Prophylactic use of itraconazole for the prevention of invasive pulmonary aspergillosis in high risk neutropenic patients

Pharmacokinetic and clinical comparison of super-bioavailable itraconazole and conventional itraconazole at different dosing in dermatophytosis

Background

Due to changing face of dermatophytosis in India, many dermatologists practice different dosing patterns of itraconazole (ITZ). Recently, a new form of ITZ, super-bioavailable ITZ (SBITZ), has been commercialized to overcome the pharmacokinetic challenges of conventional ITZ (CITZ). Serum and sebum concentration of ITZ plays an important role in the management of dermatophytosis. Hence, the current study compares the rate and extent of serum and sebum concentration of SBITZ and CITZ at different dosing to determine their efficacy and safety in patients with dermatophytosis.

Methods

This was an open-label, randomized, four-arm study including 40 adult patients diagnosed with glabrous tinea who were randomized equally into four groups to receive either CITZ-100-BD or CITZ-200-OD (2×100 mg capsules) or SBITZ-130-OD or SBITZ-100-OD (2×SBITZ-50 mg capsules) for 4 weeks. Serum and sebum samples were analysed at different time intervals along with clinical efficacy and safety.

Results

For serum concentration, on day 28, the arithmetic mean and standard deviation (SD) for CITZ-100-BD, CITZ-200-OD, SB-130-OD and SB100-OD were 1262±233.5 ng/mL, 1704±261.6 ng/mL, 1770±268.9 ng/mL and 1520±231.7 ng/mL, respectively, which was statistically significant for OD dosing of ITZ/SBITZ over CITZ-100-BD. Similarly, for sebum concentration, the arithmetic mean and SD for CITZ-100-BD, CITZ-200-OD, SB-130-OD and SB-100-OD were 1042±163.45 ng/mg, 1423±192.46 ng/mg, 1534±227.55 ng/mg and 1107±182.35 ng/mg, respectively, which was statistically significant for SB-130-OD and CITZ-200-OD over CITZ-100-BD and SBITZ-100-OD dosing. No significant difference was noted between SBITZ-130 and CITZ-200 (p=0.25). Only two patients achieved complete cure in the SBITZ-130 group, whereas no patients achieved the same in other groups (p=0.47). All the dosages were very well tolerated with only 12 adverse events reported by ten patients in all groups.

Conclusion

All formulations achieved desired serum and sebum concentrations required for efficacy in dermatophytosis, but SB 130 mg OD and CITZ 200 mg OD were statistically significant than other ITZ doses in achieving sebum concentration. Additionally, SBITZ 130 mg OD was bioequivalent to CITZ 200 mg OD and achieved similar results to those of CITZ 200 mg OD but at 35% lower drug concentrations.

Modeling Invasive Aspergillosis: How Close Are Predicted Antifungal Targets?

