The main objective of drug delivery systems is to deliver a drug effectively, specifically to the site of action and to achieve greater efficacy and minimise the toxic effects compared to conventional drugs. Amongst various carrier systems, liposomes have generated a great interest because of their versatility. Liposomes are vesicular concentric bilayered structures, which are biocompatible, biodegradable and nonimmumnogenic. They can control the delivery of drugs by targeting the drug to the site of action or by site avoidance drug delivery or by prolonged circulation of drugs. Amphotericin B (Amp B) remains the drug of choice in most systemic mycoses and also as a second line treatment for Kala azar. However, its toxic effects often limit its use. Although the liposome delivery system has been tried for several drugs, only a few have been used in patients due to the slow development of necessary large-scale pharmaceutical procedures. This paper reviews the development of the technique for liposomal Amphotericin B (L-Amp-LRC-1, FungisomeTM) drug delivery system in our laboratory in collaboration with the department of Biochemistry, Delhi University in India and proving the safety and efficacy of this preparation in clinical practice. It also attempts to compare the efficacy and benefits of our product for Indian patients with those of similar products and it includes facts from the publications that flowed from our work. As compared to conventional Amp B, Fungisome is infused over a much shorter period requiring a smaller volume and no premedication. It was found to be safe in patients who had developed serious unacceptable toxicity with conventional Amp B. In renal transplant patients, Fungisome did not produce any nephrotoxicity. Fungisome is effective in fungal infections resistant to fluconazole, conventional Amp B and in virgin and resistant cases of visceral leishmaniasis. The cost of any drug is of great significance, especially in India. We have therefore devoted a section of our review to the relative costs of our product and those of other commercially available products. This patient-worthy formulation is safe, efficacious and cheaper than the commercially available formulation of liposomal amphotericin B. The product has been patented and technology transferred to a pharmaceutical company for marketing. Results of postmarketing study also document safety and efficacy as observed in premarketing studies. A brief review of this work is provided here.

The increased incidence of systemic fungal infections in the past two decades has been overwhelming. Earlier, it was pathogenic dimorphic fungi, which were known to cause systemic infections. However, starting from the 1960s, opportunistic fungi started causing more number of infections, especially in the immunocompromised host. More recently, newer and less common fungal agents are being increasingly associated with infection in immunosuppressed hosts. Amongst dimorphic fungi, infections due to Histoplasma capsulatum and Penicillium marneffei are increasingly reported in patients with AIDS in India. H. capsulatum is found country wide, but P. marneffei remains restricted to Manipur state. Although both varieties of C. neoformans , C. neoformans var. neoformans (serotypes A & D), and C. neoformans var. gattii (serotypes B & C) are reported in India, most of the cases reported are of serotype A. Increased incidence of cryptococcosis is reported from all centers with the emergence of AIDS. Systemic infection due to species under Candida , Aspergillus and zygomycetes is widely prevalent in nosocomial setting, and outbreaks due to unusual fungi are reported occasionally from tertiary care centers. This global change in systemic fungal infections has emphasized the need to develop good diagnostic mycology laboratories in this country and to recognize this increasingly large group of potential fungal pathogens.

Cryptococcus neoformans is an important fungal pathogen causing invasive infection, especially of the central nervous system in this era of the HIV/AIDS epidemic. The choice of treatment depends on site(s) of infection and the patient's immune status. Use of appropriate antifungal agents decreases mortality significantly, but requires continued therapy and long-term maintenance to prevent relapses. The use of liposomal amphotericin B (L Amp B) has overcome some of the difficulties usually found in this setting. The major advantage of these liposomal formulations are faster clearance of C. neoformans [cerebrospinal fluid (CSF) negative] and a reduction in amphotericin toxicity. The majority of clinical efficacy data related to L Amp B are derived from compassionate use studies and case series. Use of liposomal amphotericin has also shown to be a cost effective approach.

Advances in neonatal management have led to considerable improvement in newborn survival. However, early (<72 hours) and late (>72hours) onset systemic infections, both bacterial and fungal, remain a devastating complication and an important cause of morbidity and mortality in these babies. Most neonatal fungal infections are due to Candida species, particularly Candida albicans. The sources of candidiasis in NICU are often endogenous following colonization of the babies with fungi. About 10% of these babies get colonized in first week of life and up to 64% babies get colonized by 4 weeks of hospital stay. Disseminated candidiasis presents like bacterial sepsis and can involve multiple organs such as the kidneys, brain, eye, liver, spleen, bone, joints, meninges and heart. Confirming the diagnosis by laboratory tests is difficult and a high index of suspicion is required. The diagnosis of fungemia can be made definitely only by recovering the organism from blood or other sterile bodily fluid. Amphotericin B continues to be the mainstay of therapy for systemic fungal infections but its use is limited by the risks of nephrotoxicity and hypokalemia. Newer formulations of amphotericin B, namely the liposomal and the lipid complex forms, have recently become available and have been reported to have lesser toxicity. More recently Indian liposomal Amphotericin B derived from neutral lipids (L-Amp -LRC-1) has shown good response with less toxicity. A clinical trial with this preparation has shown to be safe and efficacious in neonatal fungal infections. Compared to other liposomal preparations, L-Amp-LRC-1 is effective at lower dose and is less expensive drug for the treatment of neonatal candidiasis.

