A randomized clinical trial comparing oral azithromycin and meglumine antimoniate for the treatment of American cutaneous leishmaniasis caused by Leishmania (Viannia) braziliensis

Azithromycin was compared with meglumine antimoniate for treatment of patients with cutaneous leishmaniasis. Patients were randomized to receive oral azithromycin, 500 mg/day (22 patients) or intramuscular meglumine antimoniate, 10 mg Sb/kg/day (23 patients), both for 28 days, with a second cycle of 15 days if necessary, and followed-up for one year after completion of treatment. Efficacy, defined as complete re-epithelization without relapse for 12 months after completing therapy, was 82.6% (95% confidence interval [CI] = 67-98%) for meglumine antimoniate and 45.5% (95% CI = 25-66%) for azithromycin. All patients who failed treatment with azithromycin were treated with meglumine antimoniate and clinically cured. Azithromycin was well tolerated; meglumine antimoniate caused arthralgias and local symptoms in 78% of the patients. In 17 cases, species identification was obtained; Leishmania (Viannia) braziliensis was identified in all of them. For the treatment of American cutaneous leishmaniasis caused by L. (V.) braziliensis, meglumine antimoniate is significatively more efficacious than azithromycin, which was clinically curative in almost half of the patients and well-tolerated.     

Systemic meglumine antimoniate in acute cutaneous leishmaniasis: children versus adults

Some studies showed that children have a lower response to systemic use of pentavalent antimoniate than adults. We aimed to evaluate the response rate to Glucantime therapy in children and compare it with adults. One hundred and twelve patients with acute cutaneous leishmaniasis: (ACL) were divided into two equal groups of adults (> 15 yrs) and children (≤ 15 yrs). They received meglumine antimoniate; 20 mg/kg/day for 20 days, their improvement rate was evaluated 20 and 45 days after treatment. Per-protocol analysis showed a significantly lower response in the children group 20 and 45 days after initiation of the treatment (P = 0.0001, 95% confidence interval [CI] = 0.190 [0.079-0.456]/P = 0.0051, 95% CI = 0.317 [0.140-0.717], respectively). Moreover, after intention-to-treat analysis, the same results were seen in the younger group 20 and 45 days after treatment (P = 0.0003, 95% CI = 0.228 [0.098-0.528]/P = 0.0132, 95% CI = 0.382 [0.177-0.825], respectively). According to our results, systemic Glucantime has lower efficacy in treating ACL in children than adults.     

Resistance to antimony and treatment failure in human Leishmania (Viannia) infection

BACKGROUND: Failure of antimonial therapy has been increasingly reported in anthroponotic visceral leishmaniasis and in cutaneous disease. The role of drug resistance in treatment failure has been difficult to ascertain because therapeutic response is multifactorial, and the efficacy of antimonial drugs depends on an effective immune response. In this study, we sought to determine whether standard treatment selects for resistant organisms and whether drug resistance contributes to treatment failure. METHODS: We evaluated the susceptibility to antimony of 19 strains isolated before treatment with meglumine antimoniate and 21 strains isolated at treatment failure from 20 patients. The 50% effective dose (ED50) of antimony in the form of additive-free meglumine antimoniate was determined for intracellular amastigotes in human promonocytic U-937 cells. RESULTS: Before treatment, 16% of strains (3/19) showed primary resistance (ED50 of >128 microg Sb/mL), whereas 84% (16/19) were susceptible (ED50 of <20 microg Sb/mL). However, 88% of susceptible strains (14/16) had ED90 values of >128 microg Sb/mL. At treatment failure, 40% of strains (8/20) were resistant. Secondary resistance was documented in 4 patients. CONCLUSIONS: Primary and secondary resistance to antimony can contribute to treatment failure in American cutaneous leishmaniasis. Selection for resistance to antimony occurs during standard treatment with antimonial drugs, and primary resistance to antimony supports the plausibility of anthroponotic transmission.     

