Cryptococcus neoformans is the most common systemic mycosis in patients with AIDS, and a leading cause of

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1 MAJOR ARTICLE HIV/AIDS Comparison of 2 Doses of Liposomal Amphotericin B and Conventional Amphotericin B Deoxycholate for Treatment of AIDS-Associated Acute Cryptococcal Meningitis: A Randomized, Double-Blind Clinical Trial of Efficacy and Safety Richard J. Hamill, 1 Jack D. Sobel, 4 Wafaa El-Sadr, 5 Philip C. Johnson, 2 John R. Graybill, 3 Kedarnath Javaly, 6 David E. Barker, 7 and the AmBisome Cryptococcal Meningitis Study Group a 1 Section of Infectious Diseases, Michael E. DeBakey Veterans Affairs Medical Center and Baylor College of Medicine, and 2 University of Texas Houston Medical School, Houston, and 3 University of Texas San Antonio Health Science Center, San Antonio, Texas; 4 Division of Infectious Diseases, Wayne State University, Detroit, Michigan; 5 Harlem Hospital Medical Center and 6 Bellevue Hospital and New York University, New York, New York; and 7 Cook County Hospital, Chicago, Illinois Background. It is generally acknowledged that amphotericin B is the most effective treatment for cryptococcal meningitis. However, administration of this drug is accompanied by substantial adverse effects. This double-blind study, performed before the routine availability of highly active antiretroviral therapy, was designed to compare the efficacy and safety of liposomal amphotericin B to conventional amphotericin deoxycholate in patients with acquired immunodeficiency syndrome (AIDS) and acute cryptococcal meningitis. Methods. Patients were randomized (ratio, 1:1:1) from multiple sites in the United States and Canada to receive either amphotericin B at 0.7 mg/kg/day (n p 87), liposomal amphotericin B at 3 mg/kg/day (n p 86), or liposomal amphotericin B at 6 mg/kg/day (n p 94). Results. Efficacy was similar among all 3 treatment groups. The overall incidence of infusion related reactions was significantly lower for both the 3 mg/kg/day and 6 mg/kg/day dosages of liposomal amphotericin B, compared with conventional amphotericin B (P!.001). Significantly fewer patients who received the 3 mg/kg/day dosage of liposomal amphotericin B developed nephrotoxicity, indicated by a doubling of the serum creatinine value, compared with recipients of conventional amphotericin B (P p.004). Overall mortality at 10 weeks was 11.6%, with no significant differences among the treatment groups. Conclusions. Liposomal amphotericin B provides an equally efficacious alternative to conventional amphotericin B deoxycholate in patients with AIDS and acute cryptococcal meningitis. Liposomal amphotericin B at a dosage of 3 mg/kg/day is accompanied by significantly fewer adverse effects. Cryptococcus neoformans is the most common systemic mycosis in patients with AIDS, and a leading cause of Received 20 November 2009; accepted 26 March 2010; electronically published 10 June Presented in part: the 39th Interscience Conference on Antimicrobial Agents and Chemotherapy, San Francisco, California, September 1999 (abstract 161). a Study group members are listed at the end of the text. Reprints or correspondence: Dr Richard J. Hamill, Section of Infectious Diseases (111G), Michael E. DeBakey VA Medical Center, 2002 Holcombe Blvd, Houston, TX (rhamill@bcm.edu). Clinical Infectious Diseases 2010; 51(2): by the Infectious Diseases Society of America. All rights reserved /2010/ $15.00 DOI: / mortality among these patients, especially in the developing world [1 4]. Before the introduction of highly active antiretroviral therapy (HAART), 5% 10% of patients with AIDS developed acute cryptococcal meningitis [1, 4]. Although the incidence of invasive cryptococcal disease has substantially decreased since the widespread use of HAART, it still occurs in populations with limited access to medical care, as well as those for whom antiretroviral therapy fails [5]. Treatment recommendations for AIDS-associated cryptococcal meningitis include a 2-week induction phase with a combination of higher-dose amphotericin B ( mg/ kg/day), with or without 5-flucytosine (5-FC), followed HIV/AIDS CID 2010:51 (15 July) 225

