FDA authorizes four emergency animal drugs against New World screwworm

The Food and Drug Administration has announced the issuance of four Emergency Use Authorizations (EUA) for animal drugs against infestations caused by New World screwworm (Cochliomyia hominivorax; NWS) in livestock, pets and wildlife. The notice, filed under docket FDA–2026–N–0004, appears in the Federal Register of Thursday, October 15, 2026 (Vol. 91, No. 198, p. 65562). The document is signed by Grace R. Graham, Deputy Commissioner for Policy, Legislation, and International Affairs.

Section 564 of the Federal Food, Drug, and Cosmetic Act (21 U.S.C. 360bbb–3) allows the FDA to authorize the use of an unapproved animal drug, or an unapproved use of an approved one, when there is no adequate, approved and available alternative. The four authorizations follow the determination made on August 18, 2025 by the Secretary of Health and Human Services (HHS) that a significant potential exists for a public health emergency involving NWS; notice of that determination and declaration was published in the Federal Register on August 20, 2025 (90 FR 40609). The agency had previously announced three EUAs for animal products against the same pest in a notice published on August 31, 2026.

The four authorizations

• Elanco US Inc. — CLiK Extra (dicyclanil topical suspension) wound spray, issued August 7, 2026, for application on or around wounds to prevent NWS myiasis in sheep, cattle, goats, swine and camelids.
• Zoetis Inc. — Simparica TRIO (sarolaner, moxidectin and pyrantel chewable tablets), issued August 13, 2026, for the treatment of NWS myiasis in dogs and puppies.
• Bimeda Animal Health Ltd. — Bimectin (ivermectin) injection, issued August 27, 2026, for the prevention of NWS myiasis in cattle.
• Sergeant’s Pet Care Products LLC — CAPSTAR (nitenpyram) tablets, issued September 3, 2026, for the treatment and prevention of NWS myiasis in dogs, puppies, cats and kittens 2 pounds of body weight or greater and 4 weeks of age and older.

Wildlife species and conditions of use

The Elanco authorization also covers the following captive and captured wildlife species: cervids, American bison, bighorn sheep and Sonoran pronghorn. Each authorization is effective on its date of issuance and contains conditions on the emergency use of the product.

The initial authorizations are reprinted in full in the notice, together with explanations of the reasons for issuance, as required by section 564(h)(1) of the FD&C Act. Any subsequent reissuance of the authorizations will be posted on the agency’s website.

Public comment and access to the texts

Interested persons and organizations may submit written views, recommendations and data to inform the forthcoming public health risk assessment through https://www.regulations.gov; comments are not accepted by email. Requests for single copies of the EUAs should be sent to the Policy and Regulations Staff, Center for Veterinary Medicine, Food and Drug Administration, 5001 Campus Drive, College Park, MD 20740.

The contact for further information is Crystal Groesbeck, Center for Veterinary Medicine (240–402–0819). The full texts of the authorizations are available on the FDA’s New World screwworm information page for veterinarians.

The four authorizations hand cattle, sheep, goat and swine producers, together with companion-animal and wildlife veterinarians, federally backed tools to treat and prevent a parasitic infestation that has disrupted livestock production and cross-border animal trade in North America. Because the products are authorized only under emergency conditions, their use remains subject to the terms of each authorization and to the surveillance attached to the HHS declaration.

Source: Federal Register, Vol. 91, No. 198, 15 October 2026, Notices, p. 65562 (official reference: FR Doc. 2026–21084).