Topical terbinafine in the treatment of cutaneous leishmaniasis: triple blind randomized clinical trial

Examination of the Topical Effect of the Combination of Plantago ovata and Vinegar on the Improvement of Rural Cutaneous Leishmaniasis Lesions

Background

The present study aimed at investigating the topical effect of the combination of Plantago ovata and vinegar on the improvement of rural cutaneous leishmaniasis lesions.

Materials and Methods

The present randomized double-blind controlled clinical trial was performed on 42 patients with rural skin leishmaniasis. In the case group, in addition to injecting glucantime into the lesion according to the latest national instructions, a combination of P. ovata and vinegar was applied topically twice a day for 8 weeks. In the control group, only glucantime injection into the lesion was performed for 8 weeks according to the latest national guidelines. At the end of the 1^st, 2^nd, 3^rd, 4^th, 8^th, and 12^th weeks after the intervention, the lesion area and improvement were evaluated and recorded.

Results

The results of the present study indicated the lesion area in the case group with the mean of 0.35 ± 0.39 cm and 0.18 ± 0.27 cm in the 8^th and 12^th weeks, respectively was significantly less than that of the control group with the mean of 0.64 ± 0.78 cm and 0.56 ± 0.44, respectively (P < 0.05). Twelve weeks after the intervention, 84.1% of the lesions in the case group and 65.9% of the lesions in the control group were completely improved (P < 0.05).

Conclusion

According to the results of the present study, the improvement of leishmaniasis lesion with the topical application of the combination of P. ovata and vinegar was significantly more than that of the control group in the 8^th and 12^th weeks after the intervention.

An appraisal of the scientific current situation and new perspectives in the treatment of cutaneous leishmaniasis

Leishmaniasis is a Neglected Tropical Diseases caused by protozoan parasites of the genus Leishmania. It is a major health problem in many tropical and subtropical regions of the world and can produce three different clinical manifestations, among which cutaneous leishmaniasis has a higher incidence in the world than the other clinical forms. There are no recognized and reliable means of chemoprophylaxis or vaccination against infections with different forms of leishmaniasis. In addition, chemotherapy, unfortunately, remains, in many respects, unsatisfactory. Therefore, there is a continuing and urgent need for new therapies against leishmaniasis that are safe and effective in inducing a long-term cure. This review summarizes the latest advances in currently available treatments and improvements in the development of drug administration. In addition, an analysis of the in vivo assays was performed and the challenges facing promising strategies to treat CL are discussed. The treatment of leishmaniasis will most likely evolve into an approach that uses multiple therapies simultaneously to reduce the possibility of developing drug resistance. There is a continuous effort to discover new drugs to improve the treatment of leishmaniasis, but this is mainly at the level of individual researchers. Undoubtedly, more funding is needed in this area, as well as greater participation of the pharmaceutical industry to focus efforts on the development of chemotherapeutic agents and vaccines for this and other neglected tropical diseases.

Safety and efficacy of allylamines in the treatment of cutaneous and mucocutaneous leishmaniasis: A systematic review

Cutaneous and mucocutaneous leishmaniasis affect a million people yearly, leading to skin lesions and potentially disfiguring mucosal disease. Current treatments can have severe side effects. Allylamine drugs, like terbinafine, are safe, including during pregnancy. This review assesses efficacy and safety of allylamines for the treatment of cutaneous and mucocutaneous leishmaniasis. It followed the PRISMA statement for reporting and was preregistered in PROSPERO(CRD4201809068). MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, the Global Health Library, Web of Science, Google Scholar, and clinical trial registers were searched from their creation to May 24^th, 2020. All original human, animal, and in vitro studies concerning allylamines and cutaneous or mucocutaneous leishmaniasis were eligible for inclusion. Comparators—if any—included both placebo or alternative cutaneous or mucocutaneous leishmaniasis treatments. Complete cure, growth inhibition, or adverse events served as outcomes. The search identified 312 publications, of which 22 were included in this systematic review. There were one uncontrolled and two randomised controlled trials. The only well-designed randomised controlled trial that compared the treatment efficacy of oral terbinafine versus intramuscular meglumine antimoniate in 80 Leismania tropica infected patients showed a non-significant lower cure rate for terbinafine vs meglumine antimoniate (38% vs 53%). A meta-analysis could not be performed due to the small number of studies, their heterogeneity, and low quality. This systematic review shows that there is no evidence of efficacy of allylamine monotherapy against cutaneous and mucocutaneous leishmaniasis. Further trials of allylamines should be carefully considered as the outcomes of an adequately designed trial were disappointing and in vitro studies indicate minimal effective concentrations that are not achieved in the skin during standard doses. However, the in vitro synergistic effects of allylamines combined with triazole drugs warrant further exploration.

