WARNING LETTER
Macau-Union Pharmaceutical Limited
MARCS-CMS 724506 —
May 29, 2026
Delivery Method:
Via Electronic Mail - Return Receipt Requested
Product:
Drugs
Recipient:
Recipient Name
Mr. Kin Va Choi
Recipient Title
General Manager
Macau-Union Pharmaceutical Limited
3 - 3A Rua Cinco Do Bairro Da Areia Preta
Room B 1/F, Industrial Veng Fong
Macao SAR China
Issuing Office:
Center for Drug Evaluation and Research (CDER)
United States
Warning Letter
320-26-83
May 29, 2026
Dear Mr. Choi:
The United States Food and Drug Administration (FDA) inspected your drug manufacturing facility, Macau-Union Pharmaceutical Limited, FEI 3011219786, at 3-3A Rua Cinco Do Bairro Da Areia Preta, Room B 1/F, Industrial Veng Fong, from December 15 to 17, 2025.
This warning letter summarizes significant violations of Current Good Manufacturing Practice (CGMP) regulations for finished pharmaceuticals. See Title 21 Code of Federal Regulations (CFR), parts 210 and 211 (21 CFR parts 210 and 211).
Because your methods, facilities, or controls for manufacturing, processing, packing, or holding do not conform to CGMP, your drug products are adulterated within the meaning of section 501(a)(2)(B) of the Federal Food, Drug, and Cosmetic Act (FD&C Act), 21 U.S.C. 351(a)(2)(B).
In addition, “Bamboo Pharmacy® Mobility penetrating muscle & joint rub” and “Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub” are unapproved new drugs introduced or delivered for introduction into interstate commerce in violation of section 505(a) and 301(d) of the FD&C Act, 21 U.S.C. 355(a), 331(d). Additionally, these products are misbranded under section 502(ee) of the FD&C Act, 21 U.S.C. 352(ee). Introduction or delivery for introduction of misbranded products into interstate commerce is prohibited under section 301(d) and (a) of the FD&C Act, 21 U.S.C. 331(d) and (a). These violations are described in more detail below.
We reviewed your February 2, 2026, response to our Form FDA 483 in detail.
CGMP Violations
During our inspection, our investigators observed specific violations including, but not limited to, the following.
1. Your firm failed to have, for each batch of drug product, appropriate laboratory determination of satisfactory conformance to final specifications for the drug product, including the identity and strength of each active ingredient, prior to release, and for each batch of drug product required to be free of objectionable microorganisms, appropriate laboratory testing, as necessary (21 CFR 211.165(a) and 211.165(b)).
Your firm did not adequately test your over-the-counter (OTC) drug products prior to release and distribution to the U.S. market. Specifically, your firm failed to test the identity and strength of each active ingredient before releasing the drug products. Your firm also failed to perform adequate microbiological testing on each batch of your drug products prior to release. You confirmed to our investigator that you lacked procedures for testing your finished drug products, and you could only provide evidence of finished drug product testing for appearance and weight.
In your response, you commit to requiring testing for all drug products for the U.S. market, including identity verification, assay, microbial limits, and critical quality attributes. You also included summary test reports for batches shipped to the U.S. These reports contained both chemical and microbial test results.
Your response is inadequate because you failed to provide supporting documentation for corrective actions. Additionally, the analytical reports provided lack specifications and show results for your active ingredients
(b)(4)
. The analyses found that these active ingredients were below the drug product labeled concentrations but offered no scientific justification or explanation. Sub potency versus the labeled concentration is also a violation of section 501(c) in that the drug product’s quality falls below that which it purports to possess. Further, your microbiological reports reference “Modified United States Pharmacopeia” (USP) methods (e.g. <61> and <62>); however, your response lacks adequate documentation describing the specific modifications made to the compendial USP methods.
Testing is essential to ensure that the drug products you manufacture conform to all pre-determined quality attributes appropriate for their intended use. Because your firm lacked adequate testing of each batch of your drug products, you do not know whether the drug products conform to all appropriate finished drug product specifications and are suitable for release to consumers.
