* Company says production continues
* Third safety-related warning this year
FRANKFURT, Aug 23 (Reuters) - U.S. regulators have issued a third warning this year for German healthcare group Fresenius to improve procedures at its sites, this time a blood bag manufacturing plant in Puerto Rico.
A letter to the company from the U.S. Food and Drug Administration (FDA) took issue with complaint-handling procedures and labelling at the Puerto Rico site, the German company said on Friday, adding that patients had not been put at risk.
Fresenius said that it is addressing the concerns raised by the FDA and that production at the plant is continuing, adding that full-year earnings targets for the infusion drugs and blood transfusion unit Kabi are not at risk.
Only last month Fresenius received an FDA warning letter related to an inspection of its cancer drug plant in Kalyani, India.
In March the company's separately listed subsidiary Fresenius Medical Care, the world's largest dialysis company, was told by U.S. regulators to improve the way it sterilises certain dialyzers for filtering patients' blood.
In May and June Fresenius Kabi voluntarily recalled some magnesium sulphate and benztropine mesylate injections in the United States because of the potential presence of glass particles in the vials.