Comparison of meglumine antimoniate and pentamidine for peruvian cutaneous leishmaniasis

Pentamidine was compared with meglumine antimoniate (Glucantime) for 80 patients with cutaneous leishmaniasis due to Leishmania braziliensis in Peru. Of the 40 patients administered Glucantime (20 mg of antimony [Sb]/kg/day intravenously for 20 days), 31 cured (78%), 6 failed (15%), of which 5 were due to relapse, and 3 were lost to follow-up (7%). Of the 40 patients administered pentamidine (2 mg/kg every other day for seven injections), 14 were cured (35%), 23 failed (58%), and 3 were lost to follow-up (7%). Five pentamidine failures were due to relapse, and 14 failures were due to the presence of parasites two weeks after therapy. Both regimens were well tolerated. Gastrointestinal, musculoskeletal, and total adverse events were not statistically different in either group. Elevations in levels of liver enzymes and pancreatic enzymes were statistically higher in the Glucantime group, but no patient terminated therapy prematurely. In this study, Glucantime was more effective than pentamidine for treatment of L. braziliensis cutaneous leishmaniasis in Peru based on parasitologic as well as clinical criteria.     

Treatment of visceral leishmaniasis in HIV-infected patients: a randomized trial comparing meglumine antimoniate with amphotericin B. Spanish HIV-Leishmania Study Group.

BACKGROUND: Visceral leishmaniasis is common in patients with HIV infection living in endemic areas, but the most effective and safe treatment remains unknown. OBJECTIVE: To compare the efficacy and safety of meglumine antimoniate versus amphotericin B in HIV-infected patients with first episodes of visceral leishmaniasis (VL). DESIGN: An open, multicentre, prospective and randomized trial. SETTING: Twelve tertiary hospitals. PATIENTS: Eighty-nine consecutive HIV-infected patients diagnosed with VL. Patients were randomly assigned to treatment with either meglumine antimoniate (20 mg pentavalent antimony per kilogram of body weight per day) or amphotericin B (0.7 mg/kg per day) both for 28 days. Treatment was considered successful if a bone marrow aspirate performed 1 month after the end of therapy did not detect parasites. Relapse was defined as the reappearance of parasites after an initial cure. RESULTS: An initial cure was attained in 29 of 44 patients (65.9%) randomly assigned to treatment with meglumine antimoniate and 28 of 45 (62.2%) randomly assigned to treatment with amphotericin B. The incidence of moderate to severe adverse events was similar in both groups. The patients treated with meglumine antimoniate had higher incidences of cardiotoxicity (14 versus 0%, P = 0.02) and chemical pancreatitis (30 versus 0%, P < 0.01). However, in the amphotericin B group, nephrotoxicity was more frequent (36 versus 5%, P < 0.01). There was no difference in survival or relapse-free interval according to the allocated group of therapy. CONCLUSION: Treatment of VL with meglumine antimoniate or amphotericin B was shown to have similar efficacy and toxicity rates in Spanish HIV-infected patients. The differences in the toxicity patterns could be useful in choosing one of these agents as first-line treatment.     

Decreased sensitivity to meglumine antimoniate (Glucantime) of Leishmania infantum isolated from dogs after several courses of drug treatment.

Although unresponsiveness to antimonial drugs in human leishmaniasis appears to be increasing, resistance to antimony in Leishmania is not well documented. Treatment of leishmaniasis in dogs, the domestic reservoir of L. infantum, with meglumine antimoniate (Glucantime) is a common practice in many Mediterranean countries. The dogs, however, remain highly infective to the phlebotomine vectors, even after several courses of treatment. A study was therefore carried out to test the comparative susceptibility to meglumine antimoniate of L. infantum stocks isolated from four naturally-infected dogs, before (BT) and after treatment (AT) with three to six courses of the drug, and used to infect Balb/c mice. Significant differences in suppression between the BT and AT stocks were observed in the infected mice when they were given the drug at a rate of 0.01-10 mg kg-1 day-1 for five days. Each AT stock was between eight and 41 times more resistant to meglumine antimoniate than the BT stock from the same dog, in terms of the ratios of the AT ED50 values to the corresponding BT values, which were calculated as indices of resistance. This result underlines the futility and danger of repeated antimonial treatments of dogs with signs of leishmaniasis, as these may produce a permanent reservoir of parasites unsusceptible to the drugs in human clinical use.     