In response to this letter, provide:
A list of chemical and microbial specifications, including test methods used to analyze each batch of your drug products before a batch disposition decision.
o An action plan and timelines for conducting full chemical and microbiological testing of retain samples to determine the quality of all batches of drug product distributed to the United States that are within expiry as of the date of this letter.
o A summary of all results obtained from testing retain samples from each batch. If such testing reveals substandard quality drug products, take rapid corrective actions, such as notifying customers and drug product recalls.
o Complete microbiological testing results per USP <61> and <62> as written. Provide justification for any modified microbiological test method with validation data.
o A comprehensive objectionable organism testing panel appropriate for topical OTC drug products including scientific rationale for microbiological specifications
o Corrective actions to ensure no drug product is released without complete finished drug product testing.
2. Your firm failed to test samples of each component for identity and conformity with all appropriate written specifications for purity, strength, and quality. Your firm also failed to validate and establish the reliability of your component supplier’s test analyses at appropriate intervals (21 CFR 211.84(d)(1) and 211.84(d)(2)).
Your firm failed to test incoming active pharmaceutical ingredients (APIs) (e.g.
(b)(4)
) and other components used to manufacture your OTC drug products to determine their identity, purity, strength, and other appropriate quality attributes. Additionally, you relied on your suppliers’ certificates of analysis (COA) without verifying your supplier’s test results at appropriate intervals.
In your response, you committed to implementing an identity testing program for all incoming components to align with USP requirements and to retrospectively verify the identity of the active ingredients
(b)(4)
. In addition, you will establish a supplier audit procedure to verify that suppliers’ test methods and COA results to ensure compliance with USP standards.
Your response is inadequate because you failed to provide supporting documentation demonstrating adequate implementation of the proposed corrective actions. You also do not mention retrospective testing for the active ingredients
(b)(4)
. Additionally, you did not include your interim plans to mitigate risks to drug products during the implementation of these corrective actions.
Without adequate testing, you do not have scientific evidence that the components conform to appropriate specifications prior to use in the manufacture of your drug products. As a manufacturer, you have a responsibility to sample, test, and examine drug components before use in production to assure adequate quality.
In response to this letter, provide:
A comprehensive, independent review of your material system including, but not limited to:
o evaluating all suppliers of materials (components, containers, and closures) to determine if they are reliable and appropriately qualified
o an assessment of all materials to determine if they are consistently of acceptable quality
o a review to ensure assigned expiration or retest dates are appropriate (supported by data)
o adequacy of the supplier qualification program and its selection, qualification, and disqualification provisions.
Based on a thorough review, provide a summary of your systems corrective action and preventive action (CAPA) plan to remediate the vendor qualification program and prevent use of unsuitable components, containers, and closures.
The chemical and microbiological quality control specifications you use to test and release each incoming batch of component for use in manufacturing.
A description of how you will test each component batch for conformity with all appropriate specifications for identity, strength, quality, and purity. If you intend to accept any results from your supplier’s COA instead of testing each component batch for strength, quality, and purity, specify how you will robustly establish the reliability of your supplier’s results through initial validation as well as periodic re-validation. In addition, include a commitment to always conduct at least one specific identity test for each incoming component batch.
A summary of results obtained from testing all components to evaluate the reliability of the COA from each component manufacturer. Include your SOP that describes this COA validation program.
A summary of your program for qualifying and overseeing contract facilities that test the components and drug products you manufacture.
3. Your firm failed to establish adequate written procedures for production and process control designed to assure that the drug products you manufacture have the identity, strength, quality, and purity they purport or are represented to possess, and your firm’s quality control unit did not review and approve those procedures, including any changes (21 CFR 211.100(a)).
Your firm lacks process validation studies to demonstrate reproducibility and control of your manufacturing processes to ensure uniform drug product quality. Additionally, your cleaning procedures for shared equipment are inadequate. You have not demonstrated that they enable operators to clean each equipment type reproducibly and effectively.
In your response, you committed to conducting full process validation for U.S. drug products along with establishing a comprehensive in-process testing program. You will develop a shared equipment cleaning validation protocol to validate cleaning effectiveness. Additionally, you will install a new
(b)(4)
system with monitoring capabilities and revise your
(b)(4)
management procedure to ensure that cleaning water meets
(b)(4)
USP standards.