Nanoemulsified Butenafine for Enhanced Performance against Experimental Cutaneous Leishmaniasis

The production of ergosterol lipid involves the activity of different enzymes and is a crucial event for the Leishmania membrane homeostasis. Such enzymes can be blocked by azoles and allylamines drugs, such as the antifungal butenafine chloride. This drug was active on parasites that cause cutaneous and visceral leishmaniasis. Based on the leishmanicidal activity of butenafine chloride and considering the absence of reports about the therapeutic potential of this drug in cutaneous leishmaniasis, the present work is aimed at analyzing the efficacy of butenafine formulated in two different topical delivery systems, the self-nanoemulsifying drug delivery systems (BUT-SNEDDS) and in a SNEDDS-based nanogel (BUT-SNEDDS gel) as well as in the free form in experimental cutaneous leishmaniasis. Physical studies showed that both formulations were below 300 nm with low polydispersity (<0.5) and good colloidal stability (around -25 mV). Increased steady-state flux was reported for nanoenabled butenafine formulations with reduced lag time in Franz cell diffusion assays across Strat-M membranes. No toxic or inflammatory reactions were detected in animals treated with BUT-SNEDDS, BUT-SNEDDS gel, or butenafine. Animals topically treated with butenafine (free or nanoformulated) showed small dermal lesions and low tissue parasitism. Furthermore, BUT-SNEDD gel and butenafine presented similar efficacy than the standard drug Glucantime given by the intralesional route. Increased levels of IFN-γ were observed in animals treated with BUT-SNEDDS gel or butenafine. Based on these data, the antifungal drug butenafine chloride can be considered an interesting repurposed drug for the treatment of cutaneous leishmaniasis.

Tolnaftate inhibits ergosterol production and impacts cell viability of Leishmania sp

Leishmaniasis is an infectious disease caused by protozoan parasites of the genus Leishmania. The treatment of all forms of leishmaniasis relies on first-line drug, pentavalent antimonial, and in cases of drug failure, the second-line drug amphotericin B has been used. Besides the high toxicity of drugs, parasites can be resistant to antimonial in some areas of the World, making it necessary to perform further studies for the characterization of new antileishmanial agents. Thus, the aim of the present work was to evaluate the leishmanicidal activity of tolnaftate, a selective reversible and non-competitive inhibitor of the fungal enzyme squalene epoxidase, which is involved in the biosynthesis of ergosterol, essential to maintain membrane physiology in fungi as well as trypanosomatids. Tolnaftate eliminated promastigote forms of L. (L.) amazonensis, L. (V.) braziliensis and L. (L.) infantum (EC₅₀ ~ 10 μg/mL and SI ~ 20 for all leishmanial species), and intracellular amastigote forms of all studied species (EC₅₀ ~ 23 μg/mL in infections caused by dermatotropic species; and 11.7 μg/mL in infection caused by viscerotropic species) with high selectivity toward parasites [SI ~ 8 in infections caused by dermatotropic species and 17.4 for viscerotropic specie]. Promastigote forms of L. (L.) amazonensis treated with the EC₅₀ of tolnaftate displayed morphological and physiological changes in the mitochondria and cell membrane. Additionally, promastigote forms treated with tolnaftate EC₅₀ reduced the level of ergosterol by 5.6 times in comparison to the control parasites. Altogether, these results suggest that tolnaftate has leishmanicidal activity towards Leishmania sp., is selective, affects the cell membrane and mitochondria of parasites and, moreover, inhibits ergosterol production in L. (L.) amazonensis.

