpage https://primesportsnutrition.com/products/galactic-plus-duo-mk677-rad140-1?_pos=4&_sid=9711d0e06&_ss=r:

• “RAD140 + MK677 is A Very Popular Pairing.”
• “Many Across The World Are Admiring RAD-140 For Countless Reasons. Testolone RAD140 Was Designed As A Safer Alternative To Anabolics. This Highly Anabolic Compound Promotes Increases In Muscle Mass And Is Second To None For Mimicking The Effects Of Natural Testosterone.”
• “Benefits Of Testolone (RAD140)
  o Anabolic To Androgenic Ratio of 90:1
  o Improves Libido And Sexual Performance
  o Best SARM For Muscle Growth And Size.
  o Reduces Fat And Increases Muscle Mass.
  o Ideal To Enhance Body Composition.
  o Rapid Muscle Recovery”
• “Medical Studies Have Demonstrated (And As Confirmed By Online Reviews About Testolone) That RAD-140 Is Highly Effective To Treat Degenerative Conditions Like Alzheimer's Disease. It Is Equally Effective To Provide Relief To Subjects With Androgenic Deficiencies.”
• “Individuals Treated With Testolone Have Reported Improvements In The Levels Of Sexual Development And Function.”
• “The Use Of Testolone Is Associated By RAD-140 Users With Dramatic Relief From Muscle Wasting Or Loss Or Muscle Tissue, Weakness, And Fatigue That Makes The Entire Otherwise-Complicated Processes Of Healing And Recovery Easy And Quick.”
• “RAD-140 Users Can Expect Dramatic Fat Loss And Gain 5-15 Lbs Lean Muscle Mass Gains In As Short As Four To Six Weeks.”

MK-677 Ibutamoren

On the webpage https://primesportsnutrition.com/products/galactic-plus-duo-mk677-rad140-1?_pos=4&_sid=9711d0e06&_ss=r:

• “Benefits Of Ibutamoren (MK-677)
  o Increases Muscle Mass and Strength
  o Improves Tissue Regeneration
  o Increases Growth Hormone Levels
  o Clinically Proven GH Elevator
  o Enhanced Vitality And Faster Recovery
  o Reduces Body Fat
  o Increases Sleep Quality And Rapid Eye Movement (REM) Sleep
  o Increases Insulin-Like Growth Factor 1 (IGF-1)
  o Improves Basal Metabolic Rate”
• “MK-677 + RAD 140 is Normally Used 12 Weeks”

S-23

On the webpage https://primesportsnutrition.com/products/s23-galactic-plus-1:

• “Looking To Boost Strength While Obliterating Fat? Let Us Introduce You To S23! One Of The Most Potent SARMs On The Market, Some Say That S-23 Is The Closest Thing To Conventional Steroids That You Can Get. An Excellent Cutting Compound, It Boosts Fat Loss Whilst Offering Impressive Lean, Dry Gains. This Compound Is Renowned For Developing A Dense, Hard Aesthetic With No Water Retention. If You’re Looking For Grainy-Looking Muscles, Then You Should Definitely Consider S-23.”
• “KEY BENEFITS
  o Muscle Mass Increase
  o Fat Loss
  o Increased Endurance
  o Recover Times Are Shorter.”

Your products marketed as SARMs are “new drugs” under section 201(p) of the FD&C Act, 21 U.S.C. 321(p), because they are not generally recognized as safe and effective (GRASE) for use under the above-described conditions prescribed, recommended, or suggested in their labeling. With certain exceptions not applicable here, a new drug may not be introduced or delivered for introduction into interstate commerce without an approved application from FDA in effect, as described in section 505(a) of the FD&C Act, 21 U.S.C. 355(a). No approved applications pursuant to section 505 of the FD&C Act, 21 U.S.C. 355, are in effect for these products. Accordingly, these products are unapproved new drugs. The introduction or delivery for introduction into interstate commerce of these unapproved new drug products violates sections 301(d) and 505(a) of the FD&C Act, 21 U.S.C. 331(d) and 355(a).

Conclusion

The violations cited in this letter are not intended to be an all-inclusive statement of violations that may exist in connection with your products. You are responsible for investigating and determining the causes of any violations and for preventing their recurrence or the occurrence of other violations. It is your responsibility to ensure that your firm complies with all requirements of federal law, including FDA regulations.

This letter notifies you of our concerns and provides you an opportunity to address them. Failure to adequately address this matter may lead to regulatory or legal action including, without limitation, seizure and injunction.

Please notify FDA in writing, within fifteen working days of receipt of this letter, of the specific steps you have taken to correct any violations. Include an explanation of each step being taken to prevent the recurrence of violations, as well as copies of related documentation. If you believe that your products are not in violation of the FD&C Act, include your reasoning and any supporting information for our consideration. If you cannot complete corrective action within fifteen working days, state the reason for the delay and the time within which you will complete the correction.

Your response should be sent to U.S. Food and Drug Administration, CDER/OC/Office of Unapproved Drugs and Labeling Compliance by email to FDAAdvisory@fda.hhs.gov. Please include your firm name and the unique identifier “719433” in the subject line of the email.

Sincerely,
/S/

Tina Smith, M.S.
Captain, U.S. Public Health Service
Director
Office of Unapproved Drugs and Labeling Compliance
Office of Compliance
Center for Drug Evaluation and Research
Food and Drug Administration

______________________________

1 See https://www.fda.gov/consumers/consumer-updates/fda-warns-use-selective-androgen-receptor-modulators-sarms-among-teens-young-adults.