Your response is inadequate because you failed to provide supporting documentation demonstrating adequate implementation of the proposed corrective actions. Additionally, you did not include a risk assessment of released drug products or provide any interim manufacturing plans to mitigate risks to drug products during the implementation of your corrective actions.
Process validation evaluates the soundness of design and state of control of a process throughout its lifecycle. Each significant stage of a manufacturing process must be designed appropriately and assure the quality of raw material inputs, in-process materials, and finished drugs. Process qualification studies include intensive monitoring and testing throughout each significant process stage to characterize intra-batch variation and evaluate batches to determine whether an initial state of control has been established.
See FDA’s guidance document Process Validation: General Principles and Practices for general principles and approaches that FDA considers appropriate elements of process validation at https://www.fda.gov/media/71021/download.
In response to this letter, provide:
A detailed summary of your validation program for ensuring a state of control throughout the drug product lifecycle, along with associated procedures. Describe your program for process performance qualification (PPQ), and ongoing monitoring of both intra-batch and inter-batch variation to ensure a continuing state of control.
A timeline for performing appropriate PPQ for each of your marketed drug products. Also provide a risk assessment and any follow-up actions to be taken for the distributed drug products produced without performing any process validation studies.
Process performance protocol(s) and written procedures for qualification of equipment and facilities.
A detailed program for designing, validating, maintaining, controlling and monitoring each of your manufacturing processes that include vigilant monitoring of intra-batch and inter-batch variation to ensure an ongoing state of control. Also, include your program for qualification of your equipment and facility.
Appropriate improvements to your cleaning validation program, with special emphasis on incorporating conditions identified as worst case in your drug manufacturing operation. This should include but not be limited to identification and evaluation of all worst-case:
o Drugs with higher toxicities
o Drugs with higher drug potencies
o Drugs of lower solubility in their cleaning solvents
o Drugs with characteristics that make them difficult to clean
o Swabbing locations for areas that are most difficult to clean
o Maximum hold times before cleaning
In addition, describe the steps that must be taken in your change management system before introduction of new manufacturing equipment or a new drug product.
A summary of updated standard operating procedures that ensure an appropriate program is in place for verification and validation of cleaning procedures for drug products, processes, and equipment.
4. Your firm failed to assure that the drug product bore an expiration date that was supported by appropriate stability testing (21 CFR 211.137(a)).
You failed to establish an adequate stability testing program to support the labeled expiration date on your distributed drug products in the U.S. market. There is no assurance that your OTC drug products will remain acceptable throughout the labeled
(b)(4)
expiry period without an ongoing stability program.
In your response, you committed to establishing a stability testing program “in compliance with USP <1150>.” You also commit to test identity and strength of the active ingredients, related substances, microbial limits, appearance, and viscosity at designated time intervals.
Your response is inadequate because your it lacked sufficient scientific evidence to ensure that your drug products will meet proposed specifications and retain their quality attributes throughout labeled expiry. Additionally, you did not conduct or provide a risk assessment for drug products currently on the market without adequate stability testing to support the labeled expiration date.
Without appropriate stability data, you cannot ensure your drug products meet established specifications and all pre-determined quality criteria throughout their assigned shelf-life.
In response to this letter, provide a comprehensive, independent assessment CAPA plan to ensure the adequacy of your stability program. Your remediated program should include, but not be limited to:
Stability-indicating methods
Stability studies for each drug product in its marketed container-closure system before distribution is permitted
An ongoing program in which representative batches of each drug product are added each year to the program to determine if the shelf-life claim remains valid
Detailed definition of the specific attributes to be tested at each station (timepoint)
All procedures that describe these and other elements of your remediated stability program
CGMP Consultant Recommended
Based upon the nature of the violations we identified at your firm, you should engage a consultant qualified as set forth in 21 CFR 211.34 to evaluate your operations and to assist your firm in meeting CGMP requirements. The qualified consultant should also perform a comprehensive six-system audit of your entire operation for CGMP compliance and evaluate the completion and efficacy of your CAPAs before you pursue resolution of your firm’s compliance status with FDA.
Your use of a consultant does not relieve your firm’s obligation to comply with CGMP. Your firm’s executive management remains responsible for resolving all deficiencies and systemic flaws to ensure ongoing CGMP compliance.
