Treatment Options for Visceral Leishmaniasis: A Review of Medicines and Therapies

Visceral leishmaniasis (VL), also known as kala-azar, is a severe form of leishmaniasis caused by the Leishmania parasite. It primarily affects internal organs, particularly the spleen, liver, and bone marrow. While the disease is endemic in several parts of the world, particularly in the Mediterranean region, Africa, and parts of Asia, its impact is felt most acutely in impoverished communities where healthcare resources are limited. The progression of VL can be deadly if not treated promptly, leading to an urgent need for effective treatment options.

In recent years, advancements in the understanding of VL and its treatment have significantly improved patient outcomes. Various therapeutic approaches have been explored, ranging from traditional antimonials to newer lipid formulations. 

This blog explains the available treatment options for visceral leishmaniasis, examining their efficacy, mechanisms, and the challenges associated with their use.

What is visceral Leishmania caused by?

Visceral leishmaniasis is caused by the Leishmania parasites, which are transmitted through the bite of infected female phlebotomine sandflies. Once the parasites enter the human host, they invade macrophages, leading to symptoms such as fever, weight loss, anaemia, and splenomegaly. The disease can manifest in either acute or chronic forms, complicating both diagnosis and treatment. Early detection is vital to prevent severe health consequences linked with advanced stages of the disease.

Traditional treatment options for Visceral leishmaniasis

Historically, the primary treatment for VL has been pentavalent antimonials, such as sodium stibogluconate (SSG) and meglumine antimoniate. While these medications have been the cornerstone of therapy, they come with notable drawbacks, including toxicity, the requirement for intravenous administration, and growing resistance in some regions.

The emergence of medicine resistance has prompted the search for alternative therapies. Some of the older treatment options have been largely phased out due to their side effects and limited effectiveness in certain populations, highlighting the need for novel approaches.

What is the latest treatment for leishmaniasis?

The latest treatment for leishmaniasis includes the use of Ambisome 50mg Injection containing the active ingredient Liposomal Amphotericin B. This treatment has gained attention for its improved safety profile and effectiveness compared to traditional amphotericin B formulations. It is now a standard of care in many treatment guidelines, especially for patients who have experienced treatment failures or are at risk of complications from other medications.

The mechanism of action involves disrupting the cell membrane of Leishmania parasites, resulting in cell death. Administered intravenously, this treatment has demonstrated high cure rates, often exceeding 90%. Additionally, its reduced nephrotoxicity makes it a more suitable option for patients with compromised renal function.

Other modern treatment for leishmaniasis

In addition to traditional treatments, several other therapies are currently under investigation or have been adopted for use in specific contexts. These include:

• Miltefosine: Originally developed as an anticancer medicine, miltefosine has emerged as an oral treatment for visceral leishmaniasis. It is particularly valuable in regions where injectable therapies are less accessible. Studies have indicated that it can achieve high cure rates, although its teratogenic effects require careful consideration in women of childbearing age.

• Paromomycin: This aminoglycoside antibiotic has been used in combination with other treatments for VL, especially in resource-limited settings. It is administered intramuscularly and has shown promise in both monotherapy and combination regimens.

• Combination therapies: Recent research has emphasised the potential of combination therapies. These combinations can enhance efficacy and reduce the risk of medicine resistance, leading to improved clinical outcomes.

What are the complications in treating visceral leishmaniasis?

Despite the advancements in treatment options for visceral leishmaniasis, several challenges remain. The high cost of medications can limit access, particularly in endemic regions with limited healthcare budgets. Additionally, the need for specialised healthcare infrastructure to administer certain therapies complicates treatment logistics.

Medicine resistance is another growing concern, with some studies indicating decreased efficacy of established treatments. Continuous monitoring of treatment outcomes and the development of new therapeutic agents are critical in the ongoing battle against VL.

What antifungals are used to treat leishmaniasis?

While antileishmanial medicines are the primary treatment for visceral leishmaniasis, some antifungal medicines are being investigated for their potential efficacy. Compounds originally developed for fungal infections are showing promise due to overlapping mechanisms of action with leishmaniasis treatment. Integrating antifungals into the treatment regimen may provide new strategies to combat medicine resistance and enhance patient outcomes. Ongoing research aims to identify novel antifungal agents as valuable options for managing visceral leishmaniasis.

Wrapping up

Visceral leishmaniasis poses a significant public health challenge in endemic regions. Traditional treatments have been crucial, but the emergence of new therapies offers hope for better patient outcomes. This shift towards more effective and safer treatment options is promising. However, equitable access to these treatments remains essential. Addressing barriers to timely care is vital. With concerted efforts, we can make substantial progress against visceral leishmaniasis. Our ultimate goal is a future where this disease no longer threatens vulnerable populations.