Animal model systems are a critical component of the process of discovery and development of new antifungal agents for treatment and prevention of invasive aspergillosis. The persistently neutropenic rabbit model of invasive pulmonary aspergillosis (IPA) has been a highly predictive system in identifying new antifungal agents for treatment and prevention of this frequently lethal infection. Since its initial development, the persistently neutropenic rabbit model of IPA has established a strong preclinical foundation for dosages, drug disposition, pharmacokinetics, safety, tolerability, and efficacy for deoxycholate amphotericin B, liposomal amphotericin B, amphotericin B lipid complex, amphotericin B colloidal dispersion, caspofungin, micafungin, anidulafungin, voriconazole, posaconazole, isavuconazole, and ibrexafungerp in treatment of patients with invasive aspergillosis. The findings of combination therapy with a mould-active triazole and an echinocandin in this rabbit model also predicted the outcome of the clinical trial for voriconazole plus anidulafungin for treatment of IPA. The plasma pharmacokinetic parameters and tissue disposition for most antifungal agents approximate those of humans in persistently neutropenic rabbits. Safety, particularly nephrotoxicity, has also been highly predictive in the rabbit model, as exemplified by the differential glomerular filtration rates observed in animals treated with deoxycholate amphotericin B, liposomal amphotericin B, amphotericin B lipid complex, and amphotericin B colloidal dispersion. A panel of validated outcome variables measures therapeutic outcome in the rabbit model: residual fungal burden, markers of organism-mediated pulmonary injury (lung weights and infarct scores), survival, and serum biomarkers. In selected antifungal studies, thoracic computerized tomography (CT) is also used with diagnostic imaging algorithms to measure therapeutic response of pulmonary infiltrates, which exhibit characteristic radiographic patterns, including nodules and halo signs. Further strengthening the predictive properties of the model, therapeutic response to successfully developed antifungal agents for treatment of IPA has been demonstrated over the past two decades by biomarkers of serum galactomannan and (1→3)-β-D-glucan with patterns of resolution, that closely mirror those documented responses in patients with IPA. The decision to move from laboratory to clinical trials should be predicated upon a portfolio of complementary and mutually validating preclinical laboratory animal models studies. Other model systems, including those in mice, rats, and guinea pigs, are also valuable tools in developing clinical protocols. Meticulous preclinical investigation of a candidate antifungal compound in a robust series of complementary laboratory animal models will optimize study design, de-risk clinical trials, and ensure tangible benefit to our most vulnerable immunocompromised patients with invasive aspergillosis.

Open-Label Crossover Oral Bioequivalence Pharmacokinetics Comparison for a 3-Day Loading Dose Regimen and 15-Day Steady-State Administration of SUBA-Itraconazole and Conventional Itraconazole Capsules in Healthy Adults

Super bioavailability (SUBA) itraconazole (S-ITZ), which releases drug in the duodenum, and conventional itraconazole (C-ITZ), which releases drug in the stomach, were compared in two pharmacokinetic (PK) studies: a 3-day loading dose study and a 15-day steady-state administration study. These were crossover oral bioequivalence studies performed under fed conditions in healthy adult volunteers. In the loading dose study, C-ITZ (two doses of 100 mg each) and S-ITZ (two doses of 65 mg each) were administered three times daily for 3 days and once on day 4 (n = 15). For the steady-state administration study, C-ITZ (two doses of 100 mg each) and S-ITZ (two doses of 65 mg each) were administered twice daily for 14 days and a last dose was administered 30 min after a meal on day 15 (n = 16). Blood samples collected throughout both studies were analyzed for ITZ and hydroxy-ITZ (OH-ITZ) levels. Least-squares geometric means were used to compare the maximum peak concentration of drug after administration at steady state prior to administration of the subsequent dose (C _{max_ss}), the minimum drug level after administration prior to the subsequent dose (C _trough), and the area under the curve over the dosing interval (AUC_tau) of each formulation. The ratios of itraconazole (ITZ) and OH-ITZ for S-ITZ to C-ITZ were between 107% and 118% in both studies for C _{max_ss}, C _trough, and AUC_tau, which were within the U.S. FDA-required bioequivalence range of 80% to 125%. At the end of the steady-state administration study, 13 of 16 volunteers obtained higher mean ITZ blood C _trough levels of >1,000 ng/ml when they were administered S-ITZ (81%) than when they were administered C-ITZ (44%). The study drugs were well tolerated in both studies, with similar adverse events (AEs). All treatment-emergent AEs resolved after study completion. One volunteer receiving C-ITZ discontinued due to a treatment-unrelated AE in the steady-state administration study. No serious AEs were reported. Total, trough, and peak ITZ and OH-ITZ exposures were similar between the two formulations. Therefore, SUBA-ITZ, which has 35% less drug than C-ITZ, was bioequivalent to C-ITZ in healthy adult volunteers and exhibited a safety profile similar to that of C-ITZ.