CpG ODN D35 improves the response to abbreviated low-dose pentavalent antimonial treatment in non-human primate model of cutaneous leishmaniasis

Cutaneous leishmaniasis (CL) affects the lives of 0.7–1 million people every year causing lesions that take months to heal. These lesions can result in disfiguring scars with psychological, social and economic consequences. Antimonials are the first line of therapy for CL, however the treatment is lengthy and linked to significant toxicities; further, its efficacy is variable and resistant parasites are emerging. Shorter or lower dose antimonial treatment regimens, which would decrease the risk of adverse events and improve patient compliance, have shown reduced efficacy and further increase the risk emergence of antimonial-resistant strains. The progression of lesions in CL is partly determined by the immune response it elicits, and previous studies showed that administration of immunomodulatory type D CpG ODNs, magnifies the immune response to Leishmania and reduces lesion severity in nonhuman primates (NHP) challenged with Leishmania major or Leishmania amazonensis. Here we explored whether the addition of a single dose of immunomodulating CpG ODN D35 augments the efficacy of a short-course, low-dose pentavalent antimonial treatment regimen. Results show that macaques treated with D35 plus 5mg/kg sodium stibogluconate (Sb^V) for 10 days had smaller lesions and reduced time to re-epithelization after infection with Leishmania major. No toxicities were evident during the studies, even at doses of D35 10 times higher than those used in treatment. Critically, pentavalent antimonial treatment did not modify the ability of D35 to induce type I IFNs. The findings support the efficacy of D35 as adjuvant therapy for shorter, low dose pentavalent antimonial treatment.

Cutaneous leishmaniasis is a devastating disease that affects close to a million people every year. Its clinical presentation ranges from small uncomplicated lesions that heal over a few months to debilitating large chronic or recurring lesions that result in disfigurement, stigma, and economic loss. Antimonials are the first line treatment for cutaneous leishmaniasis in most countries, but the lengthy treatment schedules, significant associated toxicities, and the emergence of resistant strains, require the development of alternative strategies. As the immune response is a key determinant of disease course, immunomodulatory therapies could be harnessed to act in concert with antimonials to improve the safety and efficacy of CL treatment. Synthetic oligonucleotide D35 selectively activates plasmacytoid dendritic cells and was previously shown to reduce the severity of L. major and L. amazonensis lesions in rhesus macaques, but its activity in combination with antimonials was unknown. Our studies show that a single subcutaneous dose of innate immune modulator D35 improved the response to a low-dose abbreviated antimonial course, reducing the severity of the lesions and accelerating healing in primates. No toxicities were evident with D35 at doses ten-fold higher than the effective dose. The studies suggest that the combined therapy strategy shows clinical promise.

Exploiting knowledge on pharmacodynamics-pharmacokinetics for accelerated anti-leishmanial drug discovery/development

Introduction: Being on the top list of neglected tropical diseases, leishmaniasis has been marked for elimination by 2020. In the light of small armamentarium of drugs and their associated drawbacks, the understanding of pharmacodynamics and/or pharmacokinetics becomes a priority to achieve and sustain disease elimination. Areas covered: The authors have looked into pharmacological aspects of existing and emerging drugs for treatment of leishmaniasis. An in-depth understanding of pharmacodynamics and pharmacokinetics (PKPD) provides a rationale for drug designing and optimizing the treatment strategies. It forms a key to prevent drug resistance and avoid drug-associated adverse effects. The authors have compiled the researches on the PKPD of different anti-leishmanial formulations that have the potential for improved and/or effective disease intervention. Expert opinion: Understanding the pharmacological aspects of drugs forms the basis for the clinical application of novel drugs. Tailoring drug dosage and individualized treatment can avoid the adverse events and bridge gap between the in vitro models and their clinical application. An integrated approach, with pragmatic use of technological advances can improve phenotypic screening and physiochemical properties of novel drugs. Concomitantly, this can serve to improve clinical efficacies, reduce the incidence of relapse and accelerate the drug discovery/development process for leishmaniasis elimination.

