The initial effectiveness of liposomal amphotericin B (AmBisome) and miltefosine combination for treatment of visceral leishmaniasis in HIV co-infected patients in Ethiopia: A retrospective cohort study

Hematological and Clinical Features Associated with Initial Poor Treatment Outcomes in Visceral Leishmaniasis Patients with and without HIV Coinfection in Gondar, Northwest Ethiopia

Ethiopia is among the countries with a high leishmaniasis burden. In this retrospective review, we aimed to determine hematological and clinical features associated with initial poor treatment outcomes of visceral leishmaniasis (VL) patients. The majority of VL cases in this study had leucopenia (94.3%), thrombocytopenia (87.1%), and anemia (85.9%). HIV coinfection was present in 7.0% (n = 23) of VL cases. At the center, VL patients without HIV coinfection were treated with sodium stibogluconate and paromomycin combination, whereas HIV coinfected cases were treated with AmBisome and miltefosine combination therapy. End-of-treatment cure rates among HIV-positive and HIV-negative visceral leishmaniasis cases, respectively, were 52.2% and 96.9%. Case fatality rates were 34.8% and 2.7% in HIV-positive and HIV-negative cases, respectively. Overall, non-survivors in this study were more likely to have HIV (55.0% vs. 4.1%, p < 0.001), sepsis (15.0% vs. 1.4%, p = 0.019), and dyspnea (40.0% vs. 2.7%, p < 0.001) at admission. In this regard, particular attention to the management of superimposed disease conditions at admission, including sepsis, HIV, and dyspnea, is needed to improve VL patients’ treatment outcomes. The inadequacy of the current treatments, i.e., AmBisome and miltefosine combination therapy, for HIV coinfected visceral leishmaniasis patients requires further attention as it calls for new treatment modalities.

Following successful anti-leishmanial treatment, neutrophil counts, CD10 expression and phagocytic capacity remain reduced in visceral leishmaniasis patients co-infected with HIV

Visceral leishmaniasis (VL) patients co-infected with HIV (VL/HIV patients) experience frequent treatment failures, VL relapses, opportunistic infections, and higher mortality. Their immune system remains profoundly suppressed after clinical cure and they maintain higher parasite load. This is in contrast with patients with VL alone (VL patients). Since neutrophils play a critical role in the control of Leishmania replication and the regulation of immune responses, we tested the hypothesis that neutrophil activation status and effector functions are fully restored in VL, but not in VL/HIV patients. Our results show the neutrophil counts and all activation markers and effector functions tested in our study were reduced at the time of diagnosis in VL and VL/HIV patients as compared to controls. CD62L, CD63, arginase 1 expression levels and reactive oxygen species production were restored at the end of treatment in both groups. However, neutrophil counts, CD10 expression and phagocytosis remained significantly lower throughout follow-up in VL/HIV patients; suggesting that dysregulated neutrophils contribute to the impaired host defence against pathogens in VL/HIV patients.

Metagenomic Analysis Identifying a Rare Leishmania Infection in an Adult With AIDS

Leishmania belongs to a genus of the protozoan parasites that causes leishmaniasis, and includes cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL). In this case, Leishmania amastigotes were found on cytomorphology examination of the bone marrow specimen, followed by 1,076 Leishmania donovani reads using metagenomic next generation sequencing (mNGS). Since being definitely diagnosed with VL/HIV coinfection, the patient was treated with liposomal amphotericin B as the parasite-resistant therapy and was discharged after clinical cure. But nearly a year later, on the mNGS follow-up, L. donovani was detected in the patient’s blood plasma specimen with 941 reads, suggesting that a relapse of leishmaniasis had occurred. These results indicate that leishmaniasis still exists in China and may represent a public health concern. This case could be helpful in the differential diagnosis of leishmaniasis, and for determining disease progression, prevention, and control of vectors and reservoir hosts.

Immunological factors, but not clinical features, predict visceral leishmaniasis relapse in patients co-infected with HIV

Visceral leishmaniasis (VL) has emerged as a clinically important opportunistic infection in HIV patients, as VL/HIV co-infected patients suffer from frequent VL relapse. Here, we follow cohorts of VL patients with or without HIV in Ethiopia. By the end of the study, 78.1% of VL/HIV-but none of the VL patients-experience VL relapse. Despite a clinically defined cure, VL/HIV patients maintain higher parasite loads, lower BMI, hepatosplenomegaly, and pancytopenia. We identify three immunological markers associated with VL relapse in VL/HIV patients: (1) failure to restore antigen-specific production of IFN-γ, (2) persistently lower CD4+ T cell counts, and (3) higher expression of PD1 on CD4+ and CD8+ T cells. We show that these three markers, which can be measured in primary hospital settings in Ethiopia, combine well in predicting VL relapse. The use of our prediction model has the potential to improve disease management and patient care.

