What is the indication for Micafungin (micafungin)?

Indications for Micafungin

Micafungin is FDA-approved for three primary indications in adults and pediatric patients ≥4 months of age: treatment of candidemia and invasive candidiasis (including Candida peritonitis and abscesses), treatment of esophageal candidiasis, and prophylaxis of Candida infections in hematopoietic stem cell transplant recipients. 1

FDA-Approved Treatment Indications

Invasive Candida Infections

• Candidemia, acute disseminated candidiasis, Candida peritonitis, and abscesses are approved treatment targets for micafungin in patients ≥4 months of age 1
• The standard adult dose is 100 mg IV once daily, with mean treatment duration of 15 days (range 10-47 days) in successful cases 1
• For pediatric patients ≤30 kg, the dose is 2 mg/kg once daily (maximum 100 mg) 1
• Micafungin demonstrated non-inferiority to caspofungin and liposomal amphotericin B in large multinational trials for invasive candidiasis 2, 3, 4

Esophageal Candidiasis

• Treatment of esophageal candidiasis is approved in adults and pediatric patients ≥4 months of age 1
• The adult dose is 150 mg IV once daily, with mean treatment duration of 15 days (range 10-30 days) 1
• Pediatric dosing is 3 mg/kg once daily for patients ≤30 kg or 2.5 mg/kg once daily for patients >30 kg (maximum 150 mg) 1
• Micafungin showed non-inferiority to fluconazole and caspofungin in clinical trials 2, 4

FDA-Approved Prophylaxis Indication

Hematopoietic Stem Cell Transplantation

• Prophylaxis of Candida infections in HSCT recipients is approved for patients ≥4 months of age undergoing transplantation 1
• The standard dose is 50 mg IV once daily for adults and 1 mg/kg once daily (maximum 50 mg) for pediatric patients 1
• Mean duration of prophylaxis in successful cases was 19 days (range 6-51 days) 1
• Micafungin was superior to fluconazole (80.0% vs 73.5% treatment success) in a large multinational trial of HSCT recipients 5, 3

Guideline-Supported Extended Uses

Neutropenic Patients with Hematologic Malignancies

• The IDSA recommends micafungin as prophylaxis in stem cell transplant recipients during neutropenia (Category A-I evidence) 2
• The NCCN endorses echinocandins including micafungin as Category 2B options for prophylaxis in neutropenic AML/MDS patients receiving induction or reinduction chemotherapy 2, 5
• Prophylaxis is recommended when anticipated neutropenia duration is ≥7 days and institutional invasive fungal infection rates are 6-10% or higher 5
• The ESCMID guideline supports micafungin for empirical treatment in neutropenic patients with persistent fever (Grade B, Level II evidence) 2

Critical Advantage Over Azoles

• Micafungin has minimal drug-drug interactions, making it particularly valuable when concurrent chemotherapy is planned 5
• This contrasts with azoles (voriconazole, posaconazole), which are CYP3A4 inhibitors that can cause toxicity with proteasome inhibitors, tyrosine kinase inhibitors, and vinca alkaloids 2
• Azoles should be stopped several days before potentially interacting chemotherapy drugs, whereas micafungin can be continued 2

Spectrum of Activity

Candida Species Coverage

• Micafungin provides excellent coverage against all clinically relevant Candida species including C. albicans, C. glabrata, C. tropicalis, C. parapsilosis, and C. krusei 5, 3, 6
• It demonstrates fungicidal activity against Candida species, including azole-resistant isolates 5, 6, 7
• The drug shows fungistatic activity against Aspergillus species, with some clinical efficacy in refractory aspergillosis 2, 6, 7

Activity Against Resistant Organisms

• Micafungin maintains activity against fluconazole-resistant C. glabrata isolates 8
• It has a low propensity for emergence of resistant isolates during therapy 3, 8

Important Limitations and Contraindications

Inadequately Studied Conditions

• Micafungin has not been adequately studied in patients with Candida endocarditis, osteomyelitis, or meningoencephalitis 1
• The efficacy against non-Candida fungi has not been established, though some activity against Aspergillus exists 1

Clinical Considerations

• Intravascular catheter removal is strongly recommended in candidemia cases (Category A-II evidence) 2
• Dilated ophthalmological examination should be performed in all candidemia patients to exclude Candida endophthalmitis, ideally after candidemia is controlled 2
• In neutropenic patients, ophthalmological examination should be delayed until neutrophil count recovery 2

Dosing Advantages

Practical Benefits

• Once-daily IV administration with no dose adjustments needed for renal dysfunction or moderate hepatic impairment 6, 4
• Relatively few drug-drug interactions compared to azoles 5, 3, 4
• Excellent tolerability with low rates of drug-related adverse events (8-14.4% in clinical trials) 5
• Minimal nephrotoxicity and hepatotoxicity compared to amphotericin B formulations 5, 4