Pharmaceutics. 2019 Jan 14;11(1):29.
Transungual Delivery of Ciclopirox Is Increased 3–4-Fold by Mechanical Fenestration of Human Nail Plate in an In Vitro Model
Onychomycosis is a fungal infection of nails that is widespread and difficult to treat because of the impermeable nature of human nails. Topically applied anti-fungal agents cannot penetrate this structure, and treatment regimens often resort to systemic antifungals with concomitant side effects. One recent clinical study suggested that mechanical fenestration of the nail using an intelligent nail drill might be a possible solution to this problem. In this work, an in vitro model of the transungual delivery of antifungal agents is presented, which utilizes real nail tissue and an inline flow system. This system was deployed to measure transungual delivery of ciclopirox and determined that nail fenestration improved drug delivery by 3–4-fold after 42 days. This study bolsters the argument that nail fenestration should be accepted as a pretreatment for onychomycosis and offers a way of evaluating new drugs or formulations designed to combat this condition.
Rapid Treatment of Subungual Onychomycosis Using Controlled Micro Nail Penetration and Terbinafine Solution.
Onychomycosis continues to be a common and intractable problem in adults, often responding poorly to topical treatment due to limited drug penetration of the nail plate. Improving penetration has been attempted previously by chemical and physical means with some success. The authors present three cases of toenail onychomycosis treated topical terbinafine 1% solution using controlled micro-penetration of the nail using a novel intelligent nail drill system which is able to drill nail plate without penetrating the delicate nail bed beneath. The cases illustrate how the device has been successfully employed to deliver the anti-fungal drug directly and rapidly to the site of infection with minimal side effects or complications, whilst maintaining the nail integrity. J Drugs Dermatol. 2016;15(8):974-978.
J Dermatolog Treat. 2016 Oct;27(5):480-3. doi:10.3109/09546634.2016.1151856. Epub 2016 Mar 31.
An open comparative study of nail drilling as adjunctive treatment for toenail onychomycosis
Introduction Novel treatment regimens are being developed to improve drug penetration through the nail plate. This study investigated the efficacy of nail drilling regimens for the treatment of onychomycosis. Methods Participants were assigned to holes with combination (oral plus topical terbinafine) therapy (Group 1), holes with topical terbinafine (Group 2) or topical terbinafine only (Group 3). Measurement of clear nail and mycology was performed at baseline and at weeks 4, 10, 16, 22 and 28. Mixed linear models were used to compare mean percent clear nail. Mycological cure rates were also tabulated for each group. Tolerability and adverse events were documented. Results Ninety-eight participants were enrolled (106 nails). Both groups with holes had significantly higher percentage of clear nail compared with topical terbinafine alone. Although no significant difference between the two groups where holes were drilled in the nail plate, Group 1 demonstrated improvement over Group 3 earlier than Group 2 (visit 2 versus visit 4). Group 1 also had the highest mycological cure rates. Conclusion Treatment with holes plus topical terbinafine produces significantly greater improvement in toenails' appearance and higher mycological cure rates compared to treating the dorsal aspect of the nail plate with topical terbinafine alone.