Invasive fungal infections are a major challenge in the management of immunocompromised patients and those with renal dysfunction. These challenges are due to the immense morbidity and mortality in such situations. Also the management strategies for invasive mycosis in patients with renal dysfunction have narrow safety profile and involve high-cost. In this review we will discuss the issues involved in the management of invasive mycosis in the patients with renal dysfunction in the form of acute renal failure, chronic kidney disease, dialysis dependency of renal transplant recipients. We also emphasize that the use of Intravenous Liposomal Amphoterecin appears to be an effective alternative to the conventional Amphoterecin B for the treatment of invasive fungal infections in patients with renal dysfunction due to its greatly improved tolerability profile. Commercially two true liposomal preparations (Fungisome and Ambisome) are available. Judgement about the preferred formulation should be made on the basis of disease morbidity, severity of renal dysfunction and the cost involved.

Fungal infections of the central nervous system (CNS) are almost always a clinical surprise. Their presentation is subtle, often without any diagnostic characteristics, and they are frequently mistaken for tuberculous meningitis, pyogenic abscess, or brain tumor. Granulocytopenia, cellular and humoral mediated immune dysfunction are predisposing factors to the development of CNS infections in immunosuppressed patients. Aspergillus fumigatus is the most common human pathogen in the genus Aspergillus .Maxillary sinusitis of dental origin or the lungs are the most common sites of primary Aspergillus infection. Infection reaches the brain directly from the nasal sinuses via vascular channels or is blood borne from the lungs and gastrointestinal tract. Single or multiple abscess formation with blood vessel invasion leading to thrombosis is a characteristic feature of Aspergillosis on neuropathologic examination. Aspergillosis should be considered in cases manifesting with acute onset of focal neurologic deficits resulting from a suspected vascular or space-occupying lesion especially in immunocompromised hosts. Aspergillosis is diagnosed on direct examinations and culture, however the diagnosis of aspergillosis of the CNS is difficult. Diagnosis of an intracranial mass lesion is best confirmed with a computed tomography or magnetic resonance imaging of the head with or without intravenous contrast. Aggressive neurosurgical intervention for surgical removal of Aspergillus abscesses, granulomas, and focally infracted brain; correction of underlying risk factors; Amphotericin B combined with flucytosine and treatment of the source of infection should form the mainstay of the management. Off late Liposomal Amphotericin B was found to be more effective and safe than conventional Amphotericin B in the management of Apergillus infections Only with a high index of suspicion, an aggressive approach to diagnosis, and rapid vigorous therapy may we hope to alter the clinical course in this group of patients.

Fever is the principle sign of infection in neutropenic patient and frequently may be the only evidence of infection. The pattern of fever in neutropenia is non-specific and not pathognomonic of any type of infections or non-infectious process and can be suppressed by the antipyretic effects of drugs such as corticosteroids. Neutropenia, resulting from cytotoxic chemotherapy is the most common risk factor for severe infections in hematological malignancies. The duration of neutropenia also contributes significantly to the risk of serious infections. This risk is significantly greater a lower neutrophil counts, such that 100% patients with ANC <100 cells/µl lasting 3 weeks or more develop documented infections. The prompt initiation of empirical antibiotics in febrile neutropenia has been the most important advance in the management of the immunocompromised host. The initial empirical antibiotic regimen started at presentation of the febrile episode frequently requires modifications especially in high-risk febrile neutropenia. Neutropenic patients who remain febrile despite 4-7 days of broad spectrum antibacterial therapy are at a high risk of invasive fungal infection. Empirical antifungal therapy with Amphotericin B in persistently febrile neutropenic patients and other high risk patients has shown to reduce the risk of invasive fungal infection by 50-80% and the risk of fungal infection related mortality by 23-45% in 1980's. The IDSA has recommended that amphotericin B at 0.5-0.7 mg/kg/day be administered till marrow recovery. This approach is limited however by the adverse effects caused by drug infusion (fever, chills, myalgias, nausea, hypotension and bronchospasm). Lipid formulations which improve the therapeutic ratio of the traditional formulation are available. The safety and efficacy of these formulations is well established. These formulations have comparable efficacy and are less nephrotoxic than conventional amphotericin B.A lipid formulation of amphotericin B is appropriate as initial empirical therapy or as definitive therapy for proven mycosis in high risk patients receiving concomitant nephrotoxic drugs (cyclosporine), those with pre-existing renal impairment and those with protracted neutropenia during which dose limiting toxicity may occur.