2 by consolidation with fluconazole [6, 7]. Using this regimen, studies in developed regions of the world have shown that mortality rates of 5% 11% and sterilization of cerebrospinal fluid (CSF) in 60% 75% are achieved at the end of therapy [6, 7]. Although it is considered the drug of choice for cryptococcal meningitis, amphotericin B therapy is complicated by substantial adverse effects. Previous treatment trials of other invasive mycoses have demonstrated that lipid preparations of amphotericin B can be given in substantially higher doses than amphotericin B deoxycholate (AmB) with considerably less nephrotoxicity [8 12] and fewer infusion-related reactions [9, 10, 12]. In addition, smaller studies have indicated that liposomal amphotericin B may represent a safer and therapeutically acceptable formulation for the treatment of cryptococcal infection in patients with AIDS [13 16]. However, for the treatment of acute cryptococcal meningitis, no large-scale, randomized, comparative trial of amphotericin B versus any lipid-based amphotericin B formulation has ever been performed (to our knowledge), nor do any data exist to suggest what the optimal dose of liposomal amphotericin B should be. Consequently, this study was designed to compare the safety, tolerability, and efficacy of 2 dosages of liposomal amphotericin B and conventional amphotericin B for patients with AIDS-associated acute cryptococcal meningitis. PATIENTS AND METHODS Enrollment and randomization. The study was conducted between June 1995 and April 1998 in accordance with The Declaration of Helsinki and Good Clinical Practice principals. Thirty-five institutions in the United States and Canada with extensive experience in the management of individuals with human immunodeficiency virus (HIV) infection participated. The protocol was reviewed by the institutional review boards of all the centers. Written informed consent was obtained from each patient their legal guardian. An independent data safety monitoring board reviewed blinded study results to ensure patients safety. Patients were eligible for enrollment if they had confirmed HIV infection and a cryptococcal meningitis diagnosis documented by CSF cryptococcal antigen testing or India ink examination or by a CSF culture that was positive for C. neoformans. Patients with a negative baseline CSF culture result after 4 weeks of incubation could remain in the study if there was clinical evidence of cryptococcal disease and laboratory confirmation (eg, positive CSF antigen titer results or histological evidence at a central nervous system site). Patients were excluded if they had already received a cumulative dose of 12.4 mg/kg amphotericin B, 115 mg/kg amphotericin B lipid complex, or mg of fluconazole. Patients were also excluded if they had another systemic fungal infection, a serum creatinine concentration greater than twice the upper limit of normal (1.2 mg/ dl), serum hepatic transaminase levels 110 times the upper limits of normal, were pregnant or lactating, were!1 month of age, or had a history of anaphylactic reaction to amphotericin B. Administration of study drugs. Patients were stratified at each site by primary or recurrent episode and then randomized in a 1:1:1 ratio to receive either AmB (Fungizone [Bristol- Myers Squibb]) at 0.7 mg/kg/day, liposomal amphotericin at 3.0 mg/kg/day (L-AmB 3; AmBisome [Astellas Pharma]), or liposomal amphotericin at 6.0 mg/kg/day (L-AmB 6) for an day induction. The targeted induction phase was 14 days of uninterrupted therapy; however, a minimum of 11 days was required, and treatment could have continued for up to 21 days of uninterrupted therapy if the patient had delayed improvement. Reduction or interruption of daily study drug administration was permitted for reasons such as toxicity or temporary lack of venous access. The AmB dose used in this study was chosen because it was found to be the most effective in randomized trials [6, 7]. The 3 mg/kg/day liposomal amphotericin B dosage was chosen because this regimen was welltolerated and effective in previous nonrandomized studies [15, 16]. The 6 mg/kg/day dosage was chosen on the basis of the hypothesis that a higher dose might provide a greater antifungal response without compromising safety and to potentially exploit the concentration-dependent killing properties of amphotericin B. At the end of induction, all patients were assigned to daily consolidation with fluconazole (400 mg) to complete 10 weeks of acute therapy. Patients were not given concomitant 5-flucytosine. Medications for management of infusion related reactions were allowed. All patients and study personnel were blinded to the treatment administered. The investigational