Candidemia and other Candida infections (intra-abdominal abscess and peritonitis)

The recommended dose is a single 200 mg loading dose of ERAXIS on Day 1, followed by a 100 mg once daily maintenance dose thereafter. Duration of treatment should be based on the patient's clinical response. In general, antifungal therapy should continue for at least 14 days after the last positive culture.

Esophageal Candidiasis

The recommended dose is a single 100 mg loading dose of ERAXIS on Day 1, followed by a 50 mg once daily maintenance dose thereafter. Patients should be treated for a minimum of 14 days and for at least 7 days following resolution of symptoms. Duration of treatment should be based on the patient's clinical response. Because of the risk of relapse of esophageal candidiasis in patients with HIV infection, suppressive antifungal therapy may be considered after a course of treatment.

Candidemia and other Candida infections (intra-abdominal abscess and peritonitis)

The recommended dose is a single loading dose of 3 mg/kg (not to exceed 200 mg) of ERAXIS on Day 1, followed by a once daily maintenance dose of 1.5 mg/kg (not to exceed 100 mg) of ERAXIS thereafter. Overall antifungal treatment should continue for at least 14 days after the last positive culture.

Reconstitution of the 50 mg/vial

Aseptically reconstitute each 50 mg vial with 15 mL of sterile Water for Injection to provide a concentration of 3.33 mg/mL.

Reconstitution of the 100 mg/vial

Aseptically reconstitute each 100 mg vial with 30 mL of sterile Water for Injection to provide a concentration of 3.33 mg/mL.

Storage of the Reconstituted Solution

ERAXIS reconstituted solution can be stored at 25°C (77°F) for up to 24 hours prior to dilution into the infusion solution. Chemical and physical in-use stability of the reconstituted solution has been demonstrated for 24 hours at 25°C (77°F). From a microbiological point of view, following good aseptic practices, the reconstituted solution can be utilized for up to 24 hours when stored at 25°C.

Adult Patients

Aseptically transfer the contents of the reconstituted vial(s) into the appropriately sized IV bag (or bottle) containing either 5% Dextrose Injection, USP or 0.9% Sodium Chloride Injection, USP (normal saline). See Table 1 for the dilution to a concentration of 0.77 mg/mL for the final infusion solution and infusion instructions for each dose. The rate of infusion should not exceed 1.1 mg/minute (equivalent to 1.4 mL/minute or 84 mL/hour when reconstituted and diluted per instructions) [see Warnings and Precautions (5.2)].

Pediatric Patients

The volume of infusion solution required to deliver the dose is dependent on the weight of the child. The reconstituted solution must be further diluted to a concentration of 0.77 mg/mL for the final infusion solution. A programmable syringe or infusion pump is recommended. The rate of infusion should not exceed 1.1 mg/minute (equivalent to 1.4 mL/minute or 84 mL/hour when reconstituted and diluted per instructions) [see Warnings and Precautions (5.2)].

Storage of the Infusion Solution

ERAXIS infusion solution can be stored at temperatures up to 25°C (77°F) for up to 48 hours. Do not freeze. Chemical and physical in-use stability of the infusion solution has been demonstrated for 48 hours at 25°C (77°F). From a microbiological point of view, following good aseptic practices, the infusion solution can be utilized for up to 48 hours from preparation when stored at 25°C.

Clinical Trials Experience in Adults

The safety of ERAXIS for Injection was assessed in 929 individuals, including 257 healthy subjects and 672 patients in clinical trials of candidemia, other forms of Candida infections, and esophageal candidiasis. A total of 633 patients received ERAXIS at daily doses of either 50 mg or 100 mg. A total of 481 patients received ERAXIS for ≥14 days.

Clinical Trials Experience in Pediatric Patients with Candidemia/Invasive Candidiasis

The safety of ERAXIS was investigated in 68 pediatric patients from 1 month to less than 18 years of age with candidemia/invasive candidiasis in a prospective, open-label, non-comparative pediatric trial [see Clinical Studies (14.1)]. Overall, the safety profile of ERAXIS in the pediatric patients 1 month and older was similar to that of adults.

Risk Summary

Based on findings from animal studies, ERAXIS can cause fetal harm when administered to a pregnant woman. There are no available human data on the use of ERAXIS in pregnant women to inform a drug-associated risk of adverse developmental outcomes. In animal reproduction studies fetal toxicity was observed in the presence of maternal toxicity when anidulafungin was administered to pregnant rabbits during organogenesis at 4 times the proposed therapeutic maintenance dose of 100 mg/day on the basis of relative body surface area (see Data). Inform pregnant woman of the risk to the fetus.

