Study compares Easotic and Claro in canine otitis externa
Bottom line
A comparative clinical study is adding evidence to a familiar otitis externa conversation in practice: how quickly dogs improve, and how easy treatment is for teams and pet parents. In a randomized, masked, multicenter field trial published in Frontiers in Veterinary Science in 2026, 86 client-owned dogs with acute otitis externa were evaluated after treatment with either Easotic (Virbac) or Claro (Elanco), each used according to label directions. By Day 28, both products showed high efficacy, but Easotic was associated with faster early improvement in discharge, odor, dirtiness, and stenosis by Day 2, and a higher proportion of veterinarian-rated “Excellent” responses at Days 7 and 28. (frontiersin.org)
Why it matters: For veterinary professionals, the study speaks to two practical issues: speed of visible improvement and treatment fit for the individual case. Otitis externa is a common, painful condition in dogs, and early relief can improve patient comfort, strengthen pet parent confidence, and support adherence to follow-up plans. At the same time, product selection still has to be grounded in otoscopic exam, cytology, tympanic membrane status, and the underlying driver, especially because recurrent otitis is often tied to allergic skin disease or other primary causes. Claro’s label also carries updated safety language around eye exposure, tympanic membrane integrity, and post-approval reports including vestibular signs and deafness, reinforcing the need for careful case selection and administration counseling. (merckvetmanual.com)
What to watch: Watch for whether this head-to-head dataset changes prescribing patterns, follow-up protocols, or manufacturer messaging around fast relief versus single-dose convenience. (frontiersin.org)
Key facts
- Study type
- Randomized, masked, multicenter field trial
- Publication
- Frontiers in Veterinary Science, 2026
- Sample size
- 86 client-owned dogs
- Condition
- Acute otitis externa
- Products compared
- Easotic (Virbac) and Claro (Elanco)
- Treatment schedule
- Easotic once daily for 5 days; Claro single dose
- Key finding
- Both products had high Day 28 efficacy, but Easotic improved discharge, odor, dirtiness, and stenosis faster by Day 2
- Day 28 result
- 85% with Easotic and 79% with Claro reached OTIS3 score of 3 or less in the intention-to-treat analysis
- Safety note
- Claro labeling includes eye protection, intact tympanic membrane, and reports of vestibular signs and deafness
A new head-to-head study is giving veterinary teams fresh comparative data on two established canine otitis externa treatments. In a 2026 Frontiers in Veterinary Science field trial, investigators compared Easotic, a five-day otic suspension from Virbac, with Claro, Elanco’s single-dose otic solution, in 86 client-owned dogs with acute otitis externa. Both treatments performed well by Day 28, but Easotic showed faster improvement in several clinical signs and earned more veterinarian-rated “Excellent” responses at follow-up. (frontiersin.org)
The study builds on a topic that matters in everyday practice because otitis externa is both common and often painful. Published epidemiology and review sources describe it as one of the most frequent canine conditions seen in primary care, with prevalence estimates in general practice commonly landing in the single digits and, in some reports, higher over a dog’s lifetime. Chronic or recurrent disease is especially challenging, because infection is often only part of the picture; allergies, conformational factors, foreign bodies, endocrinopathies, and other primary drivers can keep cases cycling back. (pmc.ncbi.nlm.nih.gov)
In the new trial, dogs with acute otitis externa and an OTIS3 score of at least 5 were assessed at 4 hours and again on Days 2, 7, and 28. Easotic was given once daily for five days, while Claro was administered as a single dose, following label instructions. According to the published abstract, Day 28 efficacy was high for both groups, with 85% of dogs in the intention-to-treat analysis reaching an OTIS3 score of 3 or less with Easotic, versus 79% with Claro, a difference that was not statistically significant. Where the products separated was earlier in the course of treatment: Easotic showed greater reductions from Day 2 in discharge, odor, dirtiness, and stenosis, and higher veterinarian-rated “Excellent” responses at both Day 7 and Day 28. (frontiersin.org)
The dvm360 item appears to draw from the same comparison dataset that Virbac has promoted in product materials and conference presentations tied to the 2024 World Congress of Veterinary Dermatology. Virbac’s product page says 41 dogs received Easotic and 39 received Claro, with evaluations on Days 2, 7, and 28, and cites both an abstract and poster presentation from the Boston meeting. That helps explain why the marketing language emphasizes “fast relief,” while the peer-reviewed publication adds more useful context on study design, endpoints, and comparative outcomes. (vet-us.virbac.com)
There’s also an important safety and workflow backdrop here. Claro remains a familiar convenience option because it is single-dose and clinic-administered, but FDA labeling changes issued in 2021 emphasized eye protection during administration, restraint to reduce post-application head shaking and splatter, confirmation that the tympanic membrane is intact, and post-approval reports that included ataxia, vestibular signs, deafness, keratoconjunctivitis sicca, and tympanic membrane rupture. The same active combination is also used in the generic Simplera, approved by FDA in 2022, underscoring that this formulation class remains relevant in practice. (fda.gov)
Why it matters: For veterinary professionals, this isn’t just a product-comparison story. It’s a reminder that speed of relief, ease of administration, safety profile, and case selection all shape outcomes. Early visible improvement can matter a lot in painful ear cases, especially when pet parents are worried and dogs resist handling. But the broader otitis literature still points to the same fundamentals: cytology is central, ear cleaning may be important depending on the product and case, and long-term success depends on identifying the underlying cause rather than just suppressing secondary infection and inflammation. In other words, a fast-acting product may improve the first week, but it won’t solve recurrent disease on its own. (todaysveterinarypractice.com)
The study did not appear, in the sources reviewed, to generate substantial independent expert commentary beyond manufacturer promotion and publication of the abstract itself. That means the most defensible takeaway is a narrow one: this trial supports Easotic as an effective option with faster early improvement on some signs than Claro, while also confirming that both products achieved strong Day 28 results in acute cases. That’s useful, but it doesn’t replace individualized treatment decisions based on cytology, canal anatomy, membrane integrity, patient temperament, pet parent capacity for at-home administration, and the likelihood of recurrence. (frontiersin.org)
What to watch: The next thing to watch is whether this newly published comparison influences dermatology and general practice prescribing habits, especially in cases where rapid symptom relief is prioritized, or whether convenience and in-clinic administration continue to keep single-dose options competitive despite the added safety counseling they require. (frontiersin.org)