Klox Biophotonic System for management of chronic otitis externa: a randomized controlled clinical trial in dogs

The aim of the study was to evaluate the efficacy of topical KLOX BioPhotonic System (KBS) in the treatment of canine chronic otitis externa versus standard of care therapy. Dogs with spontaneous, chronic otitis externa were randomly divided in three groups: groups QW and BW received KBS once-a-week and twice-a-week, respectively; group C received enrofloxacin and silver sulfadiazine twice-a-day. KBS therapy consists of a topical application of a Biophotonic gel followed with illumination using a handheld LED lamp for 1.5 minutes. The evaluation protocol (T0 to T5; twice-weekly for BW/C, once-weekly for QW) consisted of: clinical assessment (OTIS-3-index-scoring-system; pruritus-severity-scale; pain-severity-score; aural temperature), cytological scoring system, quali-quantitative bacteriologic assessment. All groups (QW, n=21; BW, n=23; C, n=20) showed improvement during the study (QW: P<0.02 for cytological and pain scores, P<10-4 for pruritus, total OTIS-3, temperature and bacteriologic assessments; BW: P<10-4 for all clinical, cytological and bacteriologic assessments; C: P<0.02 for all clinical and cytological assessments, P<10-4 for bacteriologic assessment). BW showed the highest clinical score reduction (P<0.014 in T3; P<0.001 in T4 and T5). BW reached the OTIS-3 cut-off mean score for clinical success at T3, QW reached it at T4, C did not reach it. BW (-92.39±18.91) showed a higher, but not significant (P=0.367), mean-%-reduction of CFU/mL (T0-T5), in comparison to QW (-68.10±93.26) and C (-83.29±27.41). KBS may be considered an innovative therapy in canine chronic otitis externa. KBS twice-a-week recorded the best performance, and the lower frequency of application of KBS compared to standard treatment could increase therapeutic compliance.