Micafungin
| Evidence Level: L3 | Predicted Indications: 1 |
Table of Contents
Micafungin: From Systemic Candida Infections to Urinary Tract Infection
One-Sentence Summary
Micafungin is an echinocandin antifungal marketed in the US as an injectable, used mainly against Candida infections. The original indication is not in the Evidence Pack and comes from general pharmacology knowledge. The TxGNN model predicts it may be effective for urinary tract infection (Candida UTI / candiduria). Support is currently 0 registered clinical trials and 13 publications, all non-randomized (PK study, retrospective cohorts, case series and case reports).
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not stated in the Evidence Pack (US label text is empty). General knowledge: invasive Candida infections |
| Predicted New Indication | Urinary tract infection |
| TxGNN Prediction Score | 99.03% |
| Evidence Level | L3 |
| US Market Status | ✓ Marketed |
| Number of NDAs | 20 (includes ANDA generics) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Micafungin is an echinocandin that inhibits 1,3-beta-D-glucan synthase and disrupts the fungal cell wall. It is active against Candida species, including azole-resistant C. glabrata and C. krusei, and some C. auris isolates. The Evidence Pack does not include mechanism-of-action data, so this description comes from general pharmacology.
Candida is the relevant pathogen in fungal UTI and candiduria, so the link between the original and new indication is plausible. The main obstacle is pharmacokinetic: echinocandins have traditionally been considered poor options for urinary infections because little active drug is excreted in urine.
Some clinical reports argue against that view. A pharmacokinetic study (PMID 27424599) reports urinary micafungin levels sufficient to treat Candida UTI. Retrospective series and case reports describe eradication of candiduria, including in azole-resistant cases. The high TxGNN score is therefore biologically plausible, but it rests on non-randomized evidence.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
Study types are as classified in the Evidence Pack. Abstracts were truncated, so some outcomes are not visible.
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 27424599 | 2016 | PK study | Int J Antimicrob Agents | Six UTI cases treated successfully with micafungin, four with fluconazole-resistant Candida. Authors conclude urinary micafungin levels are sufficient for Candida UTI. |
| 27587066 | 2016 | Retrospective cohort | Int Urol Nephrol | Examined candiduria elimination rates in micafungin-treated hospitalized patients. Result figures are not visible in the truncated abstract. |
| 35146837 | 2022 | Retrospective pediatric cohort | Pediatr Int | Reported outcomes of critically ill children given micafungin for hospital-acquired Candida UTI, including success rates by species. Result figures are not visible. |
| 26937340 | 2016 | Case series | Med Mycol Case Rep | Five patients received at least 6 days of parenteral micafungin. All had resolution of baseline candiduria within 30 days of treatment completion. |
| 31111613 | 2019 | Case report | Transpl Infect Dis | Chronic symptomatic C. krusei UTI in a liver and kidney transplant recipient, treated with increased-dose micafungin. The title reports successful eradication. |
| 38827222 | 2024 | Case report | Front Pediatr | C. glabrata urinary infection in a premature neonate treated with micafungin. |
| 40765059 | 2025 | Case report (from title) | J Pharm Health Care Sci | C. glabrata pyelonephritis and bacteremia in a patient on an SGLT2 inhibitor, successfully treated with micafungin. |
| 38681664 | 2024 | Case report | Med Mycol Case Rep | Renal fungus ball from C. glabrata (micafungin-susceptible) resolved with antifungal therapy, endoscopic extraction and stenting. Micafungin’s specific role cannot be isolated. |
| 29109159 | 2018 | Retrospective cohort (indirect) | Antimicrob Agents Chemother | Asymptomatic candiduria is often overtreated with antifungals against guideline advice. This is a caution on appropriate use, not efficacy evidence. |
| 24182454 | 2014 | Surveillance study (indirect) | Int J Antimicrob Agents | 1,218 US Candida bloodstream infection episodes with antifungal susceptibility data, including micafungin. It concerns bloodstream, not urinary, infection. |
US Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| NDA021506 | Mycamine (Astellas Pharma US) | Injection, powder, lyophilized, for solution | Not provided in the data |
| NDA216142 | Micafungin in Sodium Chloride (Baxter Healthcare) | Injection | Not provided in the data |
| ANDA213363 | Micafungin (Sagent Pharmaceuticals) | Injection, powder, lyophilized, for solution | Not provided in the data |
| ANDA207344 | Micafungin (Fresenius Kabi USA) | Injection, powder, lyophilized, for solution | Not provided in the data |
| ANDA215381 | Micafungin (Meitheal Pharmaceuticals) | Injection, powder, lyophilized, for solution | Not provided in the data |
All listed products are injectables. The Evidence Pack shows 20 authorizations in total, and these are the first five.
Safety Considerations
Please refer to the package insert for safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: The biological rationale is plausible, and PK data plus case-level reports suggest micafungin can clear Candida from the urinary tract. However, there are no registered trials, no randomized data, and no comparison against standard therapy such as fluconazole or amphotericin B. The evidence is L3, and the pipeline flags it as a research question. Package-insert safety data are also missing, so safety screening cannot start.
To proceed, the following is needed:
- FDA package insert warnings and contraindications (blocking gap for safety screening)
- Confirmed original indication text and mechanism-of-action data from DrugBank
- Full-text review of the retrospective cohorts (PMIDs 27587066, 35146837) to extract eradication rates and urinary concentrations
- A prospective study or comparative trial in symptomatic Candida UTI, focused on azole-resistant species
- Guidance on patient selection, because asymptomatic candiduria generally should not be treated with antifungals (PMID 29109159)
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.