Oral combination of eugenol oleate and miltefosine induce immune response during experimental visceral leishmaniasis through nitric oxide generation with advanced cytokine demand

Conventional therapy of visceral leishmaniasis (VL) remains challenging with the pitfall of toxicity, drug resistance, and expensive. Hence, urgent need for an alternative approach is essential. In this study, we evaluated the potential of combination therapy with eugenol oleate and miltefosine in Leishmania donovani infected macrophages and in the BALB/c mouse model. The interactions between eugenol oleate and miltefosine were found to be additive against promastigotes and amastigotes with xΣFIC 1.13 and 0.68, respectively. Significantly (p < 0.001) decreased arginase activity, increased nitrite generation, improved pro-inflammatory cytokines, and phosphorylated p38MAPK were observed after combination therapy with eugenol oleate and miltefosine. >80% parasite clearance in splenic and hepatic tissue with concomitant nitrite generation, and anti-VL cytokines productions were observed after orally administered miltefosine (5 mg/kg body weight) and eugenol oleate (15 mg/kg body weight) in L. donovani-infected BALB/c mice. Altogether, this study suggested the possibility of an oral combination of miltefosine with eugenol oleate against visceral leishmaniasis.

Serious adverse events following treatment of visceral leishmaniasis: A systematic review and meta-analysis

Background

Despite a historical association with poor tolerability, a comprehensive review on safety of antileishmanial chemotherapies is lacking. We carried out an update of a previous systematic review of all published clinical trials in visceral leishmaniasis (VL) from 1980 to 2019 to document any reported serious adverse events (SAEs).

Methods

For this updated systematic review, we searched the following databases from 1^st Jan 2016 through 2^nd of May 2019: PUBMED, Embase, Scopus, Web of Science, Cochrane, clinicaltrials.gov, WHO ICTRP, and the Global Index Medicus. We included randomised and non-randomised interventional studies aimed at assessing therapeutic efficacy and extracted the number of SAEs reported within the first 30 days of treatment initiation. The incidence rate of death (IRD) from individual treatment arms were combined in a meta-analysis using random effects Poisson regression.

Results

We identified 157 published studies enrolling 35,376 patients in 347 treatment arms. Pentavalent antimony was administered in 74 (21.3%), multiple-dose liposomal amphotericin B (L-AmB) in 52 (15.0%), amphotericin b deoxycholate in 51 (14.7%), miltefosine in 33 (9.5%), amphotericin b fat/lipid/colloid/cholesterol in 31 (8.9%), and single-dose L-AmB in 17 (4.9%) arms. There was a total of 804 SAEs reported of which 793 (including 428 deaths) were extracted at study arm level (11 SAEs were reported at study level only). During the first 30 days, there were 285 (66.6%) deaths with the overall IRD estimated at 0.068 [95% confidence interval (CI): 0.041–0.114; I² = 81.4%; 95% prediction interval (PI): 0.001–2.779] per 1,000 person-days at risk; the rate was 0.628 [95% CI: 0.368–1.021; I² = 82.5%] in Eastern Africa, and 0.041 [95% CI: 0.021–0.081; I² = 68.1%] in the Indian Subcontinent. In 21 study arms which clearly indicated allowing the inclusion of patients with HIV co-infections the IRD was 0.575 [95% CI: 0.244–1.355; I² = 91.9%] compared to 0.043 [95% CI: 0.020–0.090; I² = 62.5%] in 160 arms which excluded HIV co-infections.

Conclusion

Mortality within the first 30 days of VL treatment initiation was a rarely reported event in clinical trials with an overall estimated rate of 0.068 deaths per 1,000 person-days at risk, though it varied across regions and patient populations. These estimates may serve as a benchmark for future trials against which mortality data from prospective and pharmacovigilance studies can be compared. The methodological limitations exposed by our review support the need to assemble individual patient data (IPD) to conduct robust IPD meta-analyses and generate stronger evidence from existing trials to support treatment guidelines and guide future research.

