WARNING LETTER
ASN-LABS
MARCS-CMS 716459 —
September 09, 2025
Delivery Method:
VIA ELECTRONIC MAIL READ/DELIVERY RECEIPT REQUESTED
Product:
Drugs
Recipient:
ASN-LABS
1450 Ala Moana Blvd
Honolulu
,
HI
96814
United States
cs@asn-labs.com
Issuing Office:
Center for Drug Evaluation and Research (CDER)
United States
WARNING LETTER
September 9, 2025
ASN-LABS:
This letter is to advise you that the United States Food and Drug Administration (FDA) reviewed your website content at the internet address https://asn-labs.com in August 2025 and has observed that your website offers various compounded drug products, including retatrutide and semaglutide.
1
As described below, your retatrutide drug products are unapproved new drugs and misbranded drugs introduced or delivered for introduction into interstate commerce in violation of sections 505(a), 502(f)(1), 301(a) and 301(d) of the Federal Food, Drug, and Cosmetic Act (FDCA) [21 U.S.C. §§ 355(a), 352(f)(1), 331(a) and 331(d)]. In addition, your claims concerning compounded semaglutide products are false or misleading under sections 502(a) and 502(bb) of the FDCA [21 U.S.C. §§ 352(a) and 352(bb)] resulting in products being introduced or delivered for introduction into interstate commerce in violation of section 301(a) of the FDCA [21 U.S.C. § 331(a)].
A. Compounded Drug Products Under the FDCA
Section 503A of the FDCA describes the conditions under which human drug products compounded by a licensed pharmacist in a State licensed pharmacy or a Federal facility, or a licensed physician, qualify for exemptions from three sections of the FDCA: compliance with current good manufacturing practice (CGMP) (section 501(a)(2)(B)); labeling with adequate directions for use (section 502(f)(1)); and FDA approval prior to marketing (section 505) [21 U.S.C. §§ 351(a)(2)(B), 352(f)(1) and 355(a)].
2
Under section 503B(b) of the FDCA, a compounder can register as an outsourcing facility with FDA. Drug products compounded by or under the direct supervision of a licensed pharmacist in an outsourcing facility qualify for exemptions from the drug approval requirements in section 505 of the FDCA [21 U.S.C. § 355(a)], the requirement in section 502(f)(1) of the FDCA [21 U.S.C. § 352(f)(1)] that labeling bear adequate directions for use and the Drug Supply Chain Security Act requirements in section 582 of the FDCA [21 U.S.C. § 360eee-1] if the conditions in section 503B of the FDCA are met.
3
Among the conditions of sections 503A and 503B are restrictions on the bulk drug substances (active pharmaceutical ingredients or APIs) that may be used to compound human drug products. Under section 503A, one of the conditions that must be met for a compounded drug product to qualify for the exemptions is that, if the product is compounded using bulk drug substances, such bulk drug substances (I) comply with the standards of an applicable United States Pharmacopeia (USP) or National Formulary (NF) monograph, if a monograph exists, and the USP chapter on pharmacy compounding; (II) if such a monograph does not exist, be components of drugs approved by the Secretary; or (III) if such a monograph does not exist and the drug substance is not a component of a drug approved by the Secretary, appear on a list developed by the Secretary through regulation (“503A bulks list”) (section 503A(b)(1)(A)(i) of the FDCA [21 U.S.C. § 353a(b)(1)(A)(i)]).
Similarly, one of the conditions that must be met for a drug product compounded by an outsourcing facility to qualify for the exemptions under section 503B of the FDCA, is that the outsourcing facility does not compound drug products using bulk drug substances unless the bulk drug substances that are used appear on a list established by the Secretary identifying bulk drug substances for which there is a clinical need (“503B bulks list”), or the compounded drug appears on the drug shortage list in effect under section 506E of the FDCA at the time of compounding, distribution, and dispensing (section 503B(a)(2)(A)(i) of the FDCA [21 U.S.C. § 353b(a)(2)(A)]).
