Diclofenac potassium liquid-filled soft gelatin capsules for the treatment of postbunionectomy pain

Abstract

Objective:

Diclofenac potassium liquid-filled soft gelatin capsule (DPSGC) is a rapidly absorbed formulation of diclofenac approved for the treatment of mild to moderate acute pain in adults (≥18 years of age). The objective of this study was to investigate the efficacy and safety of DPSGC 25 mg in a multicenter, randomized, double-blind, placebo-controlled study in patients experiencing pain following first metatarsal bunionectomy.

Research design and methods:

Patients experiencing a requisite level of pain (≥4 based on an 11-point numeric pain rating scale [NPRS]; 0 = no pain, 10 = worst pain possible) on the day following surgery were randomized to receive DPSGC 25 mg or placebo. Patients received a second dose (remedication) on request or at 8 hours postdose followed by additional doses every 6 hours through the end of postsurgery Day 4. Rescue medication (hydrocodone/acetaminophen) was available as needed after the second dose.

Clinical trial registration:

NCT00375934.

Main outcome measure:

The primary efficacy endpoint was the average NPRS score over the 48 hour inpatient multiple-dose period.

Results:

DPSGC provided a significant improvement in mean 48 hour NPRS scores over placebo (3.29 vs 5.74, respectively; p < 0.0001), as well as for summed pain intensity difference (203.1 vs 86.6; p < 0.0001). Patients treated with DPSGC experienced a faster onset of meaningful pain relief compared with placebo (p = 0.0034). Rescue medication use on Day 1 and Day 2 was reduced in the DPSGC group compared with placebo (53.5% vs 92.1% on Day 1; 30.3% vs 67.3% on Day 2; p < 0.0001). DPSGC was well tolerated and no patients treated with DPSGC reported serious adverse events. As with any study, there are potential limitations including study design and patient population.

Conclusion:

These results indicate that DPSGC reduced pain in patients who underwent bunionectomy and this novel formulation of diclofenac potassium may be a practical option for treating mild to moderate acute pain.

Key words:

• Bunionectomy
• Diclofenac potassium
• Dispersion technology
• Pain relief

Transparency

Declaration of funding

This study was funded by Xanodyne Pharmaceuticals, Inc., Newport, KY, USA. Xanodyne also provided funding for editorial support in the development of this article.

Declaration of financial/other relationships

S.E.D. has disclosed that he is an employee of Premier Research Group, Ltd, whose clinical research centers were involved with conducting the studies contributing to this manuscript. D.R.B. has disclosed that he has stock ownership in MacuClear, Inc., and acts or has acted as a consultant for Theraquest Biosciences, Inc. F.C., M.E.M., and M.H.G. have no conflicts of interest to report. S.E.B. has disclosed that he is a full-time employee of Xanodyne Pharmaceuticals.

Acknowledgment

The authors thank Xanodyne for its support of this manuscript. They also thank Lamara D. Shrode, PhD, CMPP, of the JB Ashtin Group, Inc. who, on the behalf of Xanodyne, assisted in the development of a first draft based on an author-approved outline and assisted in implementing author revisions.

Notes

*Zipsor is a registered trade name of Xanodyne Pharmaceuticals, Inc., Newport, KY, USA.

†ProSorb is a registered trade name of Xanodyne Pharmaceuticals, Inc., licensed from AAIPharma, Inc., Wilmington, NC, USA.