Field safety and effectiveness of new visceral leishmaniasis treatment regimens within public health facilities in Bihar, India

The status of combination therapy for visceral leishmaniasis: an updated review

For the past 15 years, trials of combination therapy options for visceral leishmaniasis have been conducted with the aim of identifying effective, and safe treatment regimens that were shorter than existing monotherapy regimens and could also prevent or delay the emergence of drug resistance. Although first-line treatment currently relies on combination therapy in east Africa, this is not true in Latin America owing to disappointing trial results, with lower than expected efficacy seen for the combination treatment group. By contrast, several effective combination therapy regimens have been identified through trials on the Indian subcontinent; yet, first-line therapy is still AmBisome monotherapy as the drug is part of a free donation programme and is highly effective in this region. Achieving a short all-oral combination treatment will require new chemical entities, several of which are currently under evaluation. Future studies should systematically include pharmacological substudies to ensure optimal dosing for all patient groups. To achieve maximal impact of new combination treatments, mechanisms to ensure drug availability and access after trials should be established. Enhancing the longevity of current and novel treatments will require effective systems for early detection of emerging drug resistance.

Paromomycin and Miltefosine Combination as an Alternative to Treat Patients With Visceral Leishmaniasis in Eastern Africa: A Randomized, Controlled, Multicountry Trial

BACKGROUND

This study aimed to determine whether paromomycin plus miltefosine (PM/MF) is noninferior to sodium stibogluconate plus paromomycin (SSG/PM) for treatment of primary visceral leishmaniasis in eastern Africa.

METHODS

An open-label, phase 3, randomized, controlled trial was conducted in adult and pediatric patients at 7 sites in eastern Africa. Patients were randomly assigned to either 20 mg/kg paromomycin plus allometric dose of miltefosine (14 days), or 20 mg/kg sodium stibogluconate plus 15 mg/kg paromomycin (17 days). The primary endpoint was definitive cure after 6 months.

RESULTS

Of 439 randomized patients, 424 completed the trial. Definitive cure at 6 months was 91.2% (155 of 170) and 91.8% (156 of 170) in the PM/MF and SSG/PM arms in primary efficacy modified intention-to-treat analysis (difference, 0.6%; 97.5% confidence interval [CI], -6.2 to 7.4), narrowly missing the noninferiority margin of 7%. In the per-protocol analysis, efficacy was 92% (149 of 162) and 91.7% (155 of 169) in the PM/MF and SSG/PM arms (difference, -0.3%; 97.5% CI, -7.0 to 6.5), demonstrating noninferiority. Treatments were well tolerated. Four of 18 serious adverse events were study drug-related, and 1 death was SSG-related. Allometric dosing ensured similar MF exposure in children (<12 years) and adults.

CONCLUSIONS

PM/MF and SSG/PM efficacies were similar, and adverse drug reactions were as expected given the drugs safety profiles. With 1 less injection each day, reduced treatment duration, and no risk of SSG-associated life-threatening cardiotoxicity, PM/MF is a more patient-friendly alternative for children and adults with primary visceral leishmaniasis in eastern Africa.

CLINICAL TRIALS REGISTRATION

NCT03129646.

Epidemiological and clinical factors associated with lethality from Human Visceral Leishmaniasis in Northeastern Brazil, 2007 to 2018

Human Visceral Leishmaniasis (HVL) presents a subacute clinical evolution with systemic involvement, which can result in high case fatality, especially among untreated individuals or those with low socioeconomic status. This study aimed to identify epidemiological and clinical factors associated with HVL case fatality in the Ceara State, from 2007 to 2018. This is an analytical cross-sectional study. The bivariate analysis was performed by Stata 15.1 using Pearson’s Chi-square or Fisher’s exact test; and Poisson regression for age-controlled multivariate analysis. From 2007 to 2018, there were 4,863 new confirmed cases and 343 deaths from HVL (case fatality rate=7.05%). The risk factors associated with case fatalities were: age group (RR=8.69; 95%CI:3.56-21.20); black population (RR=2.21; 95%CI:1.45-3.35); jaundice symptoms (RR=1.72; 95%CI:1.38-2.14); edema (RR=2.62; 95%CI:2.10-3.26) and hemorrhagic phenomena (RR=1.63; 95%CI:1.26-2.10); and no prescription drug intake (RR=4.03; 95%CI:2.98-5.46). Treatment with pentavalent antimonial was a protective factor (RR=0.35; 95%CI:0.27-0.45). The number of deaths increased among the elderly, illiterate, urban residents, and black skin color individuals. The drugs pentavalent antimonial and amphotericin B showed an association with death, but were not considered causal factors. Treatment failure led to a high risk of death. In multivariate analysis, the risk factors for fatal cases were age group, black skin, symptoms of jaundice, edema and hemorrhagic phenomena; and failure to take the prescription drugs. Treatment with pentavalent antimonial was shown to be a protective factor. Knowing the factors associated with the fatality of VL-HIV cases may help to improve public policies, in order to refine the epidemiological surveillance program and, consequently, prevent deaths related to the disease in Ceara.