B. Failure to Meet the Conditions of Sections 503A and 503B
Your compounded retatrutide drug products fail to meet the conditions of sections 503A and 503B. Drug products compounded using retatrutide are not eligible for the exemptions provided by section 503A, because retatrutide is not the subject of an applicable USP or NF monograph, is not a component of an FDA-approved human drug, and does not appear on the 503A bulks list.
4
Drug products compounded using retatrutide are not eligible for the exemptions provided by section 503B, because retatrutide does not appear on the 503B bulks list, and is not used to compound a drug that appears on the drug shortage list.
5
Because your compounded retatrutide drug products have not met all of the conditions of either section 503A or section 503B, they are not eligible for the exemptions in those sections from certain requirements of the FDCA, including FDA approval requirements of section 505 and the requirement under section 502(f)(1) that labeling bear adequate directions for use.
Specific violations are described below.
C. Violations of the FDCA
Unapproved New Drugs & Misbranded Drugs
There are no FDA-approved applications on file for your compounded retatrutide drug product. Under sections 505(a) and 301(d) of the FDCA [21 U.S.C. §§ 355(a) and 331(d)] a new drug may not be introduced into or delivered for introduction into interstate commerce unless an application approved by FDA under section 505 of the FDCA is in effect for the drug. Marketing of these products, or other applicable products, without an approved application violates these provisions of the FDCA.
Furthermore, your compounded retatrutide drug products are intended for conditions not amenable to self-diagnosis and treatment by individuals who are not medical practitioners; therefore, adequate directions for use cannot be written so that a layman can use these products safely for their intended use. Consequently, their labeling fails to bear adequate directions for their intended use causing them to be misbranded under section 502(f)(1) of the FDCA.
6
introduction or delivery for introduction into interstate commerce of these products therefore violates section 301(a) of the FDCA.
False or Misleading Claims
Under section 502(a) of the FDCA [21 U.S.C. § 352(a)] a drug is misbranded if its labeling is false or misleading in any particular. Furthermore, under section 502(bb) of the FDCA [21 U.S.C. § 352(bb)], a compounded drug is misbranded if its advertising or promotion is false or misleading in any particular.
The following claims concerning compounded semaglutide products appear on your website:
•  “The same active ingredient as Wegovy and Ozempic”
•  “Semaglutide is the generic drug in Ozempic (injectable) and Rybelsus (oral) diabetes control medications, and Wegovy (injectable) weight loss medication.”
Compounded drug products are not FDA-approved. Your claims imply that your products are the same as an FDA-approved product when they are not. As a result, these claims are false or misleading and your products are therefore misbranded under sections 502(a) and 502(bb) of the FDCA [21 U.S.C. §§ 352(a) and (bb)].
The introduction or delivery for introduction into interstate commerce of these misbranded products is a prohibited act under section 301(a) of the FDCA [21 U.S.C. § 331(a)]. The claims identified in this letter put you on notice of our concerns but do not represent an exhaustive list of misbranding violations.
7
D. Conclusion
For the reasons discussed above, your compounded retatrutide drug products are unapproved new drugs and misbranded drugs introduced or delivered for introduction into interstate commerce in violation of sections 505(a), 502(f)(1), 301(a) and 301(d) of the FDCA [21 U.S.C. §§ 355(a), 352(f)(1), 331(a) and 331(d)]. In addition, your claims concerning compounded semaglutide drug products are false or misleading under sections 502(a) and 502(bb) of the FDCA [21 U.S.C. §§ 352(a) and 352(bb)] resulting in products being introduced or delivered for introduction into interstate commerce in violation of section 301(a) of the FDCA [21 U.S.C. § 331(a)]. Please be advised, the receipt in interstate commerce of misbranded drugs, and the delivery or proffered delivery thereof, is also a violation of section 301(c) of the FDCA [21 U.S.C. § 331(c)].
As previously stated, 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 operations comply with all requirements of federal law, including FDA regulations.
You should take immediate action to address any violations (including, for example, ceasing and desisting from using the language cited above that misbrands the product). Failure to adequately address any violations may result in legal action without further notice, including, without limitation, seizure and injunction.
