Safety and tolerability of cinnamaldehyde in orabase for oral candidiasis treatment: phase I clinical trial

Objective: To advance studies on the effect of a new pharmaceutical formulation for the treatment of oral fungal infections, we evaluated the safety and tolerability of orabase ointment containing cinnamaldehyde for use on the oral mucosa.

Material and methods: A clinical trial (phase I) was carried out on 35 individuals with healthy oral mucosa divided into three groups: ointments at 200 µg/mL, n = 12; 300 µg/mL, n = 11; and 400 µg/mL, n = 12. Product safety was assessed using three parameters: (a) clinical evolution as recorded by trained examiners; (b) evolution of the inflammatory process as registered by an exfoliative cytology exam and analyzed by trained pathologists; (c) mucosal swab to count Candida spp. colony-forming units (CFU). These parameters were analyzed both beforehand and at 15 days of treatment.

Results: The three ointment concentrations evaluated did not trigger inflammatory processes. The mycological analyses revealed a reduction of at least 99% in the number of Candida spp. CFU. In the exfoliative cytology analyses, the cells were found to be healthy. Participants reported a pleasant taste, yet 17% reported a slight burning sensation when applying the product.

Conclusions: The ointment is safe and tolerable for use on healthy oral mucosa.

Trial registration: Registration number: RBR-7zwzs3.

Clinical relevance: The ointment proved to be safe and tolerable for use on oral mucosa, encouraging studies to evaluate its clinical efficacy in patients with oral candidiasis, and contributing to a new therapeutic proposal for the treatment of fungal infections caused by Candida spp.