Plasma Concentration of Itraconazole in Patients With Hematologic Malignancies Treated With Itraconazole Oral Solution

BACKGROUND

The prophylactic administration of itraconazole (ITCZ) is effective for preventing mycotic infections during chemotherapy in patients with hematologic malignancies. However, fungal infections can occur when the ITCZ does not reach an effective concentration.

METHODS

We conducted a prospective study to monitor the plasma concentration of ITCZ and hydroxyl-ITCZ (OH-ITCZ) weekly and to verify whether the day 3 plasma concentration of ITCZ could predict the subsequent acquisition of an effective plasma concentration.

RESULTS

A total of 39 patients who underwent 66 courses of chemotherapy were assessed in this study. An effective plasma concentration was achieved on day 7 in 34 of 63 patients (54%) and on day 14 in 35 of 59 patients (59%). A univariate analysis revealed that age, type of chemotherapy, and the body surface area were significantly associated with a high plasma concentration of ITCZ + OH-ITCZ. A linear regression analysis extracted the body surface area and the type of chemotherapy as significant factors. An receiver operating characteristic curve analysis revealed a day 3 plasma ITCZ + OH-ITCZ concentration of >656 ng/mL led to a plasma concentration that exceeded the minimum effective level on day 7; the sensitivity and specificity were 62% and 93%, respectively.

CONCLUSIONS

This study showed that the measurement of the day 3 plasma concentration could lead to a better outcome in patients receiving chemotherapy for hematologic malignancies.

Primary prophylaxis of invasive fungal infections in patients with hematologic malignancies. Recommendations of the Infectious Diseases Working Party of the German Society for Haematology and Oncology

There is no widely accepted standard for antifungal prophylaxis in patients with hematologic malignancies. The Infectious Diseases Working Party of the German Society for Haematology and Oncology assigned a committee of hematologists and infectious disease specialists to develop recommendations. Literature data bases were systematically searched for clinical trials on antifungal prophylaxis. The studies identified were shared within the committee. Data were extracted by two of the authors (OAC and MSi). The consensus process was conducted by email communication. Finally, a review committee discussed the proposed recommendations. After consensus was established the recommendations were finalized. A total of 86 trials were identified including 16,922 patients. Only a few trials yielded significant differences in efficacy. Fluconazole 400 mg/d improved the incidence rates of invasive fungal infections and attributable mortality in allogeneic stem cell recipients. Posaconazole 600 mg/d reduced the incidence of IFI and attributable mortality in allogeneic stem cell recipients with severe graft versus host disease, and in patients with acute myelogenous leukemia or myelodysplastic syndrome additionally reduced overall mortality. Aerosolized liposomal amphotericin B reduced the incidence rate of invasive pulmonary aspergillosis. Posaconazole 600 mg/d is recommended in patients with acute myelogenous leukemia/myelodysplastic syndrome or undergoing allogeneic stem cell recipients with graft versus host disease for the prevention of invasive fungal infections and attributable mortality (Level A I). Fluconazole 400 mg/d is recommended in allogeneic stem cell recipients until development of graft versus host disease only (Level A I). Aerosolized liposomal amphotericin B is recommended during prolonged neutropenia (Level B II).

Antifungal Prophylaxis in Cancer Patients After Chemotherapy or Hematopoietic Stem-Cell Transplantation: Systematic Review and Meta-Analysis

Purpose

To evaluate the effect of antifungal prophylaxis on all-cause mortality as primary outcome, invasive fungal infections (IFIs), and adverse events. Many studies have evaluated the role of antifungal prophylaxis in cancer patients, with inconsistent conclusions.

Methods

We performed a systematic review and meta-analysis of randomized, controlled trials comparing systemic antifungals with placebo, no intervention, or other antifungal agents for prophylaxis in cancer patients after chemotherapy. The Cochrane Library, MEDLINE, conference proceedings, and references were searched. Two reviewers independently appraised the quality of trials and extracted data.