Road-map of pre-clinical treatment for Visceral Leishmaniasis

Visceral leishmaniasis (VL) or Kala-azar, is the most lethal form of leishmaniasis, is still prevalent in many countries where it is endemic. It is a threat to human life caused by protozoan parasite Leishmania donovani. The severity of the disease is further increased as the treated individuals might have a chance of developing Post Kala-azar Dermal Leishmaniasis (PKDL) in the long run. Moreover, several countries have reported high number of HIV-VL co-infected patients. Therefore, there is a dire need for the development of efficient diagnostic methods and drugs in order to combat the disease and to control the spread of disease. At present, the treatment for VL entirely relies on therapeutic drugs as no vaccine is available yet. Ever since 1900s a series of drugs have been invented and used for treatment of VL; but the need for one such cost-effective treatment that would completely cure the disease with minimal side-effects, low relapse rate with high efficacy and less toxicity remains yet to be fulfilled. Therefore, identifying novel compounds is very crucial to develop potent antileishmanial agents. Thus, this review enlists several instances of drug development, including the pharmacokinetic and pharmacodynamic properties of antileishmanial drugs, different experimental animal models used to investigate the disease progression and to analyze treatment dosage and pharmacological aspect of drugs. Furthermore, the existing gap in drug development and future measures to improve the process are also discussed in this review.

Antiprotozoal agents: How have they changed over a decade?

Neglected tropical diseases are a diverse group of communicable diseases that are endemic in low- or low-to-middle-income countries located in tropical and subtropical zones. The number and availability of drugs for treating these diseases are low, the administration route is inconvenient in some cases, and most of them have safety, efficacy, or adverse/toxic reaction issues. The need for developing new drugs to deal with these issues is clear, but one of the most drastic consequences of this negligence is the lack of interest in the research and development of new therapeutic options among major pharmaceutical companies. Positive changes have been achieved over the last few years, although the overall situation remains alarming. After more than one decade since the original work reviewing antiprotozoal agents came to light, now it is time to question ourselves: How has the scenario for the treatment of protozoal diseases such as malaria, leishmaniasis, human African trypanosomiasis, and American trypanosomiasis changed? This review covers the last decade in terms of the drugs currently available for the treatment of these diseases as well as the clinical candidates being currently investigated.

Visceral Leishmaniasis in pregnancy and vertical transmission: A systematic literature review on the therapeutic orphans

Background

Reports on the occurrence and outcome of Visceral Leishmaniasis (VL) in pregnant women is rare in published literature. The occurrence of VL in pregnancy is not systematically captured and cases are rarely followed-up to detect consequences of infection and treatment on the pregnant women and foetus.

Methods

A review of all published literature was undertaken to identify cases of VL infections among pregnant women by searching the following database: Ovid MEDLINE; Ovid Embase; Cochrane Database of Systematic Reviews; Cochrane Central Register of Controlled Trials; World Health Organization Global Index Medicus: LILACS (Americas); IMSEAR (South-East Asia); IMEMR (Eastern Mediterranean); WPRIM (Western Pacific); ClinicalTrials.gov; and the WHO International Clinical Trials Registry Platform. Selection criteria included any clinical reports describing the disease in pregnancy or vertical transmission of the disease in humans. Articles meeting pre-specified inclusion criteria and non-primary research articles such as textbook, chapters, letters, retrospective case description, or reports of accidental inclusion in trials were also considered.

