Merck updates Zilmax: FDA approval, plans field-use study
By Lisa M. Keefe on 11/5/2014
The Food and Drug Administration has approved an alternative method of administering Zilmax to cattle in order to ensure the “appropriate dose” of the additive, with an eye on the lower targeted dose of the approved range for daily consumption, according a news release from the manufacturer, Merck Animal Health.
“Research results and industry data showed that cattle weights, and thus feed consumption rates, have been steadily increasing over time. This created the possibility that certain cattle could consume feed quantities that result in ingestion of Zilmax in an amount that exceeds the approved dose,” the release said.
Using it described as “component feeding” cattle feeders "[can] mix Zilmax in feed to deliver a lower targeted dose,” Merck said. With the recommended dose range being from 60 to 90 mg per head per day, the component feeding system is geared toward the lower end of that range.
Meanwhile, the FDA also approved additional label modifications for Zilmax for those feeders who continue to use a “complete feed” system of administering the additive. The labels will include an updated caution statement that notes cattle should not be fed more than 90 mg per head per day of Zilmax.
The “capstone” element of Merck’s promised five-step plan is extensive field-use trials, said David Yates, a nutritionist with the company, in an interview with Meatingplace. The company initially planned to do a scientific audit, but the company’s Zilmax advisory board — the first of the company’s five steps, completed a year ago — recommended the more extensive trials instead, Yates said.
“We are working for industry alignment in order to initiate the in-field use study,” Yates said. “We are working with all parties along the chain, from ranchers to the retailers and foodservice end. When we conduct the study it will be well-known that the study’s going on and the results will be transparent.”
The study will observe the cattle — a control group and one fed Zilmax — for a series of effects at the feedlot, in transportation and at the packing plant. The study will be conducted by a third-party auditor. The challenge has been to line up participation by all the parties involved.
“We are working to get alignment through the industry so that everybody knows what’s going on, that this is the next step, and agree to that,” Yates said. “I wouldn’t even venture a guess” as to when all parties will reach agreement on in-field use trial participation, he said.
I’ts complicated, time-consuming and labor-intensive, but we have ongoing discussion with all parties within the chain. Once we have alignment, we’ll move forward,” Yates added.