Existing Product Receives Conditional Approval for New World Screwworm
Dectomax-CA1 Injectable receives conditional FDA approval for prevention and treatment of New World screwworm in U.S. cattle.
October 2, 2025
Zoetis Inc. announced Tuesday, Sept. 30, that Dectomax®-CA1 Injectable is the first and only parasite control product to receive conditional approval from the U.S. Food and Drug Administration for the prevention and treatment of infestations caused by the larvae of Cochliomyia hominivorax (myiasis), and prevention of reinfestation for 21 days. This conditional approval applies to beef cattle, female dairy cattle less than 20 months of age, pregnant beef cows, newborn calves and bulls.
In a news release announcing the approval, Zoetis stated it is committed to supporting livestock producers with scientific solutions for this economically devastating pest. New World screwworm (NWS) poses a continuing threat to livestock health, and the financial ramifications of the disease to the U.S. ag economy are estimated in the billions of dollars.1
“New World screwworm has the potential to bring unprecedented economic and animal health harm to livestock producers,” said Mike Lormore, director of cattle and pork technical services at Zoetis. “Our top priority is to support keeping animals healthy and provide timely, efficacious solutions to our customers and partners. With this conditional approval, Dectomax-CA1 Injectable can now be used as part of safe, effective control measures against New World screwworm.”
Zoetis has long supported a One Health approach to emerging and transboundary infectious diseases and has a strong track record of quickly developing innovative solutions to provide customers with the right mix of tools for prevention and treatment strategies.
Livestock producers are encouraged to work closely with their herd veterinarian to implement strategic prevention and control measures.
Early detection of NWS and rapid response are critical to protecting the health of animals and the livestock industry. Producers are encouraged to immediately report any suspicious wounds, maggots or infestations to their local accredited veterinarian, state animal health official or USDA’s Animal and Plant Health Inspection Service (APHIS). USDA APHIS animal health contacts can be found online here.
In the first half of 2026, producers and veterinarians will begin to see the 250-mL and 500-mL bottles of Dectomax Injectable with a new label for Dectomax-CA1 (doramectin injection). Dectomax-CA1 is the same effective doramectin formulation as Dectomax Injectable.
For more information on New World screwworm and the conditional approval for Dectomax-CA1 Injectable, visit zoetisus.com/NewWorldscrewworm.
Dectomax-CA1 is conditionally approved by FDA pending a full demonstration of effectiveness under NADA 141-616.
Dectomax and Dectomax-CA1 Injectable for use in cattle have a 35-day preslaughter withdrawal period. Do not use in female dairy cattle 20 months of age or older. Do not use in calves to be processed for veal. Dectomax Injectable for use in swine has a 24-day preslaughter withdrawal period. Use of Dectomax or Dectomax-CA1 in dogs may result in fatalities. Consult your veterinarian for assistance in the diagnosis, treatment and control of parasitism.
Editor’s note: Adapted from a news release provided by Zoetis Inc. [Lead photo by Leann Schleicher.]
1APHIS. https://www.aphis.usda.gov/sites/default/files/nws-historical-economic-impact.pdf. Accessed 8/15/25.
Angus Beef Bulletin EXTRA, Vol. 17, No. 10-A
Topics: Equipment / Facilities , Health , Industry News , News
Publication: Angus Beef Bulletin
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