Results

The systematic literature search identified 272 unique articles of which 54 records were included in this review; a further 18 records were identified from additional search of the references of the included studies or from personal communication leading to a total of 72 records (71 case reports/case series; 1 retrospective cohort study; 1926–2020) describing 451 cases of VL in pregnant women. The disease was detected during pregnancy in 398 (88.2%), retrospectively confirmed after giving birth in 52 (11.5%), and the time of identification was not clear in 1 (0.2%). Of the 398 pregnant women whose infection was identified during pregnancy, 346 (86.9%) received a treatment, 3 (0.8%) were untreated, and the treatment status was not clear in the remaining 49 (12.3%). Of 346 pregnant women, Liposomal amphotericin B (L-AmB) was administered in 202 (58.4%) and pentavalent antimony (PA) in 93 (26.9%). Outcomes were reported in 176 pregnant women treated with L-AmB with 4 (2.3%) reports of maternal deaths, 5 (2.8%) miscarriages, and 2 (1.1%) foetal death/stillbirth. For PA, outcomes were reported in 88 of whom 4 (4.5%) died, 24 (27.3%) had spontaneous abortion, 2 (2.3%) had miscarriages. A total of 26 cases of confirmed, probable or suspected cases of vertical transmission were identified with a median detection time of 6 months (range: 0–18 months).

Conclusions

Outcomes of VL treatment during pregnancy is rarely reported and under-researched. The reported articles were mainly case reports and case series and the reported information was often incomplete. From the studies identified, it is difficult to derive a generalisable information on outcomes for pregnant women and babies, although reported data favours the usage of liposomal amphotericin B for the treatment of VL in pregnant women.

Visceral Leishmaniasis (VL) is a neglected tropical disease with an estimated incidence of 50,000 to 90,000 cases in 2019. Women who are susceptible to becoming pregnant or those who are pregnant and lactating are regularly excluded from clinical studies of VL. A specific concern of public health relevance is the little knowledge of the consequences of VL and its treatment on the mother and the foetus. We did a systematic review of all published literature with an overarching aim of identifying cases of VL in pregnancy and assessing the risk-benefit balance of antileishmanial treatment to the pregnant women and the child. We identified a total of 72 records (1926–2020) describing 451 VL cases in pregnant women. In 398, infection was identified during pregnancy of whom 202 received Liposomal Amphotericin B (L-AmB) and 93 received pentavalent antimony (PA). In studies that reported maternal outcomes, reports of maternal death abortion/spontaneous abortion, and miscarriages were proportionally lower among those who received L-AmB compared to PA (no formal test of significance carried out). A total of 26 cases of confirmed, probable or suspected cases of vertical transmission were identified and the median time to detection was 6 months (range: 0–18 months). Our review brings together scattered observations of VL in pregnant women in the clinical literature and clearly highlights that the disease in pregnancy is under-reported and under-studied. The collated evidence derived mainly from case reports and case series indicate that L-AmB has a favourable safety profile than the antimony regimen and should be the preferred treatment for VL during pregnancy.

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.

Treatment With Liposomal Amphotericin B for All Confirmed Cases of Human Visceral Leishmaniasis in Brazil: A Budget Impact Analysis

OBJECTIVES

To estimate the budget impact of the expansion of liposomal amphotericin B use for all confirmed cases of visceral leishmaniasis (VL) in Brazil. Currently, the first-line medicine for VL treatment is meglumine antimoniate. Liposomal amphotericin B is indicated only for patients with a greater risk of severity by the disease.

METHODS

The analysis was performed from the perspective of the Brazilian public healthcare system over 3 years, considering the following 2 scenarios: the reference scenario with the current recommendations for VL treatment and the alternative scenario based on the use of liposomal amphotericin B for all patients. A diffusion rate of 60% was used in the first year, 80% in the second year, and 100% in the third year. The epidemiological parameters used in the analysis came from the Notifiable Diseases Information System and from a clinical trial that evaluated the efficacy and safety of medicines for the treatment of VL in the country. The costs were related to the treatment of VL and to hospital and outpatient care.

RESULTS

In the reference scenario, the total cost for treatment of the 3453 VL confirmed cases in 2014 was $1 447 611.75. The incremental budget impact with the use of liposomal amphotericin B for all the VL confirmed cases was $299 646.43 in the third year.

CONCLUSIONS

The analysis presented will support the decision process for the use and expansion of liposomal amphotericin B for all VL confirmed cases in Brazil.

Long-term incidence of relapse and post-kala-azar dermal leishmaniasis after three different visceral leishmaniasis treatment regimens in Bihar, India

Background

Few prospective data exist on incidence of post kala-azar dermal leishmaniasis (PKDL) and visceral leishmaniasis (VL) relapse after different treatment regimens.