Within fifteen (15) working days of receipt of this letter, please provide a written response to the Office of Compounding Quality and Compliance (OCQC) within the Center for Drug Evaluation and Research (CDER)’s Office of Compliance describing the specific steps you have taken to address any violations. Please include an explanation of each step being taken to prevent the recurrence of violations, as well as copies of related documentation. This letter notifies you of our concerns and provides you an opportunity to address them. If you believe your products are not in violation of the FDCA, include your reasoning and any supporting information for our consideration. If you cannot completely address this matter within fifteen (15) working days, state the reason for the delay and the time within which you will do so.
If you are not located in the U.S., please note that products that appear to be misbranded or unapproved new drugs may be detained or refused admission. We may advise the appropriate regulatory officials in the country from which you operate that your products referenced above appear to be misbranded and unapproved new drugs that cannot be legally sold to consumers in the U.S.
All correspondence should include a subject line that clearly identifies the submission as a Response to Warning Letter. If you have questions regarding the contents of this letter, please contact compoundinginspections@fda.hhs.gov.
Sincerely,
/s/
George Tidmarsh, M.D., Ph.D. Director
Center for Drug Evaluation and Research
U.S. Food and Drug Administration
1
The retatrutide, semaglutide, and tirzepatide products offered on your website are drugs within the meaning of section 201(g) of the FDCA [21 U.S.C. § 321(g)] because they are intended for use in the diagnosis, cure, mitigation, treatment, or prevention of diseases and/or because they are intended to affect the structure or any function of the body. Further, they are “new drugs” within the meaning of section 201(p) of the FDCA [21 U.S.C. § 321(p)] because they are not generally recognized as safe and effective for their labeled uses.
2
We remind you that there are conditions other than those discussed in this letter that must be satisfied to qualify for the exemptions in section 503A of the FDCA.
3
We remind you that there are conditions, other than those discussed in this letter, that must be satisfied to qualify for the exemptions in section 503B of the FDCA.
4
These substances are also not eligible for the policy applicable to certain bulk drug substances described in the final guidance titled, Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A of the Federal Food, Drug, and Cosmetic Act. This guidance describes FDA’s interim regulatory policy for State-licensed pharmacies, Federal facilities, and licensed physicians that compound human drug products using bulk drug substances that do not otherwise meet the conditions of section 503A(b)(1)(A)(i) while the 503A bulks list is being developed. Specifically, the guidance sets out the conditions under which FDA does not intend to take action against a State-licensed pharmacy, Federal facility, or licensed physician for compounding a drug product using a bulk drug substance that is not the subject of an applicable USP or NF monograph or a component of an FDA- approved drug, until the substance is identified in a final rule as included or not included on the 503A bulks list. These conditions include that the substance may be eligible for inclusion on the 503A bulks list, was nominated with adequate support for FDA to evaluate it and has not been identified by FDA as a substance that appears to present significant safety risks pending further evaluation. For additional information, see the guidance at http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/UCM469120.pdf.
5
These substances are also not eligible for the policy applicable to certain bulk drug substances described in the final guidance titled, Interim Policy on Compounding Using Bulk Drug Substances Under Section 503B of the Federal Food, Drug, and Cosmetic Act (Revision 1). This guidance describes FDA’s interim regulatory policy for outsourcing facilities registered under section 503B of the FDCA while the 503B bulks list is being developed. Specifically, the guidance sets out conditions under which FDA generally does not intend to take action against an outsourcing facility for compounding a drug product using a bulk drug substance that is not included on the 503B list where the drug product also does not appear on the drug shortage list in effect under section 506E at the time of compounding, distribution, and dispensing. These conditions include that the drug product appears on “503B Category 1 – Bulk Drug Substances Under Evaluation”, which includes substances that may be eligible for inclusion on the 503B bulks list, was nominated with adequate support for FDA to evaluate it and has not been identified by FDA as a substance that appears to present significant safety risks pending further evaluation. For additional information, see the guidance at http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/UCM469122.pdf
6
Your compounded retatrutide drug products are not exempt from the requirements of section 502(f)(1) of the FDCA by regulations issued by the FDA (see, e.g., 21 CFR 201.115).
7
Overstatements of efficacy or minimization of risk are of particular concern and may constitute misbranding.
Content current as of:
09/16/2025
Regulated Product(s)
Drugs