Recent research works suggest itraconazole (ITZ) could also be used in the treatment of cancer by inhibiting the
hedgehog pathway[10] in a similar way to
sonidegib.
Medical uses
Itraconazole has a broader spectrum of activity than
fluconazole (but not as broad as
voriconazole or
posaconazole). In particular, it is active against Aspergillus, which fluconazole is not. It is also licensed for use in
blastomycosis,
sporotrichosis,
histoplasmosis, and
onychomycosis. Itraconazole is over 99% protein-bound and has virtually no penetration into
cerebrospinal fluid. Therefore, it should not be used to treat
meningitis or other
central nervous system infections.[11] According to the Johns Hopkins Abx Guide, it has "negligible CSF penetration, however treatment has been successful for cryptococcal and coccidioidal meningitis".[12]
Itraconazole has been explored as an anticancer agent for patients with
basal cell carcinoma,
non-small cell lung cancer, and
prostate cancer.[13] For example, in a phase II study involving men with advanced prostate cancer, high-dose itraconazole (600 mg/day) was associated with significant PSA responses and a delay in tumor progression. Itraconazole also showed activity in a phase II trial in men with non-small cell lung cancer when it was combined with the chemotherapy agent, pemetrexed.[14][15][16] A recent review also highlights its use topically and orally in conjunction with other chemotherapeutic agents for advanced and metastatic basal cell carcinomas that cannot be treated surgically.[17]
Available forms
Itraconazole is produced as blue 22 mm (0.87 in) capsules with tiny 1.5 mm (0.059 in) blue pellets inside. Each capsule contains 100 mg and is usually taken twice a day at twelve-hour intervals. The Sporanox brand of itraconazole has been developed and marketed by
Janssen Pharmaceutica, a subsidiary of
Johnson & Johnson.[citation needed] The three-layer structure of these blue capsules is complex because itraconazole is insoluble and is sensitive to pH. The complicated procedure not only requires a specialized machine to create it, but also the method used has manufacturing problems. Also, the pill is quite large, making it difficult for many patients to swallow. Parts of the processes of creating Sporanox were discovered by the Korean Patent Laid-open No. 10-2001-2590.[18] The tiny blue pellets contained in the capsule are manufactured in
Beerse, Belgium.[18][19]
The oral solution is better absorbed. The
cyclodextrin contained in the oral solution can cause an
osmotic diarrhea, and if this is a problem, then half the dose can be given as oral solution and half as capsule to reduce the amount of cyclodextrin given.[citation needed] "Sporanox" itraconazole capsules should always be taken with food, as this improves absorption, however the manufacturers of "Lozanoc" assert that it may be taken "without regard to meals".[20] Itraconazole oral solution should be taken an hour before food, or two hours after food (and likewise if a combination of capsules and oral solution are used). Itraconazole may be taken with orange juice or
cola, as absorption is also improved by acid. Absorption of itraconazole is impaired when taken with an antacid,
H2 blocker or
proton pump inhibitor.[citation needed]
Side effects
Itraconazole is a relatively well-tolerated drug (although not as well tolerated as
fluconazole or
voriconazole) and the range of adverse effects it produces is similar to the other azole antifungals:[21]
The mechanism of action of itraconazole is the same as the other
azole antifungals: it inhibits the fungal-mediated synthesis of
ergosterol, via inhibition of
lanosterol 14α-demethylase. Because of its ability to inhibit
cytochrome P450 3A4 CC-3, caution should be used when considering interactions with other medications.[24]
Itraconazole is pharmacologically distinct from other
azole antifungal agents in that it is the only inhibitor in this class that has been shown to inhibit both the
hedgehog signaling pathway[25][26] and
angiogenesis.[27][28] These distinct activities are unrelated to inhibition of the
cytochrome P450lanosterol 14 alpha-demethylase and the exact molecular targets responsible remain unidentified. Functionally, the antiangiogenic activity of itraconazole has been shown to be linked to inhibition of glycosylation,
VEGFR2 phosphorylation,[28] trafficking,[29] and cholesterol biosynthesis pathways.[27] Evidence suggests the structural determinants for inhibition of hedgehog signaling by itraconazole are recognizably different from those associated with antiangiogenic activity.[30]
Pharmacokinetics
Itraconazole, like
cyclosporine,
quinidine, and
clarithromycin, can inhibit
P-glycoprotein, causing
drug interactions by reducing elimination and increasing absorption of organic cation drugs. With conventional itraconazole preparations serum levels can vary greatly between patients, often resulting in serum concentrations lower than the therapeutic index.[31] It has therefore been conventionally advised that patients take itraconazole after a fatty meal rather than prior to eating.[32][33]
A product (Lozanoc) licensed through the European union decentralised procedure[34] has increased
bioavailability, decreased sensitivity to co ingestion of food, and hence decreased variability of serum levels.
Chemistry
The itraconazole molecule has three
chiral carbons. The two chiral centers in the dioxolane ring are fixed in relation to one another, and the triazolomethylene and aryloxymethylene dioxolane-ring substituents are always
cis to each other. The clinical formulation is a 1:1:1:1 mixture of four stereoisomers (two enantiomeric pairs).[35][36]
History
Itraconazole was approved for medical use in the United States in 1992.[37]
^Isoherranen N, Kunze KL, Allen KE, Nelson WL, Thummel KE (October 2004). "Role of itraconazole metabolites in CYP3A4 inhibition". Drug Metabolism and Disposition. 32 (10): 1121–1131.
doi:
10.1124/dmd.104.000315.
PMID15242978.
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^World Health Organization (2019). World Health Organization model list of essential medicines: 21st list 2019. Geneva: World Health Organization.
hdl:10665/325771. WHO/MVP/EMP/IAU/2019.06. License: CC BY-NC-SA 3.0 IGO.
^Ip KH, McKerrow K (2021). "Itraconazole in the treatment of basal cell carcinoma: A case-based review of the literature". Australasian Journal of Dermatology. 62 (3): 394–397.
doi:
10.1111/ajd.13655.
PMID34160824.
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^
abUS 20050226924, Lee KH, Park ES, Chi SC, "Composition comprising Itraconazole for oral administration", published 13 October 2005, assigned to FDL Inc.
^
abChong CR, Xu J, Lu J, Bhat S, Sullivan DJ, Liu JO (2007). "Inhibition of Angiogenesis by the Antifungal Drug Itraconazole". ACS Chemical Biology. 2 (4): 263–70.
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^Fraga Fuentes MD, García Díaz B, de Juana Velasco P, Bermejo Vicedo MT (1997). "[Influence of foods on the absorption of antimicrobial agents]". Nutr Hosp (in Spanish). 12 (6): 277–88.
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^Kunze KL, Nelson WL, Kharasch ED, Thummel KE, Isoherranen N (April 2006). "Stereochemical aspects of itraconazole metabolism in vitro and in vivo". Drug Metabolism and Disposition. 34 (4): 583–590.
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