Methodology/Principal findings

A Phase IV trial included 1761 VL patients treated between 2012–2014 with single dose AmBisome (SDA; N = 891), miltefosine-paromomycin (Milt-PM; n = 512), or AmBisome-miltefosine (AmB-Milt; n = 358). Follow-up for PKDL and VL relapse was scheduled for 6, 12 and 24 months after treatment, lasting until 2017. Patients with lesions consistent with PKDL were tested by rK39 rapid test, and if positive, underwent skin-snip sampling, smear microscopy and PCR. Probable PKDL was defined by consistent lesions and positive rK39; confirmed PKDL required additional positive microscopy or PCR. PKDL and relapse incidence density were calculated by VL treatment and risk factors evaluated in Cox proportional hazards models.

Among 1,750 patients who completed treatment, 79 had relapse and 104 PKDL. Relapse incidence density was 1.58, 2.08 and 0.40 per 1000 person-months for SDA, AmB-Milt and Milt-PM, respectively. PKDL incidence density was 1.29, 1.45 and 2.65 per 1000 person-months for SDA, AmB-Milt and Milt-PM. In multivariable models, patients treated with Milt-PM had lower relapse but higher PKDL incidence than those treated with SDA; AmB-Milt rates were not significantly different from those for SDA. Children <12 years were at higher risk for both outcomes; females had a higher risk of PKDL but not relapse.

Conclusions/Significance

Active surveillance for PKDL and relapse, followed by timely treatment, is essential to sustain the achievements of VL elimination programs in the Indian sub-continent.

Efforts to eliminate visceral leishmaniasis (VL) in the Indian subcontinent have had an unprecedented impact on the number of cases over the past decade, however, the disease is known to be cyclical and previous periods of low incidence have been followed by a major resurgence. The disease is thought to be maintained between epidemics as post-kala-azar dermal leishmaniasis (PKDL), a skin disease affecting 5 to 15% of apparently cured VL patients in the Indian subcontinent. PKDL is difficult to cure and since PKDL patients are not systemically ill, they seldom seek treatment, meaning that PKDL is likely to be a major obstacle to elimination. A key question is how different VL treatment regimens affect the risk of subsequent PKDL. We followed-up a cohort of more than 1700 patients treated with three different drug regimens in an effectiveness trial in Bihar and found that patients treated with miltefosine-paromomycin had a lower risk of relapse but higher PKDL incidence, while AmBisome treated patients had the reverse pattern. In order to sustain the gains already made, active surveillance for PKDL and relapse is essential, along with timely treatment, and new VL treatment regimens that avoid future PKDL are needed.

Effectiveness of Single-Dose Liposomal Amphotericin B in Visceral Leishmaniasis in Bihar

Liposomal amphotericin B (LAmB) is recommended for treatment of Indian visceral leishmaniasis (VL), with a cure rate of more than 95% in the Indian subcontinent. A prospective observational study of 1,143 subjects was performed with a longer follow-up than prior studies (12 months) to evaluate the long-term effectiveness and safety of LAmB for the treatment of VL. Patients received a single dose of 10 mg/kg LAmB and were evaluated for initial cure at day 30 and final cure at 6 and 12 months to see the response to the therapy. Furthermore, predictors of relapse were also calculated. At day 30, the initial cure rate was 100%; however, at 6 months and 12 months, cure rates were 97.0% and 94.2% by per-protocol analysis and 96.9% and 93.9% by intension-to-treat analysis, respectively. Fever was the most common adverse event (AE). There were no deaths and serious AEs. Male gender, weight less than 30 kg, and spleen size more than 4 cm at the start of the treatment were significant risk factors of relapse. Liposomal amphotericin B was found to be very effective and safe in the treatment of VL. A longer follow-up period of 12 months is recommended to pick up late relapses.

Outwitting an Old Neglected Nemesis: A Review on Leveraging Integrated Data-Driven Approaches to Aid in Unraveling of Leishmanicides of Therapeutic Potential

The global prevalence of leishmaniasis has increased with skyrocketed mortality in the past decade. The causative agent of leishmaniasis is Leishmania species, which infects populations in almost all the continents. Prevailing treatment regimens are consistently inefficient with reported side effects, toxicity and drug resistance. This review complements existing ones by discussing the current state of treatment options, therapeutic bottlenecks including chemoresistance and toxicity, as well as drug targets. It further highlights innovative applications of nanotherapeutics-based formulations, inhibitory potential of leishmanicides, anti-microbial peptides and organometallic compounds on leishmanial species. Moreover, it provides essential insights into recent machine learning-based models that have been used to predict novel leishmanicides and also discusses other new models that could be adopted to develop fast, efficient, robust and novel algorithms to aid in unraveling the next generation of anti-leishmanial drugs. A plethora of enriched functional genomic, proteomic, structural biology, high throughput bioassay and drug-related datasets are currently warehoused in both general and leishmania-specific databases. The warehoused datasets are essential inputs for training and testing algorithms to augment the prediction of biotherapeutic entities. In addition, we demonstrate how pharmacoinformatics techniques including ligand-, structure- and pharmacophore-based virtual screening approaches have been utilized to screen ligand libraries against both modeled and experimentally solved 3D structures of essential drug targets. In the era of data-driven decision-making, we believe that highlighting intricately linked topical issues relevant to leishmanial drug discovery offers a one-stop-shop opportunity to decipher critical literature with the potential to unlock implicit breakthroughs.

