NEW YORK (AP) — Eli Lilly will sell its heartworm treatment for dogs to garner U.S. approval for its $5.4 billion acquisition of the animal health division belonging to Novartis.

The Federal Trade Commission said Monday that it is requiring the sale of Eli Lilly’s Sentinel heartworm products because the Novartis deal would reduce competition and lead to higher prices. Eli Lilly will sell Sentinel to French pharmaceutical company Virbac.

Eli Lilly first said it would buy the Novartis Animal Health in April. Eli Lilly said it would combine it with its animal health business Elanco to create the second-largest animal health company in the U.S.

The European Union already approved the acquisition in October.

Shares of Eli Lilly and Co., based in Indianapolis, fell $1.11, or 1.5 percent, to $71.29 in afternoon trading.