Visceral leishmaniasis, also known as Kala-Azar, is a neglected infectious disease of poverty affecting countries in the Indian Subcontinent and Eastern Africa. Existing treatments have concerning safety profiles and are far from ideal, with documented reports of serious adverse events (SAEs) following therapy. We did a systematic review of all published clinical trials in VL (1980–2019) to document SAEs following treatment administration reported in clinical literature and carried out a meta-analysis to quantify the incidence rate of mortality within 30 days of treatment initiation. We found that safety outcomes are poorly reported in published literature with substantial missing information regarding timing and frequency of the events. We also observed that mortality following treatment with antileishmanial drugs, as reported in the literature, is a rare event. There was substantial variability in mortality rates across geographical regions and patient sub-groups. Results from this review can provide benchmark estimates for comparing data from prospective trials and pharmacovigilance studies and support the need to assemble individual patient data (IPD) to conduct a robust IPD meta-analyses to overcome some of the underlying limitations.

The global procurement landscape of leishmaniasis medicines

Ensuring access to essential medicines for leishmaniasis control is challenging, as leishmaniasis is a very small and unattractive market for pharmaceutical industry. Furthermore, control programmes are severely underfunded. We conducted an analysis of global procurement of leishmaniasis medicines for the past 5 years in order to shed light on the current leishmaniasis market landscape and supply and demand dynamics. We estimated global demand of each leishmaniasis medicines, the amount of each medicine required to treat all reported cases, based on the number of cases reported to WHO and the first-line treatment regimen used in each country. Procurement data were obtained from procurement agencies, international organizations, WHO, national leishmaniasis programmes and manufacturers. Expert interviews were conducted to have a better understanding of how medicines were procured and used. The comparison of estimated need and procurement data indicated discrepancies in supply and demand at global level as well as in the most endemic countries. The extent of the gap in supply was up to 80% of the needs for one of the leishmaniasis medicines. Mismatch between supply and demand was much wider for cutaneous leishmaniasis than visceral leishmaniasis. This study presents a current picture of procurement patterns and imbalance in global supply and demand. Addressing improved access and supply barriers requires concerted and coordinated efforts at the global and national levels. Priority actions include setting up a procurement coordination mechanism among major procurers, partners and national programmes where forecasting and supply planning is jointly developed and communicated with manufacturers. In addition, continuous engagement of manufacturers and advocacy is critical to diversify the supplier base and ensure quality-assured and affordable generic medicines for leishmaniasis.

Trypanosomatid-Caused Conditions: State of the Art of Therapeutics and Potential Applications of Lipid-Based Nanocarriers

Trypanosomatid-caused conditions (African trypanosomiasis, Chagas disease, and leishmaniasis) are neglected tropical infectious diseases that mainly affect socioeconomically vulnerable populations. The available therapeutics display substantial limitations, among them limited efficacy, safety issues, drug resistance, and, in some cases, inconvenient routes of administration, which made the scenarios with insufficient health infrastructure settings inconvenient. Pharmaceutical nanocarriers may provide solutions to some of these obstacles, improving the efficacy-safety balance and tolerability to therapeutic interventions. Here, we overview the state of the art of therapeutics for trypanosomatid-caused diseases (including approved drugs and drugs undergoing clinical trials) and the literature on nanolipid pharmaceutical carriers encapsulating approved and non-approved drugs for these diseases. Numerous studies have focused on the obtention and preclinical assessment of lipid nanocarriers, particularly those addressing the two currently most challenging trypanosomatid-caused diseases, Chagas disease, and leishmaniasis. In general, in vitro and in vivo studies suggest that delivering the drugs using such type of nanocarriers could improve the efficacy-safety balance, diminishing cytotoxicity and organ toxicity, especially in leishmaniasis. This constitutes a very relevant outcome, as it opens the possibility to extended treatment regimens and improved compliance. Despite these advances, last-generation nanosystems, such as targeted nanocarriers and hybrid systems, have still not been extensively explored in the field of trypanosomatid-caused conditions and represent promising opportunities for future developments. The potential use of nanotechnology in extended, well-tolerated drug regimens is particularly interesting in the light of recent descriptions of quiescent/dormant stages of Leishmania and Trypanosoma cruzi, which have been linked to therapeutic failure.