Unapproved New Drug and Misbranding Violations
“Bamboo Pharmacy® Mobility penetrating muscle & joint rub” and “Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub” are drugs as defined by section 201(g)(1)(B) of the FD&C Act, 21 U.S.C. 321(g)(1)(B) because they are intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease, and/or under section 201(g)(1)(C) of the FD&C Act, 21 U.S.C. 321(g)(1)(C) because they are intended to affect the structure or any function of the body.
Examples from the product labels that provide evidence of the intended uses (as defined in 21 CFR 201.128) of the products as drugs include, but may not be limited to, the following:
“Bamboo Pharmacy® Mobility penetrating muscle & joint rub”
“
DRUG FACTS . . . Uses:
For the temporary relief of minor aches and pains of muscles and joints due to ■arthritis ■strains ■bruises ■sprains ■simple backache” [from the product label]
“Natural herbs to Promote Healing Improve Circulation Reduce Inflammation” [from the product label]
“Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub”
“
DRUG FACTS . . . Uses:
For the temporary relief of minor aches and pains of muscles and joints due to■¦arthritis ■strains ■bruises ■sprains ■simple backache” [from the product label]
“Natural herbs to Promote Healing Improve Circulation Reduce Inflammation” [from the product label]
Unapproved New Drug Violations
Based on the above labeling evidence, “Bamboo Pharmacy® Mobility penetrating muscle & joint rub” and “Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub” are intended for use as external analgesic drug products, among other intended uses. As described below, these drug products are unapproved new drugs marketed in violation of sections 505(a) and 301(d) of the FD&C Act, 21 U.S.C 355(a) and 331(d).
A drug product is a “new drug” within the meaning of section 201(p) of the FD&C Act, 21 U.S.C. 321(p), if it is not generally recognized as safe and effective (GRASE) for use under the conditions prescribed, recommended, or suggested in its 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 FDA-approved applications pursuant to section 505 of the FD&C Act, 21 U.S.C. 355, are in effect for these drug products identified above.
Under section 505G of the FD&C Act, certain nonprescription drugs marketed without an approved application —commonly referred to as "OTC monograph drugs"—may be legally marketed if they meet applicable requirements. With respect to nonprescription external analgesic drug products, such as your “Bamboo Pharmacy® Mobility penetrating muscle & joint rub” and “Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub,” in order to be GRASE and not new drugs, the products must, among other things, conform to the conditions in the applicable OTC monograph, here M017: External Analgesic Drug Products for Over-the-Counter Human Use.
1
However, “Bamboo Pharmacy® Mobility penetrating muscle & joint rub” and “Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub” do not conform to the conditions specified in M017 for the reasons described below.
Specifically, the labeling for “Bamboo Pharmacy® Mobility penetrating muscle & joint rub” and “Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub” includes intended use claims that are not permitted under M017. For example, claims that the products “…Promote Healing Improve Circulation Reduce Inflammation” go beyond the allowed general intended uses for an external analgesic drug product and do not conform with M017.50(b).
Furthermore, as formulated “Bamboo Pharmacy® Mobility penetrating muscle & joint rub” and “Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub” includes active ingredients that are not permitted by M017.
2
For example, the product labels for “Bamboo Pharmacy® Mobility penetrating muscle & joint rub” and “Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub” state that the products are formulated with “Natural herbs to Promote Healing Improve Circulation Reduce Inflammation.” While the products are labeled to contain
(b)(4)
as active ingredients, which are permitted by M017 to be active ingredients in counterirritant external analgesics, “natural herbs”; however, are not permitted as active ingredients in M017 in combination or as sole ingredients. Although the products’ Drug Facts Panel do not specifically list natural herb ingredients as active ingredients, the claim that the products are formulated with “Natural herbs to Promote Healing Improve Circulation Reduce Inflammation” purports the natural herbs furnish pharmacological activity, demonstrating that natural herbs are “active ingredients” as defined in 21 CFR 201.66(b)(2).
3
Thus, as formulated and labeled, your “Bamboo Pharmacy® Mobility penetrating muscle & joint rub” and “Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub” products do not comply with the applicable conditions specified in M017 and have not otherwise been found GRASE.