pharmacist at each site determined study drug assignment by telephoning a central randomization center (Oxford Business Services; Yardley, PA). To maintain blinding, each infusion bag or bottle and tubing was modified to prevent the distinction between liposomal amphotericin B and amphotericin B, because the drugs differ in appearance. The volume of infusate was given over 2 4 h and was comparable regardless of treatment group. Intravenous saline loading was permitted. Evaluation. Clinical and laboratory evaluations were performed at baseline and twice weekly during induction and weekly or biweekly during consolidation. Assessments of neurologic signs and symptoms, evidence of increased intracranial pressure, clinical assessment of meningitis score (a scoring system consisting of a compilation of findings including headache, fever, level of consciousness, thought content, muscle strength, meningeal signs, and cranial nerve abnormalities) and Karnofsky performance status were performed at baseline, twice weekly during induction, and at least every other week during consolidation. Patients were monitored for infusion-related reactions dur- 226 CID 2010:51 (15 July) HIV/AIDS

3 Figure 1. Flow diagram for patients enrolled in cryptococcal meningitis treatment trial. AmB, amphotericin B deoxycholate; L-AmB 3, liposomal amphotericin at 3.0 mg/kg/day; L-AmB 6, liposomal amphotericin at 6.0 mg/kg/day. *Includes physician decision to remove, transfer, or discharge prematurely from the hospital and nonadherence to protocol. ing drug administration and for 1 h after completion of the infusion. Nephrotoxicity was defined as an increase in serum creatinine to a value greater than normal (1.2 mg/dl) and representing a value 150% greater than the upper limits of this baseline. Examination of CSF specimens was performed at the end of weeks 2 and 6. An additional lumbar puncture was performed at week 10 if the week 6 CSF culture result was positive. Opening pressure was to be measured on all patients. Interventions for the treatment of elevated intracranial pressure were recorded. Amphotericin B serum and CSF concentrations were determined at a central laboratory using a high-performance liquid chromatography procedure (quantitation limit, 0.10 mg/ L) [17]. Statistical analyses. Patients were grouped according to the following classification for analyses: (1) the modified intentto-treat population, which included all randomized patients who received at least 1 dose of study drug; (2) the mycological evaluable population, which included all randomized patients who underwent at least 1 follow-up CSF culture. Mycological evaluable patients who either completed study therapy or died during weeks 2 10 (days 14 85) of study were evaluable for protocol-defined therapeutic success. The primary efficacy end point was the incidence of mycological success (conversion of CSF culture results) at week 2 (14 4 days) among the mycological evaluable population. The secondary efficacy end points were (1) protocol-defined therapeutic success at week 10 among the mycological evaluable patients who completed study treatment or died during weeks 2 10 (days 14 85), and (2) survival at week 10 among the modified intent-to-treat population. Mycological success at week 10 was also recorded. A successful clinical outcome at 2 weeks was defined as no increase in the severity of the individual signs or symptoms of meningitis. Successful clinical outcome at 10 weeks was considered to be the absence of or clinically significant improvement in the signs and symptoms of men- HIV/AIDS CID 2010:51 (15 July) 227

4 Table 1. Baseline Demographic and Clinical Characteristics of Patients Who Received Liposomal Amphotericin B or Conventional Amphotericin B Deoxycholate Characteristic Liposomal amphotericin B group 3 mg/kg/day (n p 86) 6 mg/kg/day (n p 94) Amphotericin B group, 0.7 mg/ kg/day (n p 87) Age, mean years (range) 38.7 (22 61) 40.1 (21 68) 38.5 (10 59) Percentage of male subjects Primary disease 81 (94.3) 86 (91.5) 85 (97.7) Recurrent case 5 (5.8) 8 (8.5) 2 (2.3) Total CD4 cell count No. of patients with data Mean cells/ml (range) 49 (2 428) 51 (2 598) 42 (0 234) Baseline creatinine level, mean mg/dl Baseline hemoglobin concentration, mean g/dl No. of patients with positive CSF culture results Median CSF cryptococcal antigen titer (IQR) 1334 (138 10,031) 2590 ( ) 1345 ( ) Karnofsky score No. of patients with data Mean Opening