FDA WARNING_LETTER - Hong Qiangxing (Shen Zhen) Electronics Limited - August 07, 2025

The FDA issued a Warning Letter to Hong Qiangxing Shenzhen Electronics Limited following an inspection conducted from August 4 to August 7, 2025, in Shenzhen, China. The company manufactures medical devices, including wrist blood pressure monitors and various transcutaneous electric nerve stimulators (TENS) and powered muscle stimulators (PMS). The inspection revealed significant violations of the Quality System Regulation (21 CFR Part 820) under the Federal Food, Drug, and Cosmetic Act, indicating that the firm"s devices are adulterated due to manufacturing control deficiencies.

Key violations primarily involved inadequate design controls. These included repeated failures to establish and maintain procedures for device design, specifically concerning inadequate software validation for their TENS and PMS devices (Model SM9109A), and insufficient documentation and evaluation of design changes. Furthermore, the company failed to maintain adequate procedures for design validation and verification, evidenced by undocumented sample size rationales and the use of samples not produced under defined operating conditions. Design history files also lacked sufficient raw data and manufacturing records for verification and validation samples; these were repeat violations from a July 2016 inspection.

The firm"s responses, dated August 21, September 26, and October 8, 2025, were deemed inadequate by the FDA. While corrective and preventive actions were proposed, these responses failed to address the crucial requirement for a retrospective review of previously manufactured devices and past design changes to ensure their compliance. Hong Qiangxing Shenzhen Electronics Limited must implement comprehensive corrective actions to address these systemic quality system deficiencies.