Response of cutaneous leishmaniasis (chiclero's ulcer) to treatment with meglumine antimoniate in Southeast Mexico

Cutaneous leishmaniasis, known as chiclero's ulcer in southeastern Mexico, is characterized by a predominantly single, painless, ulcerated lesion, without lymphangitis or adenopathy. When located on the ear, it tends to become chronic, causing destruction of the pinna and disfigurement. It is caused predominantly by Leishmania (L.) mexicana. Although pentavalent antimonials (Sb5+) are the mainstay of leishmanial therapy and have been used for more than 50 years, dosage regimens have been repeatedly modified and the best one has not been fully identified. The main purpose of the present study was to investigate the response of chiclero's ulcer to treatment with meglumine antimoniate. One hundred five patients were treated with meglumine antimoniate at a daily dose of 1 ampule per day (425 mg of Sb5+) until healing. The lesions healed after a mean of 25 days (range = 5-60 days).     

Treatment failure in children in a randomized clinical trial with 10 and 20 days of meglumine antimonate for cutaneous leishmaniasis due to Leishmania viannia species.

Clinical response to supervised treatment of Colombian patients with cutaneous leishmaniasis was evaluated in a randomized controlled trial comparing 10 days versus 20 days of treatment with meglumine antimonate (20 mg Sb/kg/day). Masked examiners evaluated clinical response defined as 100% re-epithelialization of all lesions at 13 weeks and no relapses during 52 weeks of follow-up. The efficacy of meglumine antimonate for 10 days' treatment was 61% (28 of 46) compared to 67% (24 of 36) for 20 days. There was a significantly lower clinical response for children < 5 years in both 10-day (11%) and 20-day (25%) groups compared to patients aged 5-14 years (67% and 75%, respectively) and 15 years or more (81% and 83%, respectively). Overall efficacy of treatment schedules was comparable, but lower than expected, mainly because of low efficacy in children. Pathogenicity of infection and pharmacokinetics may affect the treatment response in children. New therapeutic alternatives should be evaluated in trials that include children and women.     

Failure of both azithromycin and antimony to treat cutaneous leishmaniasis in Manaus, AM, Brazil

A non-randomized controlled clinical trial was carried out in order to evaluate both azithromycin and antimony efficacy in cutaneous leishmaniasis in Manaus, AM, Brazil. Forty nine patients from both genders, aged 14 to 70, with cutaneous ulcers for less than three months and a positive imprint for Leishmania spp. amastigotes were recruited into two groups. Group I (26 patients) received a daily-single oral dose of 500 mg of azithromycin for 20 days and Group II (23 patients) received a daily-single intramuscular dose of 20 mg/kg of meglumine antimony, also for 20 days. Azithromycin cured three of 24 (12.5%) patients on days 60, 90 and 120 respectively whereas therapeutic failure was considered in 21 of 24 (87.5%) cases. In group II, antimony cured eight of 19 (42.1%) cases as follows: three on day 30, one each on day 60 and day 90, and three on day 120. Therapeutic failure occurred in 11 of 19 (57.9%) individuals. The efficacy of antimony for leishmaniasis was better than azithromycin but analysis for the intention-to-treat response rate did not show statistical difference between them. Although azithromycin was better tolerated, it showed a very low efficacy to treat cutaneous leishmaniasis in Manaus.     

Efficacy of Miltefosine for the Treatment of American Cutaneous Leishmaniasis

Miltefosine is an oral agent used for cutaneous leishmaniasis treatment. An open-label, randomized, phase III clinical trial was carried out in the Colombian army population. Miltefosine, 50 mg capsule was taken orally three times per day for 28 days (N = 145) or meglumine antimoniate, 20 mg/kg body weight per day for 20 days by intramuscular injection (N = 143). The efficacy of miltefosine by protocol was 69.8% (85/122 patients) and 58.6% (85/145 patients) by intention to treat. For meglumine antimoniate, the efficacy by protocol was 85.1% (103/121 patients) and 72% (103/143 patients) by intention to treat. No association was found between drug efficacy and L. (V.) braziliensis or L. (V.) panamensis species of Leishmania responsible for infection. Adverse gastrointestinal events were associated with the use of miltefosine, the meglumine antimoniate treatment was associated with adverse effects on the skeletal musculature, fever, cephalea, and higher toxicity in kidney, liver, pancreas, and hematological system.     