Results

Sixty-four trials met inclusion criteria. Antifungal prophylaxis decreased all-cause mortality significantly at end of follow-up compared with placebo, no treatment, or nonsystemic antifungals (relative risk [RR], 0.84; 95% CI, 0.74 to 0.95). In allogeneic hematopoietic stem-cell transplantation (HSCT) recipients, prophylaxis reduced all-cause mortality (RR, 0.62; 95% CI, 0.45 to 0.85), fungal-related mortality, and documented IFI. In acute leukemia patients, there was a significant reduction in fungal-related mortality and documented IFI, whereas the difference in mortality was only borderline significant (RR, 0.88; 95% CI, 0.74 to 1.06). Prophylaxis with itraconazole suspension reduced documented IFI when compared with fluconazole, with no difference in survival, and at the cost of more adverse events. On the basis of two studies, posaconazole prophylaxis reduced all-cause mortality (RR, 0.74; 95% CI, 0.56 to 0.98), fungal-related mortality, and IFI when compared with fluconazole.

Conclusion

Antifungal prophylaxis decreases all-cause mortality significantly in patients after chemotherapy. Antifungal prophylaxis should be administered to patients undergoing allogeneic HSCT, and should probably be administered to high-risk acute leukemia patients.

Itraconazole-related increased vincristine neurotoxicity: case report and review of literature

Itraconazole is particularly attractive in fungal prophylaxis for cancer patients due to its broad spectrum, including Candida and Aspergillus. It is generally well tolerated. However, its efficacy in preventing invasive aspergillosis could not be demonstrated. A 3-year-old boy diagnosed with acute lymphoblastic leukemia received induction chemotherapy. On day 14, itraconazole solution at a dose of 5 mg/kg was begun. Ten days after itraconazole was started, he developed paralytic ileus, neurogenic bladder, mild left ptosis, and absence of deep reflexes, with severe paralysis of the lower extremities and mild weakness of the upper extremities. Itraconazole withdrawal was followed by rapid improvement, with neurologic examination returning to normal within 6 weeks. Nineteen cases of unusual enhanced vincristine neurotoxicity related to itraconazole have been reported in children. Although the manifestations are the same as those usually associated with the use of vincristine, in these cases the severity appears remarkable. The authors suggest that in the absence of any proven benefit of itraconazole prophylaxis, and given the interaction of this drug with vincristine leading to severe and even potentially fatal toxicities, the combination use of these drugs should be avoided.

A pilot study of targeted itraconazole prophylaxis in patients with graft-versus-host disease at high risk of invasive mould infections following allogeneic stem cell transplantation

Patients with severe graft-versus-host disease (GVHD) requiring intensive immunosuppression are at high risk of invasive mould infections (IMI). Prophylaxis with an active, oral antifungal agents with reliable absorption in this context is desirable. A total of 44 patients at high risk of post-engraftment IMI received itraconazole solution 2.5 mg/kg b.d. as prophylaxis. Two of the first nine patients, in whom bioavailability was compromised due to significant vomiting and/or diarrhoea, died of probable or proven invasive aspergillus. None of the subsequent 35 patients, some of whom had severe gut GVHD and who received liposomal amphotericin B prophylaxis until itraconazole was reliably tolerated and absorbed, developed IMI. The overall incidence of IMI was substantially lower than in historical controls. Itraconazole was generally well tolerated, with five patients (11%) ceasing the drug due to intolerance or disturbed liver function. Targeted prophylaxis with oral or parenteral antifungal agents in high-risk allograft recipients appears to be effective in reducing the incidence of IMI.

