A Randomized Controlled Trial of a Novel Formulation of Ketorolac Tromethamine for Continuous Infusion (NTM-001) in Healthy Volunteers

Abstract

Introduction

There is an urgent unmet medical need for a safe, effective, nonopioid analgesic agent for postoperative pain control.

Methods

This first-in-man study was designed to explore a data-informed, model-based candidate dosage regimen and safety of a novel formulation of ketorolac tromethamine (NTM-001) delivered as a 12.5-mg intravenous (IV) bolus followed immediately by 3.5 mg/h continuous infusion over 24 h compared versus IV bolus dosing of 30 mg generic ketorolac every 6 h. The study evaluated pharmacokinetic parameters and safety profiles based on a targeted product profile. A graphical overlay method and model-based comparisons were used to assess the concentration–time curve.

Results

Healthy adults (n = 28, 50% men) received NTM-001 and bolus dosing in an open-label crossover design. Observed plasma concentrations were tightly aligned with predicted values with no outliers. Graphical overlay comparisons showed low between-subject variability and agreed with forecasted concentration–time targets. The pharmacokinetic (PK) base models fit with preliminary PK data from both the NTM-001 and bolus groups with model fit median profiles within 95% prediction limits and no updating of the models. Consistent with serum concentration–time profiles, pain relief scores fell within predicted limits, with initial pain relief scores of NTM-001 slightly above the target profile, likely because the initial serum ketorolac concentrations were somewhat higher than predicted. The 24-h pain relief predicted for NTM-001 based on the area under the median ketorolac pain relief versus time curve was about 6% below that of the pain relief target. Both treatments were well tolerated and no subject withdrew because of adverse events.

Conclusions

The PK parameters for NTM-001 and comparator bolus were similar to the modeling targets with no updating of the base model. There were no outliers and little intersubject variability. NTM-001 delivered as a bolus of 12.5 mg IV followed immediately by continuous infusion of 3.5 mg/h using a standard hospital infusion pump may offer an alternative to opioids for acute postoperative pain control.

Plain Language Summary

Opioids are effective analgesics but the risk for opioid use disorder (OUD) and opioid-associated side effects limit their use even for postoperative pain. Ketorolac is an established nonopioid pain reliever that may be as efficacious as morphine in this setting. This study evaluated a new ketorolac product (NTM-001) compared to generic ketorolac. Both were delivered using a standard hospital intravenous (IV) drug pump. The new ketorolac product was administered first with a loading dose of 12.5 mg followed immediately by a continuous IV infusion of 3.5 mg/h. This was compared to IV generic ketorolac administered as a bolus dose of 30 mg every 6 h. The study enrolled 28 healthy adult volunteers. As a crossover study, subjects underwent both treatments: once with the continuous infusion (NTM-001) and once with the IV injection every 6 h (bolus group) with a “washout” period in between. Blood was collected from the volunteers at several time-determined points during the 48-h study to chart ketorolac concentrations in the blood, which can be correlated to predicted levels of pain control. In this study, blood concentrations of ketorolac were reliably predictable and side effects were generally mild with no unexpected adverse events. The continuous infusion group achieved analgesic benefit at a lower total dose than did the every-6-h group over 24 h.