Zoetis won FDA approval on Feb. 25 for Simparica (sarolaner), a once-monthly chewable pill that fends off fleas and four types of ticks, setting up a three-way race between Zoetis, Merck Animal Health and Sanofi's Merial to capture a global market for antiparasitics that consultant Vetnosis estimates to be worth more than $4 billion a year.