A Study With Lidocaine 5% Medicated Plaster in Patients Suffering From Postherpetic Neuralgia

Treatment emergent adverse events (TEAEs) were continually monitored through the main period of the study (12 months). Incidences were calculated based on all events reported up to 12 months. No primary endpoint was defined for this study.

Pain relief was assessed starting 1 week (new participants) or 6 weeks after treatment initiation (participants from KF10004/01) until the final visit of the main study period. The average pain relief during the last week before the visit was assessed using a 6-item verbal rating scale (VRS) with categories 1 = worse, 2 = no pain relief, 3 = slight, 4 = moderate, 5 = a lot, and 6 = complete.

The participant's recall of worst, least, and average pain intensity in the last week prior to each visit were assessed using an 11-point Numeric Rating Scale (NRS from 0 = no pain to 10 = pain as bad as you can imagine).

The participant's recall of average pain relief during plaster application in the last week prior to each visit in the extension period was assessed using a 6-item VRS with categories 1 = worse, 2 = no pain relief, 3 = slight, 4 = moderate, 5 = a lot, and 6 = complete.

Treatment emergent adverse events were continually monitored for or asked about at each visit scheduled every 6 months in the extension period. The extension period lasted for up to 4.4 years and included a follow-up visit (1-2 weeks after last regular 6-month visit [or early withdrawal]). Adverse event incidences were calculated based on all events reported in the extension period.

Allodynia severity was rated using the following categorical scale: 0 = no pain or discomfort to touch; 1 = uncomfortable, but tolerable to touch; 2 = painful; 3 = extremely painful, participant cannot stand touching. The test was conducted by means of a brush (type N12). The painful PHN area was stroked with the brush and the intensity of allodynic pain was assessed by the participant.

Investigators were asked to describe their overall impression of the change of the participant's condition/pain by answering the following question: "Compared to the patient's condition at admission to the project, how much has he/she changed?" The categorical scale comprises the categories not assessed = 0, very much improved = 1, much improved = 2, minimally improved = 3, no change = 4, minimally worse = 5, much worse = 6, and very much worse = 7.

The Short Form 36 Quality of Life Index (SF-36 [Trade Mark]) standard version with a 4-week recall period was used as a self-assessment.

Eleven questions were answered on binomial (Yes/No) or on 3-, 5-, or 6-point categorical scales to generate the 8 raw scales (Physical Functioning, Role-Physical, Bodily Pain, General Health, Vitality, Social Functioning, Role-Emotional, Mental Health). Higher values of the raw scales represent a better outcome. The raw scales were converted into a transformed scale (transformed scale = [(actual raw score - lowest possible raw score) / possible raw score range] x 100).

The SF-MPQ includes 15 words (11 sensory, 4 affective). Each word or phrase is rated on a 4-point intensity scale (0 = none, 1 = mild, 2 = moderate, and 3 = severe). In addition, the 6-point Present Pain Intensity (PPI) rating (no pain, mild, discomforting, distressing, horrible, excruciating) is included as is a visual analogue scale for rating pain intensity. Total score as well as sensory and affective sub-scores were calculated.

Investigators were asked to describe their overall impression of the change of the participant's condition/pain by answering the following question: "Compared to the patient's condition at admission to the project, how much has he/she changed?" (categories: not assessed = 0, very much improved = 1, much improved = 2, minimally improved = 3, no change = 4, minimally worse = 5, much worse = 6, very much worse = 7).

Participants were asked to describe their overall impression of change of their condition/pain by answering the following question: "Compared to your pain at admission to the project, how much has it changed?" (categories: not assessed = 0, very much improved = 1, much improved = 2, minimally improved = 3, no change = 4, minimally worse = 5, much worse = 6, very much worse = 7).

The assessment of the investigational medicinal product (IMP) was made on a 5-point categorical scale (poor, fair, good, very good, excellent). Investigators responded to the following question: "How would you rate the study medication the patient received for pain?"

The assessment of the IMP was made on a 5-point categorical scale (poor, fair, good, very good, excellent). Participants responded to the following question: "How would you rate the study medication you received for pain?"

For each participant, the number of different medications taken for PHN symptoms was determined at enrollment into the and at the last assessment in the study. Participants were classified into 5 groups: 0, 1, 2, 3, and more than 3 different substances taken. Shifts were determined for enrollment to last assessment in the study.