pressure No. of patients with data Mean mm H 2 O NOTE. CSF, cerebrospinal fluid; IQR, interquartile range. ingitis, relative to the presenting meningitis score. Therapeutic success was defined as clinical success plus CSF culture sterilization at 10 weeks. The study was powered originally for 300 evaluable patients (100 in each arm). However, slow accrual following the widespread availability of HAART led to early termination of the trial, and power was recalculated on the basis of a sample size of 180 evaluable patients (60 in each arm). This sample size would allow for a 71% power to detect a difference of 20% in the mycological success rate between the combined liposomal amphotericin B group and the amphotericin B arm. Primary outcome was analyzed using a 2-sided 95% confidence interval (CI), constructed for the difference (combined liposomal amphotericin B amphotericin B) in the week 2 culture conversion rate. If the lower bound of the confidence interval was greater than 0.20, it was concluded that liposomal amphotericin B was not inferior to amphotericin B. If the lower bound was greater than 0, it was further concluded that liposomal amphotericin B was superior. If it was concluded that liposomal amphotericin B treatment (combined dose groups) was not inferior to amphotericin B, this same testing procedure was applied to individual liposomal amphotericin B dose groups (liposomal amphotericin B 3.0 mg/kg vs amphotericin B; liposomal amphotericin B 6.0 mg/kg vs amphotericin B). If the noninferiority claim could not be made for the liposomal amphotericin B combined-dose versus amphotericin B treatment, no further testing was done. The week 10 therapeutic success rate was analyzed by the same testing procedure as above. Survival at week 10 was determined by the Kaplan-Meier method. The modified intent-to-treat population was analyzed for safety and was assessed on the basis of the incidence of adverse events, nephrotoxicity, and hepatotoxicity. Incidences of adverse events and other safety variables were tabulated by treatment group and compared using the Fisher exact test. Kaplan- Meier plots were used in nephrotoxicity evaluations. RESULTS Patients. A total of 275 patients from 35 institutions were enrolled during the period 29 June 1995 through 22 April Five patients were ineligible at baseline or did not receive drug (1 refused to sign consent, 1 withdrew consent, 1 died before receiving the first dose, 1 was transferred to another hospital, and 1 patient had received a misdiagnosis). Three patients were inadvertently randomized twice but did not receive drug under the misrandomized numbers. Of the 267 patients included in the modified intent-to-treat analysis, 86 received L-AmB 3, 94 received L-AmB 6, and 87 received AmB (Figure 1). Demographic characteristics and baseline laboratory values, CD4 lymphocyte counts, and clinical signs and symptoms of cryptococcal disease did not differ significantly among the 3 groups 228 CID 2010:51 (15 July) HIV/AIDS

5 Table 2. Efficacy of Liposomal Amphotericin B and Conventional Amphotericin B Deoxycholate (AmB) Parameter Mycological success b No. (%) of patients, by regimen Treatment difference, % (95% CI) a L-AmB 3 L-AmB 6) AmB L-AmB 3 vs AmB L-AmB 6 vs AmB Week 2 35 (58.3) 36 (48) 29 (47.5) 10.8 ( 6.9 to 28.5) 0.5 ( 16.4 to 17.3) Week (60) 53 (70.7) 48 (78.7) Therapeutic success: c week (67.5) 42 (73.7) 40 (75.5) 8.0 ( 26.5 to 10.6) 1.8 ( 18.1 to 14.5) Clinical success Week 2 d 48 (65.8) 64 (75.3) 50 (65.8) Week 10 e 31 (70.5) 43 (72.9) 44 (81.5) Survival: f week (86) 85 (90.4) 77 (88.5) NOTE. CI, confidence interval; L-AmB 3, liposomal amphotericin at 3.0 mg/kg/day; L-AmB 6, liposomal amphotericin at 6.0 mg/kg/day. a Treatment difference for 1 end point for incidence of mycological success at week 2. b All randomized patients who received 1 dose of study drug, had a positive baseline culture result, and underwent 1 follow-up culture. c All randomized patients who received 1 dose of study drug, had a positive baseline culture result, and underwent 1 follow-up culture (ie, mycological evaluable patients) and who completed therapy or died during weeks d All randomized patients who received 1 dose of study drug and had a positive baseline culture result. e All randomized patients who received 1 dose of study drug and had a positive baseline culture result who completed therapy or died during weeks f Among the modified intent-to-treat