Elanco Animal Health's Zenrelia (ilunocitinib) has received FDA approval for controlling pruritus linked to allergic dermatitis and atopic dermatitis in dogs aged 12 months and older. This once-daily oral Janus kinase (JAK) inhibitor provides a new option for veterinarians and pet owners managing canine dermatological conditions.
Efficacy and Safety Data
A randomized, double-blind, head-to-head noninferiority study involving 338 dogs with confirmed atopic dermatitis across multiple sites in four countries compared Zenrelia to a market-leading JAK inhibitor. Results indicated that Zenrelia was at least as effective as the comparator at the primary endpoint on Day 28. Promising additional endpoints included:
- Greater relief from itch and skin lesions over time with consistent once-daily dosing.
- 77% of Zenrelia-treated dogs achieved clinical remission of itch, compared to 53% in the comparator group (P≤0.05).
- Veterinarians and owners rated Zenrelia higher for overall treatment response from Day 28 through Day 112 (P≤0.05).
- The adverse event profiles were similar between the two groups.
Pricing and Convenience
Elanco has announced that Zenrelia will be priced approximately 20% lower than the current market-leading JAK inhibitor, potentially offering a more affordable option for pet owners. Bobby Modi, Executive Vice President, U.S. Pet Health and Global Digital Transformation, highlighted the convenience of Zenrelia's once-daily dosing, which may also minimize the risk of rebound itch compared to the market incumbent.
Safety Considerations
The Zenrelia label includes a boxed warning concerning vaccine administration. Based on a vaccine response study, dogs receiving Zenrelia may be at risk of vaccine-induced disease and inadequate immune response to vaccines. The recommendation is to discontinue Zenrelia for at least 28 days to 3 months prior to vaccination and withhold it for at least 28 days after vaccination. Veterinarians are advised to review the complete package insert before prescribing Zenrelia.
Dr. Mara Tugel, veterinarian and Dermatology Medical Strategic Lead at Elanco, stated, "Zenrelia has been demonstrated to be safe and highly effective in a number of studies. We recognize that veterinarians need clinically relevant data to guide treatment choices, and plan to pursue additional studies to evaluate vaccine response in Zenrelia-treated dogs. We will continue to work to improve the label over time."