Possible links between sickle cell crisis and pentavalent antimony

For over 60 years, pentavalent antimony (Sb(v)) has been the first-line treatment of leishmaniasis. Sickle cell anemia is a disease caused by a defect in red blood cells, which among other things can cause vasooclusive crisis. We report the case of a 6-year-old child with leishmaniasis who during treatment with meglumine antimoniate developed a sickle cell crisis (SCC). No previous reports describing the relationship between antimonial drugs and sickle cell disease were found. Reviews of both the pathophysiology of SCC and the mechanism of action of Sb(v) revealed that a common pathway (glutathione) may have resulted in the SCC. ChemoText, a novel database created to predict chemical-protein-disease interactions, was used to perform a more expansive and systematic review that was able to support the association between glutathione, Sb(v), and SCC. Although suggestive evidence to support the hypothesis, additional research at the bench would be needed to prove Sb(v) caused the SCC.     

Pharmacokinetics of pentavalent antimony (Pentostam) in hamsters

Pentavalent antimony (Sb) is the classical treatment for visceral and cutaneous leishmaniasis. We investigated Sb levels in serum, liver, spleen, and skin of hamsters administered therapeutic dosages of Sb (600 and 300 mg Sb/kg). Single administration of Sb was more effective against hepatic parasites than dividing the same total dose into multiple administrations, which suggests that for elimination of hepatic parasites in vivo, peak Sb concentration is more important than total area-under-the-curve levels. Serum Sb declined with an initial half-life of 1 hr. Skin Sb levels (352 micrograms Sb/g 1 hr after 600 mg Sb/kg) were initially higher than liver levels (77 micrograms Sb/g) or splenic levels (156 micrograms Sb/g), but levels were comparable (7-24 micrograms Sb/g) in the three organs by 8 hr after dosing. The generally comparable levels of Sb in the skin and in the visceral organs support the present clinical practice of administering the same dosage of Sb for cutaneous and visceral leishmaniasis.     

Effect of gastrointestinal inflammation and age on the pharmacokinetics of oral microemulsion cyclosporin A in the first month after bone marrow transplantation

Cyclosporin A (CsA) absorption is highly variable in BMT patients. Neoral, a new microemulsion formulation of CsA, permits increased absorption with less variable pharmacokinetic parameters in non-BMT patients. We evaluated the pharmacokinetics of CsA after BMT in patients received microemulsion CsA. Two oral doses of 3mg/kg were given 48 h apart between 14 and 28 days after allogeneic BMT in 20 adults, and one dose in seven children, while subjects were receiving a continuous i.v. infusion of CsA. Whole blood samples were taken throughout the dosing interval to calculate the incremental CsA exposure using maximum concentration (Cmax), time to Cmax (tmax), concentration at 12 h after the dose (C12), the area under the concentration-time curve (AUC), and to establish inter- and intra-patient pharmacokinetic variability. Drug exposure was substantially lower in children than adults, with an AUC of 861+/-805 vs 2629+/-1487 micromg x h/l (P = 0.001), respectively, and absorption was delayed and diminished in both groups by comparison with solid organ recipients. Intra-patient variability in adults for AUC was high at 0.59+/-0.34, while inter-patient variability, measured as the coefficient of variation (c.v.), was 0.55 for the first and 0.54 for the second dose. In adults, gastrointestinal (GI) inflammation due to either mucositis or GVHD resulted in a higher AUC of 3077+/-1551 microg x h/l compared to 1795+/-973 microg x h/l (P = 0.02), and a similar trend was observed in children. AUC seemed little affected by the CsA formulation (liquid or capsule), or co-administration with liquids or food. Trough (12 h) CsA levels correlated poorly with incremental AUC. Sparse sample modeling of the AUC using two-point predictors taken at 2.5 and 5 h after dosing accurately approximated AUC in adults (r2 = 0.94), while 1.5 and 5 h was superior in children (r2 = 0.98). These data suggest that 12 h postdose trough measurements of CsA may not be the most appropriate way to evaluate CsA blood concentrations in order to establish therapeutic efficacy in BMT patients. Based on this study, the dose of microemulsion CsA should be adjusted based on recipient age, and the presence of GI inflammation secondary to mucositis or GVHD. These data would suggest that sparse sampling at time points earlier than the trough more accurately reflects the AUC and may correlate more closely with therapeutic efficacy early post-BMT.     

