The FDA issued a warning letter to Chinese API maker Zhejiang Huahai, the company implicated in a global recall of contaminated valsartan, for failing to adequately investigate the root cause of the NDMA contamination at its Linhai, Taizhou Zhejiang facility.
The agency investigated the API manufacturing facility from July 23 to Aug. 3 and found significant CGMP deviations. It noted that the facility — which was placed on an import alert on September 28 — failed to comprehensively investigate the root cause behind its contaminated valsartan API.
After an investigation prompted by a customer complaint, the firm concluded that only one of its manufacturing processes for valsartan involved NDMA. But when the FDA analyzed valsartan samples and finished drug products manufactured with the API, it discovered multiple batches made through a different process that were contaminated with NDMA.