4
Accordingly, these products are new drugs within the meaning of section 201(p) of the FD&C Act, 21 U.S.C. 321(p), and there is no basis under section 505G of the FD&C Act under which these products would be legally marketed without an approved application. Because there are no applications in effect for these products, these products are unapproved new drugs.
The introduction or delivery for introduction of these unapproved new drug products into interstate commerce violates sections 505(a) and 301(d) of the FD&C Act, 21 U.S.C. 355(a) and 331(d).
Misbranded Drug Violations
Additionally, “Bamboo Pharmacy® Mobility penetrating muscle & joint rub” and “Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub” are misbranded under section 502(ee) of the FD&C Act, 21 U.S.C. 352(ee), because these products are nonprescription drugs subject to section 505G of the FD&C Act, 21 U.S.C. 355h, but do not comply with the requirements for marketing under that section and are not the subject of an application approved under section 505 of the FD&C Act, 21 U.S.C. 355.
The introduction or delivery for introduction of a misbranded drug into interstate commerce violates section 301(a) of the FD&C Act, 21 U.S.C. 331(a).
Conclusion
The violations cited in this letter are not intended to be an all-inclusive list of violations that exist at your facility. You are responsible for investigating and determining the causes of any violations and for preventing their recurrence or the occurrence of other violations.
FDA placed all drugs and drug products offered for import into the United States from your firm on Import Alert 66-40 on March 24, 2026.
Correct any violations promptly. FDA may withhold approval of new applications or supplements listing your firm as a drug manufacturer until any violations are completely addressed and we confirm your compliance with CGMP. We may re-inspect to verify that you have completed corrective actions to any violations.
Failure to address any violations may also result in the FDA continuing to refuse admission of articles manufactured at Macau-Union Pharmaceutical Limited, at 3-3A Rua Cinco Do Bairro Da Areia Preta, Room B 1/F, Industrial Veng Fong, into the United States under section 801(a)(3) of the FD&C Act, 21 U.S.C. 381(a)(3). Articles under this authority that appear to be adulterated or misbranded may be detained or refused admission, in that the methods and controls used in their manufacture do not appear to conform to CGMP within the meaning of section 501(a)(2)(B) of the FD&C Act, 21 U.S.C. 351(a)(2)(B) and are misbranded under section 502 of the FD&C Act, respectively.
This letter notifies you of our findings and provides you an opportunity to address the above deficiencies. After you receive this letter, respond to this office in writing within 15 working days Specify what you have done to address any violations and to prevent their recurrence. In response to this letter, you may provide additional information for our consideration as we continue to assess your activities and practices. If you cannot complete corrective actions within 15 working days, state your reasons for delay and your schedule for completion.
Send your electronic reply to CDER-OC-OMQ-Communications@fda.hhs.gov. Identify your response with FEI 3011219786 and ATTN: Rory Geyer.
Sincerely,
/S/
Francis Godwin
Director
Office of Manufacturing Quality
Office of Compliance
Center for Drug Evaluation and Research
/S/
Tina Smith
Captain, U.S. Public Health Service
Director
Office of Unapproved Drugs & Labeling Compliance
Office of Compliance
Center for Drug Evaluation and Research
__________________________
1
M017 reflects the conditions in the relevant final order established and in effect under Section 505G of the FD&C Act; see Order ID OTC000033, available at FDA’s website OTC Monographs@FDA, https://www.accessdata.fda.gov/scripts/cder/omuf/index.cfm?event=OrderDetail&orderid=OTC000033.
2
See 21 CFR 201.66(b)(2).
3
Under 21 CFR 201.66(b), an active ingredient is a component of a drug intended to furnish pharmacological activity or other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of disease, or to affect the structure or function of the body.
4
FDA is not aware of any adequate and well-controlled clinical trials in the published literature that support a determination that “Bamboo Pharmacy® Mobility penetrating muscle & joint rub” and “Bamboo Pharmacy® Relief + Recovery deep tissue pain relieving rub” are GRASE for use under the conditions prescribed, recommended, or suggested in their labeling, nor has FDA determined these drug products to be GRASE pursuant to an order issued under section 505G(b).
Content current as of:
06/09/2026
Regulated Product(s)
Drugs