Clinical Therapeutics/Volume 29, Theme Issue, 2007
Duloxetine for the Management of Diabetic Peripheral
Neuropathic Pain: Evidence-Based Findings from Post Hoc
Analysis of Three Multicenter, Randomized, Double-Blind,
Placebo-Controlled, Parallel-Group Studies
Daniel K. Kajdasz, PhD1; Smriti lyengar, PhD1; Durisala Desaiah, PhD1;
Misha-Miroslav Backonja, MD2;John T. Farrar, MD, MSCE, PhD3; David A. Fishbain, MD4;
Troels S.Jensen, MDS; Michael C. Rowbotham, MD6; Christine N. Sang, MD, MPh7;
Dan Ziegler, MD, MRCP, PhD, FRCPES; and HenryJ. McQuay, MD, FRCA, FRCP 9
1Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana; 2University of Wisconsin,
Madison, Wisconsin; 3Universityof Pennsylvania School of Medicine, Philadelphia, Pennsylvania; 4Miller
School of Medicine, Universityof Miami, Miami, Florida; SArhus University, Danish Pain Research Center,
Arkus, Denmark; 6Universityof California at San Francisco, San Francisco, California; 7Brigham and
Women's Hospital, Harvard Medical School, Boston, Massachusetts; 8German Diabetes Center, Leibniz
Institute at the Heinrich Heine University, DOsseldorf Germany; and 9Churchill Hospital, Pain Relief Unit,
Oxford, United Kingdom
ABSTRACT
Objective: This post hoc analysis was aimed to sum-
marize the efficacy and tolerability of duloxetine as
represented by number needed to treat (NNT) and
number needed to harm (NNH) to provide a clinically
useful assessment of the position of duloxetine among
current agents used to treat diabetic peripheral neuro-
pathic pain (DPNP).
Methods: Data were pooled from three 12-week,
multicenter, randomized, double-blind, placebo-
controlled, parallel-group studies in which patients
received 60 mg duloxetine either QD or BID or place-
bo. NNT was calculated based on rates of response
(defined as _>30% and _>50% reductions from baseline
in the weekly mean of the 24-hour average pain severi-
ty scores); NNH was calculated based on rates of dis-
continuation due to adverse events (AEs).
Results: Patients receiving duloxetine 60 mg QD
and 60 mg BID had NNTs (95% CI) of 5.2 (3.8-8.3)
and 4.9 (3.6-7.6), respectively, based on last observa-
tion carried forward; NNTs of 5.3 (3.8-8.3) for
60 mg QD and 5.7 (4.1-9.7) for 60 mg BID were ob-
tained based on baseline observations carried for-
ward. The NNHs (95% CI) based on discontinuation
due to AEs were 17.5 (10.2-58.8) in the duloxetine
60-mg QD group and 8.8 (6.3-14.7) in the 60-mg
BID group.
Conclusion: These post hoc results suggest that
duloxetine was effective and well tolerated for the man-
agement of DPNP and further support the importance
of duloxetine as a treatment option for clinicians and
patients to assist with the management of DPNP. (Clin
Ther. 2007;29[Theme Issue]:2536-2546) Copyright ©
2007 Excerpta Medica, Inc.
Key words: duloxetine, NNT, NNH, neuropathy,
diabetic peripheral neuropathic pain.
INTRODUCTION
The neurotransmitters serotonin (5-HT) and norepi-
nephrine (NE) regulate pain signals in the central
nervous system, including the spinal cord. 1 As the
roles of 5-HT and NE in the modulation of pain per-
ception have become better understood, dual 5-HT
and serotonin NE reuptake inhibitors (SNRIs)--
including venlafaxine, milnacipran, and duloxetine--
have been assessed in terms of their therapeutic value
as analgesics with more favorable tolerability pro-
Acceptedfor publication September 19, 200 Z
doi:l 0.1016/j.clinthera.2007.12.002
0149-2918/$32.00
Printed in the USA. Reproduction in whole or part is not permitted.
Copyright © 2007 Excerpta Medica, Inc.
2536 Volume 29 Theme Issue