Itraconazole antagonizes store-operated influx of calcium into chemoattractant-activated human neutrophils

We have investigated the effects of itraconazole (0.1-10 micro m), an antimycotic which is often used prophylactically in primary and secondary immunodeficiency disorders, including chronic granulomatous disease, on mobilization of Ca(2+) and restoration of Ca(2+) homeostasis following activation of neutrophils with FMLP or PAF. Transmembrane fluxes of Ca(2+), as well as cytosolic concentrations of the cation were measured using a combination of spectrofluorimetric and radiometric procedures. The abruptly occurring increases in cytosolic Ca(2+) following activation of the cells with either FMLP (1 micro m) or PAF (200 nm) were unaffected by itraconazole. However, the subsequent store-operated influx of the cation was attenuated by itraconazole at concentrations of 0.25 micro m and higher. The itraconazole-mediated inhibition of uptake of Ca(2+) was not associated with detectable alterations in the intracellular concentrations of cyclic AMP, ATP or inositol triphosphate, and appeared to be compatible with antagonism of store-operated Ca(2+) channels. Although a secondary property, this anti-inflammatory activity of itraconazole, if operative in vivo, may be beneficial in conditions associated with dysregulation of neutrophil Ca(2+) handling such as CGD.

Itraconazole to prevent fungal infections in chronic granulomatous disease

BACKGROUND

Chronic granulomatous disease is a rare disorder in which the phagocytes fail to produce hydrogen peroxide. The patients are predisposed to bacterial and fungal infections. Prophylactic antibiotics and interferon gamma have reduced bacterial infections, but there is also the danger of life-threatening fungal infections. We assessed the efficacy of itraconazole as prophylaxis against serious fungal infections in chronic granulomatous disease.

METHODS

Thirty-nine patients at least 5 years old (6 female and 33 male; mean age, 14.9 years) were enrolled in a randomized, double-blind, placebo-controlled study. After the initially assigned treatment, each patient alternated between itraconazole and placebo annually. Patients 13 years of age or older and all patients weighing at least 50 kg received a single dose of 200 mg of itraconazole per day; those less than 13 years old or weighing less than 50 kg received a single dose of 100 mg per day. The primary end point was severe fungal infection, as determined by histologic results or culture.

RESULTS

One patient (who had not been compliant with the treatment) had a serious fungal infection while receiving itraconazole, as compared with seven who had a serious fungal infection while receiving placebo (P=0.10). No patient receiving itraconazole but five patients receiving placebo had a superficial fungal infection. No serious toxic effects were noted, although one patient had a rash and another had elevated results on liver-function tests; both of these effects resolved with the discontinuation of itraconazole.

CONCLUSIONS

Itraconazole prophylaxis appears to be an effective and well-tolerated treatment that reduces the frequency of fungal infections in chronic granulomatous disease, but monitoring for long-term toxic effects is warranted.

Evidence-based assessment of primary antifungal prophylaxis in patients with hematologic malignancies

Invasive fungal infection is an increasing source of morbidity and mortality in patients with hematologic malignancies, particularly those with prolonged and severe neutropenia (absolute white blood cell count < 100/microL). Early diagnosis of invasive fungal infection is difficult, suggesting that antifungal prophylaxis could be the best approach for neutropenic patients undergoing intensive myelosuppressive chemotherapy. Consequently, antifungal prophylaxis has been extensively studied for more than 20 years. Nonabsorbable polyenes reduce superficial mycoses but are not effective in preventing or treating invasive fungal infections. Intravenous amphotericin B and the newer azoles were used in numerous clinical trials, but the value of antifungal prophylaxis in defined risk groups with cancer is still open to discussion. Recipients of allogeneic stem cell transplants and patients with a relapsed leukemia are high-risk patient populations. In addition, certain risk factors are well defined, for example, neutropenia more than 10 days, corticosteroid therapy, sustained immunosuppression, and graft-versus-host disease. In contrast to study efforts, evidence-based recommendations on the clinical use of antifungal prophylaxis according to risk groups are rare. The objective of this review of 50 studies accumulating more than 9000 patients is to assess evidence-based criteria with regard to the efficacy of antifungal prophylaxis in neutropenic cancer patients.