The estimated background risk of major birth defects and miscarriage for the indicated populations are unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20% respectively.

Data

Risk Summary

There are no data on the presence of anidulafungin in human milk, the effects on the breastfed infant or the effects on milk production. When a drug is present in animal milk, it is likely that the drug will be present in human milk. Anidulafungin was found in the milk of lactating rats (see Data).

The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for ERAXIS and any potential adverse effects on the breastfed child from ERAXIS or from the underlying maternal condition.

Data

General Pharmacokinetic Characteristics

The pharmacokinetics of anidulafungin following intravenous (IV) administration of ERAXIS have been characterized in healthy subjects, special populations and patients. Systemic exposures of anidulafungin are dose-proportional and have low inter-subject variability (coefficient of variation <25%) as shown in Table 5. The steady state was achieved on the first day after a loading dose (twice the daily maintenance dose) and the estimated plasma accumulation factor at steady state is approximately 2.

The clearance of anidulafungin is about 1 L/h and anidulafungin has a terminal elimination half-life of 40–50 hours.

Distribution

The pharmacokinetics of anidulafungin following IV administration are characterized by a short distribution half-life (0.5–1 hour) and a volume of distribution of 30–50 L that is similar to total body fluid volume. Anidulafungin is extensively bound (>99%) to human plasma proteins.

Metabolism

Hepatic metabolism of anidulafungin has not been observed. Anidulafungin is not a clinically relevant substrate, inducer, or inhibitor of cytochrome P450 (CYP450) isoenzymes. It is unlikely that anidulafungin will have clinically relevant effects on the metabolism of drugs metabolized by CYP450 isoenzymes.

Anidulafungin undergoes slow chemical degradation at physiologic temperature and pH to a ring-opened peptide that lacks antifungal activity. The in vitro degradation half-life of anidulafungin under physiologic conditions is about 24 hours. In vivo, the ring-opened product is subsequently converted to peptidic degradants and eliminated.

Excretion

In a single-dose clinical study, radiolabeled (14C) anidulafungin was administered to healthy subjects. Approximately 30% of the administered radioactive dose was eliminated in the feces over 9 days, of which less than 10% was intact drug. Less than 1% of the administered radioactive dose was excreted in the urine. Anidulafungin concentrations fell below the lower limits of quantitation 6 days post-dose. Negligible amounts of drug-derived radioactivity were recovered in blood, urine, and feces 8 weeks post-dose.

Specific Populations

Drug Interactions

In vitro studies showed that anidulafungin is not metabolized by human cytochrome P450 or by isolated human hepatocytes and does not significantly inhibit the activities of human CYP isoforms (1A2, 2B6, 2C8, 2C9, 2C19, 2D6 and 3A) in clinically relevant concentrations. No clinically relevant drug-drug interactions were observed with drugs likely to be co-administered with anidulafungin.

Mechanism of Action

Anidulafungin is a semi-synthetic echinocandin with antifungal activity. Anidulafungin inhibits glucan synthase, an enzyme present in fungal, but not mammalian cells. This results in inhibition of the formation of 1,3-β-D-glucan, an essential component of the fungal cell wall.

Resistance

Echinocandin resistance is due to point mutations within the genes (FKS1 and FKS2) encoding for subunits in the glucan synthase enzyme complex. There have been reports of Candida isolates with reduced susceptibility to anidulafungin, suggesting a potential for development of drug resistance. The clinical significance of this observation is not fully understood.

Antimicrobial Activity

Anidulafungin has been shown to be active against most isolates of the following microorganisms both in vitro and in clinical infections:

Candida albicans
Candida glabrata
Candida parapsilosis
Candida tropicalis

The following in vitro data are available, but their clinical significance is unknown. At least 90 percent of the following fungi exhibit an in vitro minimum inhibitory concentration (MIC) less than or equal to the susceptible breakpoint for anidulafungin against isolates of the following Candida species. However, the effectiveness of anidulafungin in treating clinical infections due to these fungi has not been established in adequate and well-controlled clinical trials:

Candida guilliermondii
Candida krusei

Susceptibility Testing

For specific information regarding susceptibility test interpretive criteria and associated test methods and quality control standards recognized by FDA for this drug, please see: https://www.fda.gov/STIC.