Efficacy of azithromycin versus systemic meglumine antimoniate (Glucantime) in the treatment of cutaneous leishmaniasis

Cutaneous leishmaniasis (CL) treatment is painful, and cosmetic results are often unsatisfying. Azithromycin has been reported to be effective in treatment of CL caused by Leishmania viannia braziliensis. The efficacy of azithromycin was compared with Glucantime in treatment of Old World leishmaniasis. Of 49 patients, 22 received 500 mg/day azithromycin for 5 days/month. Treatment cycles were repeated monthly to a maximum of 4 months; 27 patients received 60 mg/kg intramuscular meglumine antimoniate for 20 days. Both groups were followed up for 16 weeks. In the azithromycin group, 2 patients withdrew because of GI symptoms. The response rates of 20 patients (29 lesions) were as follows: full improvement, 10.3%; partial improvement, 27.6%; and 62.1%, no response. In the glucantime group with 27 patients (58 lesions), these rates were 34.4%, 13.8%, and 51.7%, respectively (P = 0.036). Azithromycin was determined to be not as effective as Glucantime in treatment of Old World CL.     

Randomized, double-blind study of stibogluconate plus human granulocyte macrophage colony-stimulating factor versus stibogluconate alone in the treatment of cutaneous Leishmaniasis.

The response to recombinant human granulocyte macrophage colony-stimulating factor (GM-CSF) in the treatment of cutaneous leishmaniasis was evaluated. Twenty patients with cutaneous leishmaniasis who had lesions for 60 days were enrolled in a double-blind placebo trial of GM-CSF with standard parenteral sodium stibogluconate (20 mg/kg-1/day-1) for 20 days. Ten patients were randomized to receive intralesionally injected GM-CSF (200 microgram) at enrollment and 1 week after, and 10 patients received saline as placebo. GM-CSF- and antimony-treated patients healed faster than patients who received antimony alone (49+/-32.8 vs. 110+/-61.6 days, P<.05). Seven of 10 patients were healed of their lesions before 40 days after therapy in the GM-CSF group, compared with only 1 of 10 patients in the placebo group (relative risk, 7; 95% confidence interval, 1.04-47.00). Thus, GM-CSF plus antimony significantly increased the chance of lesion healing in 40 days.     

Are there differences in clinical and laboratory parameters between children and adults with American visceral leishmaniasis?

A prospective study on 23 patients with American visceral leishmaniasis (VL), comparing clinical and laboratory parameters of 14 children (mean age of 3.85+/-3.39 years) to nine adults (27.4+/-10.90 years) was performed in S?o Luís, Maranh?o, Brazil, between August 2000 and July 2002. Data were collected at entrance (day 0), end of treatment, as well as 120 and 210 days after treatment using a protocol chart containing patient identification, clinical and laboratory data. N-Methylglucamine antimonate administered at the dose of 20mg/Sb5+/kg/day for 20-30 days was successfully used in all patients. Patients were followed for 1 year after treatment, and no relapses were observed. A prolonged duration of the disease, lymphadenopathy and bleeding predominated in adult patients, while hepatomegaly and skin-mucosal pallor were more frequent in children. Disease was longer and more severe in adults than in children. Although both groups exhibited a trend toward normalization of hematological and biochemical parameters, more children returned sooner to normal values than adults. Difference in clinical or laboratory parameters between children and adults did not indicate the need for different clinical or therapeutic approaches.     