Prognostic factors for mortality among patients with visceral leishmaniasis in East Africa: Systematic review and meta-analysis

BACKGROUND

Visceral leishmaniasis (VL) is a vector-borne disease that is deadly if left untreated. Understanding which factors have prognostic value may help to focus clinical management and reduce case fatality. However, information about prognostic factors is scattered and conflicting. We conducted a systematic review and meta-analysis to identify prognostic factors for mortality among VL patients in East Africa.

METHODOLOGY/PRINCIPAL FINDINGS

The review protocol was registered in PROSPERO (CRD42016043112). We included studies published in English after 1970 describing VL patients treated in East African health facilities. To be included, studies had to report on associations between clinical or laboratory factors and mortality during admission or during VL treatment, with a minimal study size of ten patients. Conference abstracts and evaluations of genetic or immunological prognostic factors were excluded. We searched for studies in MEDLINE and four other databases in December 2018. To assess the risk of bias in observational studies and clinical trials, we used the Quality in Prognostic Studies (QUIPS) tool. We included 48 studies in the systematic review, describing 150,072 VL patients of whom 7,847 (5.2%) died. Twelve prognostic factors were evaluated in five or more studies and these results were submitted to meta-analysis producing one pooled crude odds ratio (OR) per prognostic factor. The following factors were strongly (OR>3) and significantly (P-value<0.05) associated with mortality: jaundice (OR = 8.27), HIV (OR = 4.60), tuberculosis (OR = 4.06), age >45 years (OR = 3.69), oedema (OR = 3.52), bleeding (OR = 3.37), and haemoglobin ≤6.5 g/dl (OR = 3.26). Factors significantly and moderately (OR between one and three) associated with death were severe malnutrition, long duration of illness, young age (<5 years), and large spleen size.

CONCLUSIONS/SIGNIFICANCE

These prognostic factors can be identified by health professionals in resource-constrained settings. They should be considered as "core" prognostic factors in future studies that aim at improving the prognosis of VL patients.

An unusual case of post-kala-azar dermal leishmaniasis in a patient with HIV and visceral leishmaniasis co-infection

Visceral leishmaniasis (VL) is a vector-borne disease caused by Leishmania donovani complex. Post-kala-azar dermal leishmaniasis (PKDL) is a rash that can occur following treatment for VL due to L. donovani species. We describe an unusual case of PKDL occurring during treatment for Leishmania infantum VL in a patient with human immunodeficiency virus-co infection.

Severe post-kala-azar dermal leishmaniasis successfully treated with miltefosine in an Ethiopian HIV patient

Post-kala-azar dermal leishmaniasis (PKDL) is a neglected tropical disease characterized by a dermatosis which often appears after successful treatment of visceral leishmaniasis caused by Leishmania donovani. PKDL treatment options are few and have severe limitations. In East-Africa, the standard treatment of PKDL is with daily painful potentially toxic sodium stibogluconate injections, administered for a prolonged duration of 30-60 days. In the Indian subcontinent, PKDL is mainly treated with miltefosine, a safer orally administered drug. However, in East-Africa, there is very limited experience in the use of miltefosine for treatment of severe PKDL, with only one published case report. Here we report a severe PKDL case in an Ethiopian HIV patient successfully treated with oral miltefosine (100mg/day for 28 days). Miltefosine was efficacious, safe and well tolerated, suggesting that it can play an important role in the treatment of severe PKDL also in East-African patients. Further research is warranted.

Chemoinformatics Strategies for Leishmaniasis Drug Discovery

Leishmaniasis is a fatal neglected tropical disease (NTD) that is caused by more than 20 species of Leishmania parasites. The disease kills approximately 20,000 people each year and more than 1 billion are susceptible to infection. Although counting on a few compounds, the therapeutic arsenal faces some drawbacks such as drug resistance, toxicity issues, high treatment costs, and accessibility problems, which highlight the need for novel treatment options. Worldwide efforts have been made to that aim and, as well as in other therapeutic areas, chemoinformatics have contributed significantly to leishmaniasis drug discovery. Breakthrough advances in the comprehension of the parasites’ molecular biology have enabled the design of high-affinity ligands for a number of macromolecular targets. In addition, the use of chemoinformatics has allowed highly accurate predictions of biological activity and physicochemical and pharmacokinetics properties of novel antileishmanial compounds. This review puts into perspective the current context of leishmaniasis drug discovery and focuses on the use of chemoinformatics to develop better therapies for this life-threatening condition.