--Zimmer says FDA inspection of Puerto Rico plant turned up concerns about manufacturing of certain implants

--FDA in letter noted manufacturing, testing issues related to Trilogy Acetabuar System products, company says

--Zimmer says it is notifying customers of manufacturing issue, but hasn't withdrawn any products

(Adds context on metallic spikes in fourth paragraph and a no comment from Zimmer in seventh paragraph.)

 
   By Kristin Jones 
 

Zimmer Holdings Inc. (ZMH) said a U.S. Food and Drug Administration inspection of its plant in Puerto Rico turned up concerns about the manufacturing of certain hip implants.

The orthopedic maker's Zimmer Inc. subsidiary received a warning letter from the FDA dated Sept. 19, the company said in a regulatory filing Monday. In the letter, the FDA noted manufacturing and testing issues related to the company's Trilogy Acetabular System products, which are implanted in hip-replacement surgery.

Specifically, the U.S. drug regulator noted that Zimmer hadn't implemented a testing mechanism to show that its products met design specifications. The company also hadn't validated the effect of certain manufacturing operations on Trilogy products that incorporate metallic spikes.

Spikes are used to connect the hip replacement cup to a patient's bone when cement and screws are deemed insufficient.

The FDA requires that drug and medical-device makers undertake steps to ensure the quality of the design and manufacture of its products, known as process validation.

Zimmer said it is notifying customers of the manufacturing issue, but that it hasn't withdrawn any products. The company also said it previously suspended release of the spiked products, pending validation of the processes cited in the letter, and expects to complete validation in the next few weeks.

A Zimmer spokesman declined to comment further.

Shares gained 11 cents to $67.98 in after-hours trading. Through Monday's close, the stock was up 27% so far this year.

--Joseph Walker contributed to this article.

Write to Kristin Jones at kristin.jones@dowjones.com

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