Tavaborole, sold under the brand name Kerydin, is a
topical
A topical medication is a medication that is applied to a particular place on or in the body. Most often topical medication means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes ...
antifungal medication
An antifungal medication, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis (thrush), serious systemic infections such as cryp ...
for the treatment of
onychomycosis
Onychomycosis, also known as tinea unguium, is a fungal infection of the nail. Symptoms may include white or yellow nail discoloration, thickening of the nail, and separation of the nail from the nail bed. Toenails or fingernails may be affected, ...
, a
fungal infection of the
nail
Nail or Nails may refer to:
In biology
* Nail (anatomy), toughened protective protein-keratin (known as alpha-keratin, also found in hair) at the end of an animal digit, such as fingernail
* Nail (beak), a plate of hard horny tissue at the tip ...
and
nail bed with a complete clearance rate of 6-7% and partial clearance rate of 23-24% in individuals whose “infection border does not reach the cuticle at the base of the large toenail.”
Tavaborole was approved by the US FDA in July 2014. The medication inhibits an essential fungal
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...
,
leucyl-tRNA synthetase
Leucyl-tRNA synthetase, cytoplasmic is an enzyme that in humans is encoded by the ''LARS'' gene.
Function
This gene encodes a cytosolic leucine-tRNA synthetase, a member of the class I aminoacyl-tRNA synthetase family. The encoded enzyme catal ...
, that is required for
protein synthesis. The inhibition of protein synthesis leads to termination of
cell growth and then
cell death
Cell death is the event of a biological cell ceasing to carry out its functions. This may be the result of the natural process of old cells dying and being replaced by new ones, as in programmed cell death, or may result from factors such as d ...
, eliminating the fungal infection.
Medical uses
Tavaborole is used in the treatment of
onychomycosis
Onychomycosis, also known as tinea unguium, is a fungal infection of the nail. Symptoms may include white or yellow nail discoloration, thickening of the nail, and separation of the nail from the nail bed. Toenails or fingernails may be affected, ...
. In clinical trials, tavaborole was more effective than the vehicle (ethyl acetate and propylene glycol) alone in curing onychomycosis. In two studies, fungal infection was eliminated using tavaborole in 6.5% of the cases vs. 0.5% using the vehicle alone, and 27.5% vs. 14.6% using the vehicle alone.
Side effects
Application site exfoliation, erythema (rash), and irritation are possible side effects, and may occur in less than 5% of individuals.
Pharmacology
Tavaborole acts as an inhibitor of fungal
leucyl-tRNA synthetase
Leucyl-tRNA synthetase, cytoplasmic is an enzyme that in humans is encoded by the ''LARS'' gene.
Function
This gene encodes a cytosolic leucine-tRNA synthetase, a member of the class I aminoacyl-tRNA synthetase family. The encoded enzyme catal ...
.
Pharmacokinetics
Tavaborole, when prepared with a 1:1 mixture of ethyl acetate and propylene glycol, has the ability to fully penetrate through the human nail. In studies with cadaver fingernails, a 5% solution of tavaborole penetrated the nail an average of 524.7 mcg/cm
2 after two weeks of daily use.
Tavaborole is detectable in the blood at a level of 3.54 ng/mL after a single use of 0.2 mL of the 5% solution. Tavaborole has an
elimination half-life
Biological half-life (also known as elimination half-life, pharmacologic half-life) is the time taken for concentration of a biological substance (such as a medication) to decrease from its maximum concentration ( Cmax) to half of Cmax in the bl ...
of 28.5 hours, a maximum concentration of 5.17 ng/mL after two weeks of daily use, and takes 8 days to reach the maximum concentration.
Society and culture
Economics
Tavaborole began
phase III clinical trial
Clinical trials are prospective biomedical or behavioral research studies on human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel vaccines, drugs, diet ...
s in December 2010 and was approved by the US FDA in July 2014.
Originally developed by
Anacor
Pfizer Inc. ( ) is an American multinational pharmaceutical and biotechnology corporation headquartered on 42nd Street in Manhattan, New York City. The company was established in 1849 in New York by two German entrepreneurs, Charles Pfizer ...
, it is now marketed in the United States by
Novartis
Novartis AG is a Swiss-American multinational pharmaceutical corporation based in Basel, Switzerland and
Cambridge, Massachusetts, United States (global research).name="novartis.com">https://www.novartis.com/research-development/research-loc ...
subsidiary
Sandoz
Novartis AG is a Swiss-American multinational pharmaceutical corporation based in Basel, Switzerland and
Cambridge, Massachusetts, United States (global research).name="novartis.com">https://www.novartis.com/research-development/research-loca ...
. Anacor was paid and also entered into a
profit sharing scheme for future sales. A 10 mL bottle of a 5% solution of tavaborole will cost the patient without insurance about $1,356.
See also
*
Crisaborole – a structurally related topical medication used for the treatment of mild-to-moderate
atopic dermatitis (eczema)
References
External links
*
{{Portal bar , Medicine
American inventions
Antifungals
Fluoroarenes
Organoboron compounds
Pfizer brands