Leishmanicidal effects of amphotericin B in combination with selenium loaded on niosome against Leishmania tropica

The strategy for improving the treatment of leishmaniasis by the World Health Organization, is the development of new drugs and combination therapy. The aim of this survey was to investigate the effect of amphotericin B (AmB) in combination with selenium, in a simple or niosomal form, on Leishmania tropica (L. tropica) by in vitro advanced assays. In this study, a niosomal formulation of AmB with selenium was prepared and characterized based on size and morphology. Using MTT assay, macrophage model, flow cytometry, and qPCR, the cytotoxicity and efficiency of the niosomal formulation and simple form of combination were evaluated. No toxicity was reported for both the niosomal and simple form of the combination. The niosomal formulation significantly showed higher inhibitory effect on the promastigote and amastigote forms of L. tropica than simple combination form. Interleukin (IL)-10 significantly decreased while the level of IL-12 and metacasoase as Th-1 activator significantly increased (P < 0.001). The findings of this study indicated that niosomes are the stable carriers for this combination, easy to produce and provide promising results as an effective formulation in the inhibition of extracellular and intracellular forms of L. tropica in compared with simple combination form.

Interventions for Old World cutaneous leishmaniasis

BACKGROUND

Cutaneous leishmaniasis, caused by a parasitic infection, is considered one of the most serious skin diseases in many low- and middle-income countries. Old World cutaneous leishmaniasis (OWCL) is caused by species found in Africa, Asia, the Middle East, the Mediterranean, and India. The most commonly prescribed treatments are antimonials, but other drugs have been used with varying success. As OWCL tends to heal spontaneously, it is necessary to justify the use of systemic and topical treatments. This is an update of a Cochrane Review first published in 2008.

OBJECTIVES

To assess the effects of therapeutic interventions for the localised form of Old World cutaneous leishmaniasis.

SEARCH METHODS

We updated our searches of the following databases to November 2016: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We also searched five trials registers and checked the reference lists of included studies for further references to relevant randomised controlled trials (RCTs). We wrote to national programme managers, general co-ordinators, directors, clinicians, WHO-EMRO regional officers of endemic countries, pharmaceutical companies, tropical medicine centres, and authors of relevant papers for further information about relevant unpublished and ongoing trials. We undertook a separate search for adverse effects of interventions for Old World cutaneous leishmaniasis in September 2015 using MEDLINE.

SELECTION CRITERIA

Randomised controlled trials of either single or combination treatments in immunocompetent people with OWCL confirmed by smear, histology, culture, or polymerase chain reaction. The comparators were either no treatment, placebo/vehicle, and/or another active compound.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias and extracted data. We only synthesised data when we were able to identify at least two studies investigating similar treatments and reporting data amenable to pooling. We also recorded data about adverse effects from the corresponding search.