population, the Kaplan-Meier estimate of patient survival was 83.6% (95% CI, 75.7% 91.6%) for the combined liposomal amphotericin B groups and 87% (95% CI, 79.5% 95.6%) for the amphotericin B group. (Table 1). The median number of days receiving the study drug was 14 days and the median number of infusions of study drug per patient was 13 in all 3 groups. Mycological outcome. As shown in Table 2 for the primary efficacy end point, CSF culture results were negative at 2 weeks in 47.5% of patients who received AmB, in 58.3% of those who received L-AmB 3, and in 48.0% of those who received L-AMB 6. None of these differences among the groups were statistically significant (treatment difference for L-AmB 3 vs AmB, 10.8% [95% CI, 6.9% to 28.5%]; and treatment difference for L- AmB 6 vs AmB, 0.5% [95% CI, 16.4% to 17.3%]). The lower bounds of the 95% CIs for the treatment differences (liposomal amphotericin B amphotericin B) were all greater than 20% but not greater than 0. Consequently, liposomal amphotericin B (combined, 3 and 6 mg/kg) was at least as effective as, but not superior to, AmB with regard to mycological success at week 2. At 10 weeks, 78.7% of patients who had received AmB had negative CSF culture results, as did 60% of patients who had received L-AmB 3 and 70.7% of those who received L- AmB 6 (Table 2). Clinical response. Clinical responses at 2 weeks, as determined by improvement in the severity of the individual signs and symptoms of meningitis occurred in 65.8% of patients who received AmB, compared with 65.8% of patients who received L-AmB 3 and 75.3% who receive L-AmB 6 (Table 2). Clinical success at 10 weeks was defined as absence of fever and meningeal signs, reduction of headache severity by at least one grade, and stabilization or improvement in the other clinical parameters. Success was achieved in 81.5% of patients who received AmB, 70.5% of those who received L-AmB 3 and Table 3. Incidence of Infusion-Related Reactions among Recipients of Liposomal Amphotericin B and Conventional Amphotericin B Deoxycholate (AmB) Infusion-related reaction No. (%) of patients, by regimen L-AmB 3 (n p 86) L-AmB 6 (n p 94) AmB (n p 87) L-AmB 3 vs AmB P a L-AmB 6 vs AmB Increase in temperature 1.0 C 6 (7) 8 (8.5) 24 (27.6)!.001!.001 Chills and/or rigors 5 (5.8) 8 (8.5) 42 (48.3)!.001!.001 Nausea 11 (12.8) 13 (13.8) 18 (20.7) Vomiting 14 (16.3) 13 (13.8) 16 (18.4) Respiratory system (any adverse event) 0 (0) 1 (1.1) 8 (9.2) Overall 27 (31.4) 35 (37.2) 58 (66.7)!.001!.001 NOTE. AE, adverse event; L-AmB 3, liposomal amphotericin at 3.0 mg/kg/day; L-AmB 6, liposomal amphotericin at 6.0 mg/kg/day. a Determined using the Fisher exact test. HIV/AIDS CID 2010:51 (15 July) 229

6 Table 4. Adverse Events among Recipients of Liposomal Amphotericin B and Conventional Amphotericin B Deoxycholate (AmB) Adverse event No. (%) of patients, by regimen L-AmB 3 L-AmB 6 AmB L-AmB 3 vs AmB P L-AmB 6 vs AmB Creatinine level of 2.0 times baseline and 11.2 mg/dl 12 (14.9) 20 (21.3) 29 (33.3) Serum potassium level,!3.0 mmol/l 8 (9.3) 33 (35.1) 26 (29.9) Hemoglobin concentration, 8 g/dl 20 (23.3) 39 (41.5) 38 (43.7) NOTE. L-AmB 3, liposomal amphotericin at 3.0 mg/kg/day; L-AmB 6, liposomal amphotericin at 6.0 mg/kg/day. 72.9% of those who received L-AmB 6 (Table 2). Mean meningitis scores decreased from baseline to a similar extent in all groups as did decreases in opening pressures and median CSF cryptococcal antigen titers (data not shown). Safety and tolerance. The incidence of infusion-related reactions, as well as the individual frequencies of fever, chills or rigors and respiratory events, were significantly lower for patients administered either dose of liposomal amphotericin B compared with AmB (Table 3). Significant anemia, as indicated by a hemoglobin concentration 8 g/dl, occurred less frequently in the L-AmB 3 arm (Table 4). Dose reductions for any toxicity were required in 4.7% of L-AmB 3 recipients, 13.8% of L-AmB 6 recipients, and 27.6% of AmB recipients. However, discontinuation of study drugs for any adverse event was low for all 3 arms (3.5%, 2.1%, and 4.6%, respectively). Nephrotoxicity. Significantly fewer patients who received L-AmB 3 developed nephrotoxicity, as indicated by a doubling of the serum creatinine level (Pp.04) (Table 4); the difference for L-AmB 6 was not significant, although there was a trend towards less nephrotoxicity (P p 0.066). Significantly fewer patients in the L-AmB 3 arm