Adults Candidemia and Other Candida Infections (Intra-abdominal Abscess and Peritonitis) Trial

The safety and efficacy of ERAXIS were evaluated in a Phase 3, randomized, double-blind study of patients with candidemia and/or other forms of invasive candidiasis. Patients were randomized to receive once daily IV ERAXIS (200 mg loading dose followed by 100 mg maintenance dose) or IV fluconazole (800 mg loading dose followed by 400 mg maintenance dose). Patients were stratified by APACHE II score (≤20 and >20) and the presence or absence of neutropenia. Patients with Candida endocarditis, osteomyelitis or meningitis, or those with infection due to C. krusei, were excluded from the study. Treatment was administered for at least 14 and not more than 42 days. Patients in both study arms were permitted to switch to oral fluconazole after at least 10 days of intravenous therapy, provided that they were able to tolerate oral medication, were afebrile for at least 24 hours, and the last blood cultures were negative for Candida species.

Patients who received at least one dose of study medication and who had a positive culture for Candida species from a normally sterile site before entry into the study (modified intent-to-treat [MITT] population) were included in the analysis of global response at the end of IV therapy. A successful global response required clinical cure or improvement (significant, but incomplete resolution of signs and symptoms of the Candida infection and no additional antifungal treatment), and documented or presumed microbiological eradication. Patients with an indeterminate outcome were analyzed as failures in this population.

Two hundred and fifty-six patients in the intent-to-treat (ITT) population were randomized and received at least one dose of study medication. In ERAXIS-treated patients, the age range was 16–89 years, the gender distribution was 50% male and 50% female, and the race distribution was 71% White, 20% Black/African American, 7% Hispanic, 2% other races. The median duration of IV therapy was 14 and 11 days in the ERAXIS and fluconazole arms, respectively. For those who received oral fluconazole, the median duration of oral therapy was 7 days for the ERAXIS arm and 5 days for the fluconazole arm.

Patient disposition is presented in Table 9.

Two hundred and forty-five patients (127 ERAXIS, 118 fluconazole) met the criteria for inclusion in the MITT population. Of these, 219 patients (116 ERAXIS, 103 fluconazole) had candidemia only. Risk factors for candidemia among patients in both treatment arms in this study were: presence of a central venous catheter (78%), receipt of broad-spectrum antibiotics (69%), recent surgery (42%), recent hyperalimentation (25%), and underlying malignancy (22%). The most frequent species isolated at baseline was C. albicans (62%), followed by C. glabrata (20%), C. parapsilosis (12%) and C. tropicalis (11%). The majority (97%) of patients were non-neutropenic (ANC >500) and 81% had APACHE II scores less than or equal to 20.

Global success rates in patients with candidemia and other Candida infections are summarized in Table 10.

Table 11 presents global response by patients with candidemia or multiple sites of Candida infection and mortality data for the MITT population.

Pediatric Candidemia/Invasive Candidiasis Trial

A prospective, open-label, non-comparative, multinational trial (National Clinical Trial (NCT) number 00761267) assessed the safety and efficacy of ERAXIS in 68 pediatric patients aged 1 month to <18 years with candidemia/invasive candidiasis. Patients were stratified by age (1 month to <2 years, 2 to <5 years, and 5 to <18 years) and received once daily intravenous ERAXIS (3 mg/kg loading dose on Day 1, and 1.5 mg/kg daily maintenance dose thereafter) followed by an optional switch to oral fluconazole (6–12 mg/kg/day, maximum 800 mg/day) up to Day 49. Patients were followed at 2 and 6 weeks after EOT.

Among 68 ERAXIS-treated patients, 64 had microbiologically confirmed Candida infection and were evaluated for efficacy in the modified intent-to-treat (MITT) population. Overall, 59 patients (92.2%) had Candida isolated from blood only. The most commonly isolated pathogens were Candida albicans (25 [39.1%] patients), followed by Candida parapsilosis (17 [26.6%] patients), and Candida tropicalis (9 [14.1%] patients). A successful global response was defined as having both successful clinical (cure or improvement) and microbiological (eradication or presumed eradication) response. The overall rates of successful global response in the MITT population are presented in Table 12 below.

ERAXIS vials

ERAXIS (unreconstituted) vials should be stored in a refrigerator at 2°C – 8°C (36°F – 46°F). Do not freeze.

Excursions for 96 hours up to 25°C (77°F) are permitted, and the vial can be returned to storage at 2°C – 8°C (36°F – 46°F).

Reconstituted solution

ERAXIS reconstituted solution can be stored at up to 25°C (77°F) for up to 24 hours [see Dosage and Administration (2.3)].

Infusion Solution

ERAXIS infusion solution can be stored at temperatures up to 25°C (77°F) for up to 48 hours. Do not freeze [see Dosage and Administration (2.4)].