Elanco Animal Health Incorporated (NYSE: ELAN) announced the phased launch of Befrena (tirnovetmab), an anti-IL-31 monoclonal antibody injection for treating canine allergic and atopic dermatitis. The company received approval from the U.S. Department of Agriculture in December 2025.

Befrena provides 6 to 8 weeks of itch relief compared to the 4 to 8 weeks offered by the current market treatment, lokivetmab. The injection begins controlling itch within 24 hours and is administered in veterinary clinics. The treatment has no age or weight restrictions for dogs.

Select veterinarians are currently using Befrena through an Early Experience Program. The company cited the $1.3 billion U.S. canine dermatology market in its announcement.

"The commercial launch of Befrena into the $1.3 billion U.S. canine dermatology market is another exciting milestone in our innovation journey," said Bobby Modi, Executive Vice President, U.S. Pet Health and Global Digital Transformation.

Befrena represents Elanco's second monoclonal antibody product in the U.S. pet health market, joining Trutect, which treats canine parvovirus. The company also markets Zenrelia (ilunocitinib tablets) for dermatology treatment, approved within the past two years.

According to Elanco's data, nearly 9 in 10 dogs in the U.S. experience itch symptoms at some point during the year. The treatment works by neutralizing IL-31, a cytokine involved in transmitting itch signals to the brain.

Veterinarians participating in the Early Experience Program reported positive outcomes. Dr. Matt Lane at Liberty Animal Hospital noted that one treated dog stopped itching within 24 hours and showed hair regrowth after three weeks.