Mycosis fungoides responding to systemic itraconazole

Itraconazole in the Treatment of Nonfungal Cutaneous Diseases: A Review

INTRODUCTION

The anti-inflammatory and pro-kinetic properties of antibiotics have been widely reported. However, the non-antifungal properties of antifungal agents are less well known and less explored in clinical practice. The purpose of this review was to survey the literature on the non-antifungal use of itraconazole in dermatological practice and the possible modes of action of this agent.

METHODS

The PubMed database was searched for relevant articles published up to January 2017. The references in the articles identified by the search were then hand-searched for additional relevant publications.

RESULTS

Itraconazole displays a great diversity of non-antifungal activity and has been used to treat a broad spectrum of diseases. The results of our survey reveal that itraconazole has the potential to be an alternative agent for treating patients with advanced cancer (either alone or in combination with other cytotoxic chemotherapeutic drugs), especially those refractory to traditional treatments. Moreover, itraconazole acts as an anti-angiogenesis agent, induces nail growth, and modulates inflammatory or immune diseases.

CONCLUSION

Oral antifungal agents have many non-antifungal properties. However, the body of evidence on individual agents often remains limited due to the lack of large-scale randomized controlled studies. Although some of the findings published to date seem promising, pharmacological vigilance should be taken for off-label use in real-world practice.

Repurposing itraconazole for the treatment of cancer

The repurposing of drugs is becoming increasingly attractive as it avoids the lengthy process and cost implications associated with bringing a novel drug to market. Itraconazole is a broad-spectrum anti-fungal agent. An emerging body of in vivo, in vitro and clinical evidence have confirmed that it also possesses antineoplastic activities and has a synergistic action when combined with other chemotherapeutic agents. It acts via several mechanisms to prevent tumour growth, including inhibition of the Hedgehog pathway, prevention of angiogenesis, decreased endothelial cell proliferation, cell cycle arrest and induction of auto-phagocytosis. These allow itraconazole, either alone or in combination with other cytotoxic agents, to increase drug efficacy and overcome drug resistance. This study reviews the reported literature on the use of itraconazole in a variety of malignancies and highlights the recent insights into the critical pathways acted upon to prevent tumour growth.

Repurposing Drugs in Oncology (ReDO)-itraconazole as an anti-cancer agent

Itraconazole, a common triazole anti-fungal drug in widespread clinical use, has evidence of clinical activity that is of interest in oncology. There is evidence that at the clinically relevant doses, itraconazole has potent anti-angiogenic activity, and that it can inhibit the Hedgehog signalling pathway and may also induce autophagic growth arrest. The evidence for these anticancer effects, in vitro, in vivo, and clinical are summarised, and the putative mechanisms of their action outlined. Clinical trials have shown that patients with prostate, lung, and basal cell carcinoma have benefited from treatment with itraconazole, and there are additional reports of activity in leukaemia, ovarian, breast, and pancreatic cancers. Given the evidence presented, a case is made that itraconazole warrants further clinical investigation as an anti- cancer agent. Additionally, based on the properties summarised previously, it is proposed that itraconazole may synergise with a range of other drugs to enhance the anti-cancer effect, and some of these possible combinations are presented in the supplementary materials accompanying this paper.