Post-herpetic neuralgia: 5% lidocaine medicated plaster, pregabalin, or a combination of both? A randomized, open, clinical effectiveness study

Abstract

Objective:

To compare efficacy and safety of 5% lidocaine medicated plaster with pregabalin in patients with post-herpetic neuralgia (PHN), and to assess the benefits of combining both drugs in patients not responding to either single agent.

Study design and methods:

This was a two-stage adaptive, randomised, open-label, multicentre, non-inferiority study (NCT 00414349). The subset of patients with PHN is reported here. Patients with an absolute value of >4 on the NRS-3 were randomly assigned to 4-week treatment with 5% lidocaine medicated plaster or twice-daily pregabalin capsules titrated to effect. Subsequently, patients sufficiently treated with monotherapy (patients with NRS-3 ≤4 at 4 weeks or a reduction on the NRS-3 from baseline of ≥2 points) continued with monotherapy; patients insufficiently treated with monotherapy received both drugs in combination for 8 weeks.

Outcome measures:

Pain according to SF-MPQ and NPSI, onset of effect, reduction in worst pain on the NRS; allodynia severity; quality of life (QoL) based on EQ-5D, SF-36; PGIC; rescue medication intake; adverse events (AEs) monitoring.

Results:

At 4 weeks, SF-MPQ total scores improved by −7.6 ± 6.66 (mean ± SD) under 5% lidocaine medicated plaster and by −5.3 ± 7.93 under pregabalin. NPSI total scores declined by −1.6 ± 1.73 under 5% lidocaine medicated plaster and −1.4 ± 1.87 under pregabalin. Lidocaine plaster was also effective in reducing worst pain and showed a fast onset of effect. During combination treatment, SF-MPQ and NPSI scores, allodynia, EQ-5D and PGIC improved. Incidences of AEs were in line with previous reports for the two treatments and combination therapy was generally well-tolerated.

Conclusions:

Although this open-label study is lacking a placebo control group, the results suggest that 5% lidocaine medicated plaster is at least as effective as pregabalin for pain relief in PHN, with a favourable safety profile and a resulting positive benefit-risk ratio. In patients unresponsive to either monotherapy, combination therapy provides additional efficacy and is well-tolerated.

Key words::

• Lidocaine plaster
• Neuropathic pain
• Post-herpetic neuralgia
• Pregabalin

Transparency

Declaration of funding

Grünenthal GmbH, Aachen, Germany sponsored this study and provided funding for editorial assistance in the preparation of this manuscript.

Declaration of financial/other relationships

No honoraria were paid to the authors for the preparation of this article. S.R. has disclosed that she has received speaking fees from Pfizer and Grünenthal. A.B. has disclosed that he has received honoraria from Pfizer, Allergan and Grünenthal. R.B. has disclosed that he is an advisor to Allergan, Pfizer and Grünenthal, Medtronic, Mundipharma, Eisai, Sanofi-Pasteur, UCB, Lilly, Astellas and Genzyme; and has received research funding from Pfizer, Grünenthal and Genzyme.

Some peer reviewers receive honoraria from CMRO for their review work. The peer reviewers of this paper have disclosed that they have no relevant financial relationships.

Acknowledgement

The authors thank Dr. K. Ostermann and Dr. B. Brett for editorial assistance and publication coordination. All costs associated with the development and the publishing of the present manuscript were met by the sponsor of the study.

The authors retain sole responsibility for the views expressed in this article, which may or may not be shared by the sponsors.

Notes

*Versatis is a registered trade name of Grünenthal GmbH, Aachen, Germany.

†Lyrica is a registered trade name of Pfizer Ltd, Kent, UK.