WARNING LETTER
Xiamen Kang Zhongyuan Biotechnology Co., Ltd.
MARCS-CMS 719320 —
March 23, 2026
Delivery Method:
VIA EMAIL WITH READ RECEIPT
Product:
Drugs
Recipient:
Recipient Name
Mr. Haisen Yang
Recipient Title
General Manager
Xiamen Kang Zhongyuan Biotechnology Co., Ltd.
No. 2018-2, Jietou Road
Xiang'an Qu
Xiamen Shi
Fujian Sheng
,
361101
China
Issuing Office:
Center for Drug Evaluation and Research (CDER)
United States
Warning Letter
320-26-56
March 23, 2026
Dear Mr. Yang:
The United States Food and Drug Administration (FDA) inspected your drug manufacturing facility, Xiamen Kang Zhongyuan Biotechnology Co., Ltd., FEI 3027976266, at No. 2018-2, Jietou Road, Xiang’an District, Xiamen, Fujian 361101, China, from August 12 to 15, 2025.
Because your drug products were prepared, packed, or held under insanitary conditions, whereby they may have become contaminated with filth or rendered injurious to health, your drug products are adulterated within the meaning of section 501(a)(2)(A) of the Federal Food, Drug, and Cosmetic Act (the FD&C Act), 21 U.S.C. 351(a)(2)(A).
We reviewed your September 8, 2025, response to our Form FDA 483 in detail and acknowledge receipt of your subsequent correspondence.
During our inspection, our investigators observed specific violations including, but not limited to, the following:
Insanitary Conditions
You do not have adequate controls in place to maintain a suitable production environment and to prevent contamination of drug products manufactured at your facility. During the inspection, FDA investigators observed areas of your facility to be in a state of disrepair, poorly cleaned, and poorly maintained, as evidenced by:
Grime and discolored lubricant observed on manufacturing equipment, including a
(b)(4)
machine used to
(b)(4)
drug products. Your firm stated that some portion of drug products is routinely discarded due to lubricant contamination during the use of this equipment.
Standing water observed on the floor of the manufacturing area, and standing water inside equipment marked as clean.
A visibly dirty tube attached to a
(b)(4)
in your manufacturing area, used to transfer
(b)(4)
, which is a component in your manufacturing.
Unknown liquid droplets on surfaces directly above manufacturing equipment.
Flies in the manufacturing area.
A live cockroach in the secondary packaging area.
Apparent mold on the air-conditioning vents in the storage area for bulk drug products and components.
In your response, you provided information regarding the corrective actions you completed, or plan to complete, to address the observations noted during the inspection. For example, you stated that you performed an immediate cleaning of the
(b)(4)
machine, and that you plan to implement a cleaning and validation plan.
Your response is inadequate because you failed to conduct a retrospective review and assessment of the risks to product quality, including all potential contamination risks.
In response to this letter, provide the following:
Your corrective action and preventive action plan to implement routine, vigilant operations management oversight of facilities and equipment. This plan should ensure, among other things, prompt detection and effective remediation of equipment/facilities issues, adherence to appropriate preventive maintenance schedules, and improved systems for ongoing management review.
Detailed procedures demonstrating that your firm can maintain buildings free from pests and that your buildings can remain clean and sanitary.
Documentation that supports your corrective actions, such as work orders, room qualification, photos of any repairs your firm has made to correct the violation, and systemic plans to ensure that the manufacturing areas remain adequately designed, controlled, and maintained.
Access to information during inspection, and delaying, denying, and limiting the inspection
During the inspection, your firm also made misleading or deceptive statements and may have delayed the investigators’ access to accurate and truthful information. For example:
Your Chief Quality Officer admitted to providing false documents related to the testing of your finished drug product.
Your firm provided false manufacturing records related to ingredient quality testing. Our investigators requested a copy of a logbook on August 13, 2025, that appeared to contain missing data (i.e., the logbook had blank spaces where entries should have been recorded). After repeated inquiries, you provided the manufacturing logbook to our investigators on August 15, 2025, with information recorded that had not been present on August 13, 2025, the date of our original request. Your firm later acknowledged that the associated laboratory records were “missing.”
When an owner, operator, or agent delays, denies, limits, or refuses an inspection, the drugs may be deemed adulterated under section 501(j) of the FD&C Act. See FDA’s guidance document Circumstances that Constitute Delaying, Denying, Limiting, or Refusing a Drug or Device Inspection at https://www.fda.gov/media/86328/download. See also FDA’s guidance document Data Integrity and Compliance With Drug CGMP for guidance on establishing and following CGMP compliant data integrity practices at https://www.fda.gov/media/119267/download.
In your response, you committed to ensuring that proper testing and recordkeeping protocols are in place before the release of batches. Your response is inadequate because you did not conduct a comprehensive evaluation of other records in which data may have been misrepresented or manipulated by your employees.
We strongly recommend that you retain a qualified consultant to assist in your remediation. In response to this letter, provide:
A comprehensive investigation into the extent of the inaccuracies in data records and reporting, including results of the data review for drugs distributed to the United States. Include a detailed description of the scope and root causes of your data integrity lapses.
A current risk assessment of the potential effects of the observed failures on the quality of your drugs. Your assessment should include analyses of the risks to patients caused by the release of drugs affected by a lapse of data integrity, and analyses of the risks posed by ongoing operations.
A management strategy for your firm that includes the details of your global corrective action and preventive action plan. The detailed corrective action plan should describe how you intend to ensure the reliability and completeness of all data generated by your firm, including microbiological and analytical data, manufacturing records, and all data submitted to FDA.
Drug Recall
On March 4, 2026, FDA held a teleconference with you recommending you consider removing batches of mentholated cough drops currently in distribution from the U.S. market. You agreed to initiate a recall of certain lots after the discussion.
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 20, 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. 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 refusing admission of articles manufactured at Xiamen Kang Zhongyuan Biotechnology Co., Ltd., into the United States under section 801 of the FD&C Act, 21 U.S.C. 381. Articles under this authority that appear to be adulterated or misbranded are subject to detention or refusal of admission.
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 3027976266 and ATTN: Maria Pavco.
Sincerely,
/S/
Francis Godwin
Director
Office of Manufacturing Quality
Office of Compliance
Center for Drug Evaluation and Research
Content current as of:
04/21/2026
Regulated Product(s)
Drugs