5% lidocaine medicated plaster versus pregabalin in post-herpetic neuralgia and diabetic polyneuropathy: an open-label, non-inferiority two-stage RCT study.
OBJECTIVE
To compare efficacy and safety of 5% lidocaine medicated plaster with pregabalin in patients with post-herpetic neuralgia (PHN) or painful diabetic polyneuropathy (DPN).


METHODS
This was a two-stage adaptive, randomized, open-label, multicentre, non-inferiority study. Data are reported from the initial 4-week comparative phase, in which adults with PHN or painful DPN received either topical 5% lidocaine medicated plaster applied to the most painful skin area or twice-daily pregabalin capsules titrated to effect according to the Summary of Product Characteristics. The primary endpoint was response rate at 4 weeks, defined as reduction averaged over the last three days from baseline of > or = 2 points or an absolute value of < or = 4 points on the 11-point Numerical Rating Scale (NRS-3). Secondary endpoints included 30% and 50% reductions in NRS-3 scores; change in allodynia severity rating; quality of life (QoL) parameters EQ-5D, CGIC, and PGIC; patient satisfaction with treatment; and evaluation of safety (laboratory parameters, vital signs, physical examinations, adverse events [AEs], drug-related AEs [DRAEs], and withdrawal due to AEs).


RESULTS
Ninety-six patients with PHN and 204 with painful DPN were analysed (full analysis set, FAS). Overall, 66.4% of patients treated with the 5% lidocaine medicated plaster and 61.5% receiving pregabalin were considered responders (corresponding numbers for the per protocol set, PPS: 65.3% vs. 62.0%). In PHN more patients responded to 5% lidocaine medicated plaster treatment than to pregabalin (PPS: 62.2% vs. 46.5%), while response was comparable for patients with painful DPN (PPS: 66.7% vs 69.1%). 30% and 50% reductions in NRS-3 scores were greater with 5% lidocaine medicated plaster than with pregabalin. Both treatments reduced allodynia severity. 5% lidocaine medicated plaster showed greater improvements in QoL based on EQ-5D in both PHN and DPN. PGIC and CGIC scores indicated greater improvement for 5% lidocaine medicated plaster treated patients with PHN. Improvements were comparable between treatments in painful DPN. Fewer patients administering 5% lidocaine medicated plaster experienced AEs (safety set, SAF: 18.7% vs. 46.4%), DRAEs (5.8% vs. 41.2%) and related discontinuations compared to patients taking pregabalin.


CONCLUSIONS
5% lidocaine medicated plaster showed better efficacy compared with pregabalin in patients with PHN. Within DPN, efficacy was comparable for both treatments. 5% lidocaine medicated plaster showed a favourable efficacy/safety profile with greater improvements in patient satisfaction and QoL compared with pregabalin for both indications, supporting its first line position in the treatment of localized neuropathic pain.
Baron
Ralf
R
Division of Neurological Pain Research and Therapy, Department of Neurology, Universitätsklinikum Schleswig-Holstein, Campus Kiel, Kiel, Germany. r.baron@neurologie.uni-kiel.de
Mayoral
Victor
V
Leijon
Göran
G
Binder
Andreas
A
Steigerwald
Ilona
I
Serpell
Michael
M
D000368:Aged; D000465:Algorithms; D000700:Analgesics / Q000008:administration & dosage / Q000009:adverse effects; D002370:Casts, Surgical / Q000009:adverse effects; D003929:Diabetic Neuropathies / Q000150:complications / Q000188:drug therapy*; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D051474:Neuralgia, Postherpetic / Q000150:complications / Q000188:drug therapy*; D009994:Osmolar Concentration; D010146:Pain / Q000188:drug therapy / Q000209:etiology; D000069583:Pregabalin; D016896:Treatment Outcome; D005680:gamma-Aminobutyric Acid / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*
D000700:Analgesics; D000069583:Pregabalin; D005680:gamma-Aminobutyric Acid; D008012:Lidocaine