Field effectiveness of new visceral leishmaniasis regimens after 1 year following treatment within public health facilities in Bihar, India

BACKGROUND

An earlier open label, prospective, non-randomized, non-comparative, multi-centric study conducted within public health facilities in Bihar, India (CTRI/2012/08/002891) measured the field effectiveness of three new treatment regimens for visceral leishmaniasis (VL): single dose AmBisome (SDA), and combination therapies of AmBisome and miltefosine (AmB+Milt) and miltefosine and paromomycin (Milt+PM) up to 6 months follow-up. The National Vector Borne Disease Control Program (NVBDCP) recommended an extended follow up at 12 months post-treatment of the original study cohort to quantify late relapses.

METHODS

The 1,761 patients enrolled in the original study with the three new regimens were contacted and traced between 10 and 36 months following completion of treatment to determine their health status and any occurrence of VL relapse.

RESULTS

Of 1,761 patients enrolled in the original study, 1,368 were traced at the extended follow-up visit: 711 (80.5%), 295 (83.2%) and 362 (71.5%) patients treated with SDA, AmB+Milt and Milt+PM respectively. Of those traced, a total of 75 patients were reported to have relapsed by the extended follow-up; 45 (6.3%) in the SDA, 25 (8.5%) in the AmB+Milt and 5 (1.4%) in the Milt+PM arms. Of the 75 relapse cases, 55 had already been identified in the 6-months follow-up and 20 were identified as new cases of relapse at extended follow-up; 7 in the SDA, 10 in the AmB+Milt and 3 in the Milt+PM arms.

CONCLUSION

Extending follow-up beyond the standard 6 months identified additional relapses, suggesting that 12-month sentinel follow-up may be useful as a programmatic tool to better identify and quantify relapses. With limited drug options, there remains an urgent need to develop effective new chemical entities (NCEs) for VL.

Chemogenomic Profiling of Antileishmanial Efficacy and Resistance in the Related Kinetoplastid Parasite Trypanosoma brucei

The arsenal of drugs used to treat leishmaniasis, caused by Leishmania spp., is limited and beset by toxicity and emergent resistance. Furthermore, our understanding of drug mode of action and potential routes to resistance is limited. Forward genetic approaches have revolutionized our understanding of drug mode of action in the related kinetoplastid parasite Trypanosoma brucei.

The arsenal of drugs used to treat leishmaniasis, caused by Leishmania spp., is limited and beset by toxicity and emergent resistance. Furthermore, our understanding of drug mode of action and potential routes to resistance is limited. Forward genetic approaches have revolutionized our understanding of drug mode of action in the related kinetoplastid parasite Trypanosoma brucei. Therefore, we screened our genome-scale T. brucei RNA interference (RNAi) library against the current antileishmanial drugs sodium stibogluconate (antimonial), paromomycin, miltefosine, and amphotericin B. Identification of T. brucei orthologues of the known Leishmania antimonial and miltefosine plasma membrane transporters effectively validated our approach, while a cohort of 42 novel drug efficacy determinants provides new insights and serves as a resource. Follow-up analyses revealed the antimonial selectivity of the aquaglyceroporin TbAQP3. A lysosomal major facilitator superfamily transporter contributes to paromomycin-aminoglycoside efficacy. The vesicle-associated membrane protein TbVAMP7B and a flippase contribute to amphotericin B and miltefosine action and are potential cross-resistance determinants. Finally, multiple phospholipid-transporting flippases, including the T. brucei orthologue of the Leishmania miltefosine transporter, a putative β-subunit/CDC50 cofactor, and additional membrane-associated hits, affect amphotericin B efficacy, providing new insights into mechanisms of drug uptake and action. The findings from this orthology-based chemogenomic profiling approach substantially advance our understanding of antileishmanial drug action and potential resistance mechanisms and should facilitate the development of improved therapies as well as surveillance for drug-resistant parasites.