developed serum potassium values!3 mmol/l than in the other 2 arms (Table 4). Mortality. Thirty-one patients (11.6%) died during the study: 12 (13.9%) in the L-AmB 3 arm, 9 (9.5%) in the L- AMB 6 arm, and 10 (11.5%) in the AmB arm. Of these deaths, 10 could be directly attributed to acute or chronic cryptococcal disease, with no differences among the treatments. Amphotericin B concentrations. Substantially higher mean serum concentrations were obtained at weeks 1 and 2 with both doses of liposomal amphotericin B (Table 5). Even by week 10, some patients in all 3 groups still had measurable serum levels of amphotericin B. Only 6 patients had levels of amphotericin B that could be detected in CSF samples at week 2. DISCUSSION This randomized, double-blind, multicenter trial comparing 2 doses of liposomal amphotericin B with AmB for therapy of acute cryptococcal meningitis in patients with AIDS demonstrated that all 3 regimens had similar success. In addition, the mycological success rates of 50% 65% at week 2 and 60% 70% at week 10 are consistent with those reported in earlier trials [6, 7, 13, 16]. In smaller studies, use of amphotericin B lipid complex also showed similar clinical success and reduced toxicity [18, 19]. Although it was previously shown that liposomal amphotericin B, 4 mg/kg/day, was more fungicidal than amphotericin B, 0.7 mg/kg/day [13], the results of our study indicate that dosages of liposomal amphotericin B 13 mg/kg/day provide no Table 5. Serum and Cerebrospinal Fluid (CSF) Concentrations of Amphotericin B Characteristic No. of samples a Regimen L-AmB 3 L-AmB 6 AmB Mean mg/l SD No. of samples a Mean mg/l SD No. of samples a Mean mg/l SD Serum concentration Baseline Week Week Week 9/ CSF concentration at week NOTE. AmB, amphotericin B deoxycholate; L-AmB 3, liposomal amphotericin at 3.0 mg/kg/day; L-AmB 6, liposomal amphotericin at 6.0 mg/kg/day. a No. of samples with measurable amphotericin B levels at the indicated time. 230 CID 2010:51 (15 July) HIV/AIDS

7 substantial additional benefit. Similar conclusions regarding the lack of any additional benefit of higher dosages of liposomal amphotericin B were reached in previous studies in different diseases states [20, 21]. Although it is generally accepted that amphotericin B displays concentration-dependent killing, higher serum levels of liposomal amphotericin B did not translate into significant improvements in clinical outcome. It is likely that the fungal burden and lack of effective immune response in these patients are more important determining factors than microbial killing. A recent small study that utilized higher doses of amphotericin B and demonstrated accelerated quantitative declines in CSF fungal counts did not show an improvement in clinical benefit [22]. This study also supports the findings from previous randomized trials that liposomal amphotericin B has significantly lower infusion-related toxicity and nephrotoxicity than AmB [9,11 14, 23]. Measurable CSF levels of amphotericin B were present as long as 8 weeks after discontinuation of liposomal amphotericin B; however, very few patients had levels that could be determined. In an experimental animal model of Candida albicans central nervous system infection, liposomal amphotericin B and AmB cleared the brain of C. albicans significantly better than either amphotericin B colloidal dispersion or amphotericin B lipid complex [24]. Several limitations of this study are evident, including the failure to enroll the originally determined sample size because of decreased accrual following the widespread use of HAART. In addition, because this study was carried out in the pre- HAART era, the potential clinical benefits of the early administration of HAART to individuals with this opportunistic infection were not realized [25]. Furthermore, the results in the present study were achieved despite the fact that no provisions were made for the addition of 5-FC. In a previous trial, 5-FC had minimal impact on the outcome of induction therapy; however, the absence of 5-FC in the induction regimen was significantly related to late relapse [7, 26]. On the other hand, Brouwer et al [27] demonstrated that the combination was more rapidly fungicidal compared to amphotericin B alone. There are scant reports concerning the use of lipid formulations of amphotericin B combined with 5-FC, but clinical experience suggests that combination is effective [6]. Future research