Minocycline Pharmacokinetics (ACUMIN)

This is a Phase IV, multi-center open-label pharmacokinetic trial studying the pharmacokinetics and pharmacodynamics of a single dose of Minocin IV. Up to 67 subjects will be enrolled to obtain 50 evaluable, ICU patients who are already receiving antimicrobial therapy for a known or suspected Gram-negative infection. The entire study duration will be approximately 16 months and each subject participation duration will be approximately 2 days. The study will be conducted at approximately 13 clinical sites. Each subject will receive a single 200 mg dose of Minocin IV infused over approximately 60 minutes. Each subject will have 7 PK samples collected (1 pre-dose, 6 post-dose) at designated time points over a \~48 hour period following the start of the Minocin IV infusion. The primary objectives are: 1) To characterize minocycline PK at the population level in critically-ill adults, with illness known or suspected to be caused by infection with Gram-negative bacteria and 2) To assess patient-level and clinical covariates associated with minocycline pharmacokinetic properties in critically-ill adults, with illness known or suspected to be caused by infection with Gram-negative bacteria.