Increasing number of transplants worldwide has resulted in an increase in the incidence of fungal infections. Prolonged neutropenia, immunosuppression and graft vs. host disease all result in high predisposition to fungal infections. The likelihood of developing a fungal infection increases with the severity and duration of neutropenia, which, in the case of cancer or chemotherapy for the treatment of hematological malignancies, can range from a few days to several weeks. Invasive fungal infections are difficult to diagnose and neutropenic patients with fever often receive empirical antifungal therapy. This provides a rationale for the prophylactic use of antifungal agents. The empirical use of liposomal amphotericin B has overcome some of the difficulties usually found in this setting. The majority of clinical efficacy data related to liposomal amphotericin B are derived from compassionate use studies and case series. The major advantage of these liposomal formulations of amphotericin B is a reduction in amphotercin toxicity. Use of liposomal amphotericin has been shown to be a cost-effective approach abroad and the same has been our experience also. Commercially ambisome and Fungisome are the only products that contain true liposomes. Unlike ambisome, which needs to be used in dose of 3 mg/kg/day FungisomeTM is effective in the dose of 1-3 mg/kg bodyweight. The Indian liposomal preparation has shown to be safe and effective used in over 150 transplant patients in our experience. We conclude that the liposomal amphotericin is better-tolerated and also gives better responses in documented fungal infections.

Diagnosis and treatment of Indian visceral leishmaniasis (VL) is extremely unsatisfactory. For diagnosis, demonstration of parasites in splenic/marrow smears remains the gold standard, though k39 rapid strip test is a useful method in regions where access to parasite demonstration is difficult. pentavalent antimony remains the mainstay for the treatment of all forms of leishmaniasis globally; however, development of large-scale antimony resistance in Bihar has necessitated search for alternative drugs. Amphotericin B is the most effective, though toxic, drug for patients with refractory VL. Lipid formulations of amphotericin B, though safe and effective, are too expensive to be useful for poor patients of this region. These hold advantage as large quantity of the drug can safely be given over a short period of time, thus leading to a decrease in the hospital stay to a few days instead of several weeks. Oral miltefosine, an alkyl phospholipid, has recently been approved and marketed in India for the treatment of VL. Miltefosine cures 94% patients with VL if given in a daily dose of 50-100 mg for 28 days. Most common adverse events are mild vomiting and diarrhea. Paromomycin, an amino glycoside, is undergoing a pivotal phase-III clinical trial, and is likely to be approved and available to patients with VL at an affordable cost. To protect the already scarce inventory of antileishmanial drugs, it is time that combination chemotherapy is introduced for the treatment of VL in India.

Background : In May 2003, an indigenously developed liposomal amphotericin B (FungisomeTM) was introduced in the Indian market for the treatment of systemic fungal infections and visceral leishmaniasis. The present post marketing study assessed the safety and effectiveness of FungisomeTM in actual clinical practice. Setting and Design : Retrospective post marketing surveillance from four cities of India. Methods : The present study was carried out for a period of 6 months (Jun-Nov 2004), a year after the introduction of the drug. A list of doctors who had prescribed and procured the drug was obtained from the distributor. Consent to participate and scrutinize the patients' source notes were obtained from the concerned doctors. All patients who had received FungisomeTM treatment were included. Data was collected from the patient's source notes on a predesigned proforma. They were then analyzed by descriptive statistics. Cost of FungisomeTM was calculated on the basis of dose used and number of days of treatment Results : Data were available for 109/144 patients from 35/40 physicians. FungisomeTM was administered at 1-3 mg/kg/day for 7-76 days. No serious adverse events related to the drug were observed in the study. Mild infusion-related adverse events were reported in 40 (36% ), moderate in 11 (10%) of patients and severe in 2 (1.8% ). None of the adverse events were certain to FungisomeTM exposure, 12 (11 %) were probable, 28 (25 %) were possible, and 13 (11.9%) were unlikely. Of the 91 assessable patients (received at least eight doses of FungisomeTM) for efficacy complete response was observed in 67 (73.6%), 16 (17.5% ) had partial responses, and 8 (8.7%) of patients had no response. The acquisition cost per day and per course treatment of different fungal infections ranged from (apprx) Rs 4500-8000 and 0.9 -2.1 lakh respectively. Conclusion : This postmarketing study documents the safety, tolerability, effectiveness and cost advantage of indigenously developed liposomal amphotericin B in the treatment of systemic fungal infections and febrile neutropenia in actual clinical practice.