No Clear Exposure-Response Relationship Found for Micafungin in Neonatal Candidiasis
No clear relationship was found between the average daily area under concentration-time curve and mycologic response for micafungin in neonates.
In infants with candidiasis, there is no significant relationship between exposure to micafungin and mycologic response, according to results published in The Pediatric Infectious Disease Journal.
Despite these results, pharmacokinetic (PK)-pharmacodynamic (PD) experiments support higher exposures of micafungin in infants with invasive candidiasis.
The study included infants 3 to 119 days old (n=64). The researchers used micafungin plasma concentrations from the participants to construct a population PK model using Pmetrics™ software. They used Bayesian posterior estimates for participants with invasive candidiasis to evaluate the relationship between drug exposure and mycologic response using logistic regression. Of the 64 infants, 45% (n=29) had invasive candidiasis.
The mean (standard deviation) estimates for clearance and volume in the central compartment were 0.07 (0.05) L/h/1.8 kg and 0.61 (0.53) L/1.8 kg, respectively.
The results indicated that there was no relationship between average daily area under concentration-time curve or average daily area under concentration-time curve and minimum inhibitory concentration ratio and mycologic response (P >.05).
Although not statistically significant, the researchers found that mycologic response was numerically higher when area under concentration-time curves were at or above the PD target.
“While a significant exposure-response relationship was not found, PK-PD experiments support higher exposures of micafungin in infants with invasive candidiasis,” the researchers wrote.
Kovanda LL, Walsh TJ, Benjamin DK Jr, et al. Exposure-response analysis of micafungin in neonatal candidiasis. Pediatr Infect Dis J. 2018;37:580-585.