Pharmacokinetics and Safety of Cefazolin 3gm DUPLEX in Adults

This is a Phase 1, open-label, single-dose, multiple-center, study to determine the pharmacokinetics of a single 3 g dose of cefazolin administered as a 30 minute IV infusion prior to surgery in adult subjects weighing \>/= 120 kg. Adult subjects will be enrolled in order to ensure at least 12 subjects complete the study. Enrollment will be competitive across the study sites. All subjects will have Screening and baseline evaluations performed to ensure their eligibility for the study The Screening Period is up to 30 days before administration of study drug on Day 1.

Study drug will be administrated as an infusion over 30 minutes starting approximately 0.5 hours before surgery begins and following institutional guidelines on Day 1 (day of surgery). Planned surgical procedures may be performed outpatient or inpatient and are expected to last no longer than 3 hours.

If the surgery is extended unexpectedly beyond the 3-hour limit, additional doses of study drug are permitted according to institutional guidelines. PK blood sample collection will continue after the administration of an additional dose of cefazolin. Safety in this population will also be assessed.

All subjects will have five (5) individual whole blood samples (4 mL each) collected for the estimation of cefazolin concentration in plasma at the following times after the start of the infusion: 0.5 (+/-10 min) end of infusion, 1 h (+/-15 min), 2 h (+/-15 min), 4 h (+/-15 min) and 8 h (+/-15 min).

Safety will be assessed by monitoring adverse events (AEs), physical examination, vital signs, and clinical laboratory tests. A follow-up visit will be performed on Day 8 (+/-1 day) for safety assessments.

A subject is considered a study completer if he/she has completed all study related procedures through the end of surgery and the required PK sample collections. It is highly preferred that the subjects also participate in the Day 8 (+/-1 day) Safety Follow-up. For subjects who withdraw or are withdrawn before study completion of the study, every effort will be made to perform all Safety Follow up procedures.

Any subject who withdraws or is withdrawn before collection of at least 4 of the 5 PK samples will not be consider as a PK completer. If necessary, additional subjects must be enrolled to ensure that there are at least 12 PK completers.

On Day 8 (+/-1 day), a Safety follow-up will be conducted. If this is an in-person visit, the following will be performed: vital signs, clinical laboratory tests, examination of the infusion site, review of AEs and concomitant medication. If an in-person visit is not possible, every effort will be made to contact the subject by phone and the subjects will be asked about any AEs and concomitant medication they may have taken.