Comparison of generic to branded pentavalent antimony for treatment of new world cutaneous leishmaniasis

The cost of generic pentavalent antimony (generic stibogluconate) is approximately one-sixth that of branded pentavalent antimony (stibogluconate in the form of Pentostam or meglumine antimoniate in the form of Glucantime. We compared generic stibogluconate to Pentostam and Glucantime for the treatment of cutaneous leishmaniasis patients in Bolivia and Colombia. For all 114 patients, the per-protocol cure rates were 83-91% and the intent-to-treat cure rates were 75-83%. The highest values were in the generic stibogluconate group. The incidence of pancreatic enzyme abnormalities was 48-88% and the incidence of liver enzyme abnormalities was 48-87%. The lowest incidences were in the generic stibogluconate group. The efficacy and tolerance of inexpensive generic stibogluconate appears comparable to branded formulations for the treatment of cutaneous leishmaniasis in these endemic regions.     

Recommendations for treating leishmaniasis with sodium stibogluconate (Pentostam) and review of pertinent clinical studies.

Pentavalent antimonial compounds have been the mainstay of the treatment of visceral, cutaneous, and mucosal leishmaniasis for approximately half a century. Pentostam (sodium stibogluconate) is the pentavalent antimonial compound available in the United States (through the Centers for Disease Control). As dosage regimens for treating leishmaniasis have evolved, the daily dose of antimony and the duration of therapy have been progressively increased to combat unresponsiveness to therapy. In the 1980s, the use of 20 mg/kg/day (instead of 10 mg/kg/day) of antimony was recommended, but only to a maximum daily dose of 850 mg. The authors have concluded on the basis of recent efficacy and toxicity data that this 850-mg restriction should be removed; the evidence to date, which is summarized here, suggests that a regimen of 20 mg/kg/day of pentavalent antimony, without an upper limit on the daily dose, is more efficacious and is not substantially more toxic than regimens with lower daily doses. We recommend treating all forms of leishmaniasis with a full 20 mg/kg/day of pentavalent antimony. We treat cutaneous leishmaniasis for 20 days and visceral and mucosal leishmaniasis for 28 days. Our judgment of cure is based on clinical criteria.     

Mucosal leishmaniasis ("espundia") responsive to low dose of N-methyl glucamine (Glucantime) in Rio de Janeiro, Brazil

Response to treatment with antimonial drugs varies considerably depending on the parasite strain involved, immune status of the patient and clinical form of the disease. Therapeutic regimens with this first line drug have been frequently modified both, in dose and duration of therapy. A regimen of 20 mg/kg/day of pentavalent antimony (Sb5+) during four weeks without an upper limit on the daily dose is currently recommended for mucosal disease ("espundia"). Side-effects with this dose are more marked in elderly patients, more commonly affected by this form of leishmaniasis. According to our experience, leishmaniasis in Rio de Janeiro responds well to antimony and, in cutaneous disease, high cure rates are obtained with 5 mg/kg/day of Sb5+ during 30 to 45-days. In this study a high rate of cure (91.4%) employing this dose was achieved in 36 patients with mild disease in this same geographic region. Side-effects were reduced and no antimony refractoriness was noted with subsequent use of larger dose in patients that failed to respond to initial schedule.     

Safety and effectiveness of amphotericin B deoxycholate for the treatment of visceral leishmaniasis in Uganda

Between September 2003 and April 2004, the supply of antimonial drugs to Amudat Hospital, in north-eastern Uganda, was interrupted and all cases of visceral leishmaniasis presenting at the hospital could only be treated with amphotericin B deoxycholate (AmB). This allowed the safety and effectiveness of the AmB to be evaluated, in comparison with an historical cohort of patients treated, at the same hospital, with meglumine antimoniate (Sb(V)). Demographic and clinical data were collected before and after treatment. Adverse effects were recorded passively in all the subjects, and actively, using a standardized questionnaire, in a sub-group of the patients given AmB. The in hospital case-fatality 'rates' were 4.8% [95% confidence interval (CI) = 2.4%-8.8%] among the 210 patients treated with AmB and 3.7% (CI = 1.4%-7.9%) among the 161 patients treated with Sb(V) (P>0.20). Adverse effects requiring treatment interruption were rare in both cohorts. Treatment failures (i.e. non-responses or relapses) were observed in 2.9% (CI = 1.2%-6.4%) of the patients treated with AmB and 1.2% (CI = 0.1%-4.4%) of the patients treated with Sb(V) (P>0.20). For the treatment of visceral leishmaniasis in Uganda, AmB therefore had a similar effectiveness and safety profile to that of meglumine antimoniate.