MAIN RESULTS

We included 89 studies (of which 40 were new to this update) in 10,583 people with OWCL. The studies included were conducted mainly in the Far or Middle East at regional hospitals, local healthcare clinics, and skin disease research centres. Women accounted for 41.5% of the participants (range: 23% to 80%). The overall mean age of participants was 25 years (range 12 to 56). Most studies lasted between two to six months, with the longest lasting two years; average duration was four months. Most studies were at unclear or high risk for most bias domains. A lack of blinding and reporting bias were present in almost 40% of studies. Two trials were at low risk of bias for all domains. Trials reported the causative species poorly.Here we provide results for the two main comparisons identified: itraconazole (200 mg for six to eight weeks) versus placebo; and paromomycin ointment (15% plus 10% urea, twice daily for 14 days) versus vehicle.In the comparison of oral itraconazole versus placebo, at 2.5 months' follow up, 85/125 participants in the itraconazole group achieved complete cure compared to 54/119 in the placebo group (RR 3.70, 95% CI 0.35 to 38.99; 3 studies; 244 participants). In one study, microbiological or histopathological cure of skin lesions only occurred in the itraconazole group after a mean follow-up of 2.5 months (RR 17.00, 95% CI 0.47 to 612.21; 20 participants). However, although the analyses favour oral itraconazole for these outcomes, we cannot be confident in the results due to the very low certainty evidence. More side effects of mild abdominal pain and nausea (RR 2.36, 95% CI 0.74 to 7.47; 3 studies; 204 participants) and mild abnormal liver function (RR 3.08, 95% CI 0.53 to 17.98; 3 studies; 84 participants) occurred in the itraconazole group (as well as reports of headaches and dizziness), compared with the placebo group, but again we rated the certainty of evidence as very low so are unsure of the results.When comparing paromomycin with vehicle, there was no difference in the number of participants who achieved complete cure (RR of 1.00, 95% CI 0.86, 1.17; 383 participants, 2 studies) and microbiological or histopathological cure of skin lesions after a mean follow-up of 2.5 months (RR 1.03, CI 0.88 to 1.20; 383 participants, 2 studies), but the paromomycin group had more skin/local reactions (such as inflammation, vesiculation, pain, redness, or itch) (RR 1.42, 95% CI 0.67 to 3.01; 4 studies; 713 participants). For all of these outcomes, the certainty of evidence was very low, meaning we are unsure about these results.Trial authors did not report the percentage of lesions cured after the end of treatment or speed of healing for either of these key comparisons.

AUTHORS' CONCLUSIONS

There was very low-certainty evidence to support the effectiveness of itraconazole and paromomycin ointment for OWCL in terms of cure (i.e. microbiological or histopathological cure and percentage of participants completely cured). Both of these interventions incited more adverse effects, which were mild in nature, than their comparisons, but we could draw no conclusions regarding safety due to the very low certainty of the evidence for this outcome.We downgraded the key outcomes in these two comparisons due to high risk of bias, inconsistency between the results, and imprecision. There is a need for large, well-designed international studies that evaluate long-term effects of current therapies and enable a reliable conclusion about treatments. Future trials should specify the species of leishmaniasis; trials on types caused by Leishmania infantum, L aethiopica, andL donovani are lacking. Research into the effects of treating women of childbearing age, children, people with comorbid conditions, and those who are immunocompromised would also be helpful.It was difficult to evaluate the overall efficacy of any of the numerous treatments due to the variable treatment regimens examined and because RCTs evaluated different Leishmania species and took place in different geographical areas. Some outcomes we looked for but did not find were degree of functional and aesthetic impairment, change in ability to detect Leishmania, quality of life, and emergence of resistance. There were only limited data on prevention of scarring.

Interventions for Old World cutaneous leishmaniasis

BACKGROUND

Cutaneous leishmaniasis, caused by a parasitic infection, is considered one of the most serious skin diseases in many low- and middle-income countries. Old World cutaneous leishmaniasis (OWCL) is caused by species found in Africa, Asia, the Middle East, the Mediterranean, and India. The most commonly prescribed treatments are antimonials, but other drugs have been used with varying success. As OWCL tends to heal spontaneously, it is necessary to justify the use of systemic and topical treatments. This is an update of a Cochrane Review first published in 2008.

OBJECTIVES

To assess the effects of therapeutic interventions for the localised form of Old World cutaneous leishmaniasis.

SEARCH METHODS

We updated our searches of the following databases to November 2016: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, and LILACS. We also searched five trials registers and checked the reference lists of included studies for further references to relevant randomised controlled trials (RCTs). We wrote to national programme managers, general co-ordinators, directors, clinicians, WHO-EMRO regional officers of endemic countries, pharmaceutical companies, tropical medicine centres, and authors of relevant papers for further information about relevant unpublished and ongoing trials. We undertook a separate search for adverse effects of interventions for Old World cutaneous leishmaniasis in September 2015 using MEDLINE.

