A randomized, double-blind, placebo-controlled, multicenter clinical trial evaluated the sedative properties of PRECEDEX in adult patients having a variety of elective surgeries/procedures performed under monitored anesthesia care. The sedative properties of PRECEDEX were evaluated by comparing the percent of adult patients not requiring rescue midazolam to achieve a specified level of sedation using the standardized Observer’s Assessment of Alertness/Sedation Scale. Adult patients were randomized to receive a loading infusion of either PRECEDEX 1 mcg/kg, PRECEDEX 0.5 mcg/kg, or placebo (normal saline) given over 10 minutes and followed by a maintenance infusion started at 0.6 mcg/kg/hr. The maintenance infusion of study drug could be titrated from 0.2 mcg/kg/hr to 1 mcg/kg/hr to achieve the targeted sedation score (Observer’s Assessment of Alertness/Sedation Scale ≤4). Adult patients were allowed to receive rescue midazolam as needed to achieve and/or maintain an Observer’s Assessment of Alertness/Sedation Scale ≤4. After achieving the desired level of sedation, a local or regional anesthetic block was performed.

A randomized, double-blind, placebo-controlled, multicenter clinical trial evaluated PRECEDEX in adult patients undergoing awake fiberoptic intubation prior to a surgical or diagnostic procedure. The sedative properties of PRECEDEX were evaluated by comparing the percent of adult patients requiring rescue midazolam to achieve or maintain a specified level of sedation using the Ramsay Sedation Scale score of ≥2. Adult patients were randomized to receive a loading infusion of PRECEDEX 1 mcg/kg or placebo (normal saline) given over 10 minutes and followed by a fixed maintenance infusion of 0.7 mcg/kg/hr. After achieving the desired level of sedation, topicalization of the airway occurred. Adult patients were allowed to receive rescue midazolam as needed to achieve and/or maintain a Ramsay Sedation Scale score of ≥2.

The safety and efficacy of PRECEDEX for sedation of non-intubated pediatric patients aged 1 month to less than 17 years undergoing MRI scans was evaluated in one randomized, double-blind, dose-ranging, dose‑controlled multicenter clinical trial utilizing 3 different PRECEDEX dosages. The sedative properties of PRECEDEX were evaluated by age group and by the percent of pediatric patients at the high dose level versus the low dose level who did not require concomitant propofol to complete the MRI scan.

A total of 122 pediatric patients were randomized to the PRECEDEX low dose group (42 of 122), the middle dose group (42 of 122) or the high dose treatment group (38 of 122). All patients received a PRECEDEX loading dose infusion over 10 minutes followed by a maintenance infusion for the duration of the MRI scan. If an adequate level of sedation was not achieved within 5 minutes after the start of the PRECEDEX maintenance infusion, patients could receive concomitant propofol as needed based on clinical judgment to achieve and/or maintain adequate sedation.

The primary efficacy results from this pediatric procedural sedation study are summarized in the table below. In the combined age group, the percent of pediatric patients not requiring concomitant propofol was 14.3% (6/42) in the low dose group and 63.2% (24/38) in the high dose group. The percentage of patients at the PRECEDEX high dose who completed the MRI without concomitant propofol was statistically greater than the percentage in the PRECEDEX low dose group (p<0.001). 

Secondarily, the sedative properties were also evaluated by examining the percent of time at a target sedation score using the Pediatric Sedation State Scale (PSSS). The PSSS is a validated 6-point scale specifically designed for evaluating pediatric patients undergoing sedation for diagnostic and therapeutic procedures. The PSSS measures the effectiveness and quality of procedural sedation in children. The target sedation level was indicated by a PSSS score of 2 (i.e., patient is quiet [asleep or awake], not moving during procedure, has no frown [or brow furrow] indicating pain or anxiety and no verbalization of any complaint).

In the PRECEDEX high dose group, pediatric patients in both the combined and individual age group were at the target sedation rating scale score (PSSS of 2) for a mean >87% of the time during the PRECEDEX maintenance infusion. In both the combined and individual age group, an increase in the percentage of time at the target sedation rating scale score (PSSS of 2) was observed with increasing PRECEDEX dosage.