Itraconazole prophylaxis for invasive gingival aspergillosis in neutropenic patients with acute leukemia

BACKGROUND

Due to an increasing number of leukemic patients with invasive gingival aspergillosis during neutropenia (neutrophils <500 cells/microl for >10 days), we evaluated the efficacy of oral itraconazole prophylaxis for preventing this invasive infection at our hospital.

METHODS

This was a retrospective, non-randomized study to analyze the onset of identified invasive gingival aspergillosis among 536 patients with acute leukemia at risk due to the presence of neutropenia from 1991 to 1998. Patients received itraconazole capsules 100 mg/day prophylactically between April 1994 and December 1996, and 200 mg/day between January 1997 and December 1998. Itraconazole serum levels at day 10 were measured in some patients.

RESULTS

In the 39 months prior to April 1994 without itraconazole prophylaxis, 15 cases of invasive gingival aspergillosis were detected in 192 high risk patients with 469 episodes of neutropenia (7.8% of the high risk patients). Between April 1994 and December 1996, using itraconazole prophylaxis at 100 mg/day, there was a dramatic decrease in the infections resulting in 3 of 198 high risk patients with 511 episodes of neutropenia (1.5% of the high risk patients). Furthermore, between January 1997 and December 1998, using itraconazole prophylaxis at 200 mg/day, no cases of the infection were observed in the 146 high risk patients with 380 episodes of neutropenia. The incidence of invasive gingival aspergillosis was significantly lower among patients administered itraconazole than among those without itraconazole (100 mg/day; P = 0.006 and 200 mg/day; P = 0.001). The mean itraconazole serum level in 20 patients receiving 100 mg/day was 71.78 ng/mL and in 16 patients receiving 200 mg/day was 202.67 ng/ml.

CONCLUSIONS

These findings suggest that oral itraconazole could be effective for preventing invasive gingival aspergillosis in neutropenic patients with acute leukemia and warrants further randomized investigation.

Activities of an intravenous formulation of itraconazole in experimental disseminated Aspergillus, Candida, and Cryptococcus infections

An intravenous (i.v.) formulation of itraconazole was evaluated in disseminated fungal infection models in guinea pigs. In acute disseminated Candida albicans and Aspergillus fumigatus infections, treatment at 5 mg/kg of body weight twice a day (b.i.d.) significantly prolonged survival. In these models and in animals with chronic disseminated cryptococcosis, itraconazole given i.v. at 2.5 and 5 mg/kg b.i.d. greatly reduced the proportions of organs with culture-detectable fungal burdens. The efficacy of i.v. itraconazole in these animal models justifies its further investigation for the treatment of life-threatening mycoses in humans.

Prevention and prophylaxis of invasive fungal sinusitis in the immunocompromised patient

Fungal infections are a leading cause of morbidity and mortality among immunocompromised patients. Invasive fungal sinusitis is a devastating complication of immunosuppression. Treatment options are limited and often ineffective, making prevention important. Measures to decrease environmental exposure, indications for antifungal prophylaxis, and limitations of current regimens are discussed.

Antifungal prophylaxis in neutropenia

Despite the widespread prophylactic use of antifungal agents in neutropenic patients, invasive fungal infections continue to emerge as major causes of morbidity and mortality. With the exception of fluconazole prophylaxis in allogeneic marrow transplant recipients, no firm conclusions can be drawn due to the lack of reliable, randomized trials. At the present time, it seems that antifungal chemoprophylaxis is more a matter of faith rather than science. Earlier diagnosis based on noninvasive diagnostic techniques and pre-emptive strategies may offer more promise than a liberal prophylactic approach.

Supportive care in hematological malignancies: hematopoietic growth factors, infections, transfusion therapy

This article focuses on a selected number of topics among recent developments in the supportive care of hematological malignancies. The first section focuses on the role of hematopoietic growth factors, such as granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, thrombopoietin, interleukin-11, and keratinocyte growth factor. The following sections discuss the management of fungal and viral infections as well as changes in the current policies of platelet transfusion. The focus of this review is on the clinical utility and economic feasibility of the published findings.