SELECTION CRITERIA

Randomised controlled trials of either single or combination treatments in immunocompetent people with OWCL confirmed by smear, histology, culture, or polymerase chain reaction. The comparators were either no treatment, placebo/vehicle, and/or another active compound.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias and extracted data. We only synthesised data when we were able to identify at least two studies investigating similar treatments and reporting data amenable to pooling. We also recorded data about adverse effects from the corresponding search.

MAIN RESULTS

We included 89 studies (of which 40 were new to this update) in 10,583 people with OWCL. The studies included were conducted mainly in the Far or Middle East at regional hospitals, local healthcare clinics, and skin disease research centres. Women accounted for 41.5% of the participants (range: 23% to 80%). The overall mean age of participants was 25 years (range 12 to 56). Most studies lasted between two to six months, with the longest lasting two years; average duration was four months. Most studies were at unclear or high risk for most bias domains. A lack of blinding and reporting bias were present in almost 40% of studies. Two trials were at low risk of bias for all domains. Trials reported the causative species poorly.Here we provide results for the two main comparisons identified: itraconazole (200 mg for six to eight weeks) versus placebo; and paromomycin ointment (15% plus 10% urea, twice daily for 14 days) versus vehicle.In the comparison of oral itraconazole versus placebo, at 2.5 months' follow up, 85/125 participants in the itraconazole group achieved complete cure compared to 54/119 in the placebo group (RR 3.70, 95% CI 0.35 to 38.99; 3 studies; 244 participants). In one study, microbiological or histopathological cure of skin lesions only occurred in the itraconazole group after a mean follow-up of 2.5 months (RR 17.00, 95% CI 0.47 to 612.21; 20 participants). However, although the analyses favour oral itraconazole for these outcomes, we cannot be confident in the results due to the very low certainty evidence. More side effects of mild abdominal pain and nausea (RR 2.36, 95% CI 0.74 to 7.47; 3 studies; 204 participants) and mild abnormal liver function (RR 3.08, 95% CI 0.53 to 17.98; 3 studies; 84 participants) occurred in the itraconazole group (as well as reports of headaches and dizziness), compared with the placebo group, but again we rated the certainty of evidence as very low so are unsure of the results.When comparing paromomycin with vehicle, there was no difference in the number of participants who achieved complete cure (RR of 1.00, 95% CI 0.86, 1.17; 383 participants, 2 studies) and microbiological or histopathological cure of skin lesions after a mean follow-up of 2.5 months (RR 1.03, CI 0.88 to 1.20; 383 participants, 2 studies), but the paromomycin group had more skin/local reactions (such as inflammation, vesiculation, pain, redness, or itch) (RR 1.42, 95% CI 0.67 to 3.01; 4 studies; 713 participants). For all of these outcomes, the certainty of evidence was very low, meaning we are unsure about these results.Trial authors did not report the percentage of lesions cured after the end of treatment or speed of healing for either of these key comparisons.

AUTHORS' CONCLUSIONS

There was very low-certainty evidence to support the effectiveness of itraconazole and paromomycin ointment for OWCL in terms of cure (i.e. microbiological or histopathological cure and percentage of participants completely cured). Both of these interventions incited more adverse effects, which were mild in nature, than their comparisons, but we could draw no conclusions regarding safety due to the very low certainty of the evidence for this outcome.We downgraded the key outcomes in these two comparisons due to high risk of bias, inconsistency between the results, and imprecision. There is a need for large, well-designed international studies that evaluate long-term effects of current therapies and enable a reliable conclusion about treatments. Future trials should specify the species of leishmaniasis; trials on types caused by Leishmania infantum, L aethiopica, andL donovani are lacking. Research into the effects of treating women of childbearing age, children, people with comorbid conditions, and those who are immunocompromised would also be helpful.It was difficult to evaluate the overall efficacy of any of the numerous treatments due to the variable treatment regimens examined and because RCTs evaluated different Leishmania species and took place in different geographical areas. Some outcomes we looked for but did not find were degree of functional and aesthetic impairment, change in ability to detect Leishmania, quality of life, and emergence of resistance. There were only limited data on prevention of scarring.