should investigate the efficacy of combinations of liposomal amphotericin B with 5-FC or fluconazole [28]. Finally, it would be difficult to extrapolate the results of this study to regions of the world where economic barriers preclude the use of liposomal amphotericin B. The need to discontinue AmB therapy because of treatmentrelated adverse events was low (3.5%) and no different than the rates of discontinuation for L-AmB 3 (2.1%) or L-AmB 6 (4.6%). This discontinuation rate for AmB is similar to those observed in other comparative trials [7], even those using higher dosages in countries with limited resources [22]. Therefore, AmB should still be considered the drug of choice for treatment of AIDS-associated cryptococcal meningitis. However, in those individuals who have preexisting renal disease or intolerable infusion-related toxicity, liposomal amphotericin B at doses of either 3 or 6 mg/kg/day appears to provide an equally efficacious alternative to AmB. Given the lower frequency of adverse events, L-AmB 3 should be preferred, as has been recently recommended [6]. MEMBERS OF THE AMBISOME CRYPTOCOCCUS MENINGITIS STUDY GROUP In addition to the authors, the following individuals and institutions made significant contributions to this study: Donald Buell and Boyd Roloff (Astellas Pharma; Deerfield, IL); Chris E. Lacke and Edward A. Graviss (Baylor College of Medicine; Houston, TX); John R. Black (Methodist Hospital of Indiana; Indianapolis); Dennis Cunniff (University of Medicine & Dentistry of New Jersey; Newark); Brian Currie (Montefiore Medical Center; New York, NY); S. Reeves Dill (University of South Alabama; Mobile); Robert H. Eng (Veterans Affairs Medical Center; East Orange, NJ); W. Jeffrey Fessel (Kaiser Permanente Medical Center; Los Angeles, CA); Stephen Follansbee (Davies Medical Center; San Francisco, CA); Mitchell Goldman (Indiana University Medical Center; Indianapolis); David W. Haas (Vanderbilt University; Nashville, TN); Edward Johnson (St Michael s Medical Center; Newark, NJ); Meera Kashkari (Bellevue Hospital; New York, NY); Thomas Kerkering (Medical College of Virginia; Richmond); Oscar Klein (St Vincent s Hospital and Medical Center; New York); Nancy Klimas (Miami Veterans Affairs Medical Center; Miami, FL); Susan Koletar (Ohio State University; Columbus); Jeffrey L., Lennox (Ponce de Leon Center; Atlanta, GA); Joseph Marzouk (Summit Hospital; Oakland, CA); Michael Mullen (Cabrini Medical Center; New York); George Pankey (Oschner Hospital Foundation; New Orleans, LA); James E. Peacock Jr (Wake Forest University School of Medicine; Winston-Salem, NC); Peter Phillips (St Paul s Hospital; Vancouver, BC); Corinna Quan (The Wellesley Hospital; Toronto, Ontario, Canada); John Stansell (San Francisco General Hospital (San Francisco, CA); David R. Stone (Lemuel Shattuck Hospital; Jamaica Plain, MA); Edward Stool (Park Plaza Hospital; Houston); Byungse Suh (Temple University; Philadelphia, PA); Steven Szebenyi (Albany Medical College; Albany, NY); Carmelita Tuazon (The George Washington University Medical Center; Washington, DC). Acknowledgments Financial support. Astellas Pharma and, in part, the Department of Veterans Affairs and the National Center for Research Resources, General Clinical Research Center (contract M01-RR02558). Manuscript preparation. Astellas Pharma provided assistance with study design and execution, as well as statistical analyses. HIV/AIDS CID 2010:51 (15 July) 231

8 Potential conflicts of interest. J.D.S. has received research funding from Merck Pharmaceuticals and has been on the speakers bureaus for Pfizer and Astellas Pharma. J.R.G. serves as a research consultant for Schering-Plough. D.E.B. has received research funding from Pfizer, Merck, Tibotec, and Virco. All other authors: no conflicts. References 1. Park BJ, Wannemuehler KA, Marston BJ, Govender N, Pappas PG, Chiller TM. Estimation of the current global burden of cryptococcal meningitis among persons living with HIV/AIDS. AIDS 2009; 23: French N, Gray K, Watera C, et al. Cryptococcal infection in a cohort of HIV-1 infected Ugandan adults. AIDS 2002; 16: Békondi C, Bernede C, Passone N, et al. Primary and opportunistic pathogens associated with meningitis in adults in Bangui, Central African Republic, in relation to human immunodeficiency virus serostatus. Int J Infect Dis 2006; 10: Chayakulkeeree M, Perfect JR. Cryptococcosis. 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