Microsoft word - oxy3204 synopsis

1. SYNOPSIS
Name of Company:
Name of Finished Product:
Name of Active Ingredient:
Title of the Study: A double-blind, randomised, parallel group study to compare the efficacy, safety, and
tolerability of OxyContin taken in combination with gabapentin, versus placebo with gabapentin, for the
treatment of moderate to severe neuropathic pain in patients with diabetes mellitus.
Investigator(s)/Centre(s): This was a multicentre study across 70 sites. The Principal Investigator was Dr
Magdi Hanna, King’s College Hospital, London.
Publication (Reference): None
Study Dates:
Study Status:
Phase of Development:
Objectives: The primary objective was to evaluate whether analgesia with oxycodone prolonged release
(PR) tablets (OxyContin® tablets) taken in combination with gabapentin was superior to analgesia with
gabapentin alone.
The secondary objective was to compare the two treatments with respect to sleep quality. Methodology A randomised, double-blind, parallel group comparative study in patients with diabetes
mellitus who had moderate to severe neuropathic pain despite receiving gabapentin. Patients continued
their treatment with gabapentin at a stable frequency and dose and took either oxycodone PR tablets (5,
10, 20 or 40 mg) or placebo oxycodone PR tablets (5, 10, 20 or 40 mg) for a period of up to 12 weeks.
Number of Patients: Planned: 334 patients (167 per treatment group). Randomised: 338 patients.
Completed: 249 patients. Discontinued: 37 in Placebo group (54% of these were due to lack of efficacy);
42 in the Oxycodone PR group (14% of these were due to lack of efficacy).
Indication and Criteria for Inclusion: Male or female adults aged 18 to 75 years established on the
maximum tolerated dose of gabapentin for their neuropathic pain, but still experiencing moderate to severe
pain.
Test Treatment, Dose, and Mode of Administration:
Oxycodone PR tablets (manufactured by Bard Pharmaceuticals Limited) Oral administration, 1 tablet every 12 hours Reference Treatment, Dose, and Mode of Administration:
Placebo tablets to match oxycodone PR tablets (manufactured by Bard Pharmaceuticals Limited) Oral administration, 1 tablet every 12 hours. Duration of Treatment: 12 weeks
Treatment Schedule: At entry into the study, eligible patients were randomly allocated one of the
following treatments (in a ratio of 1:1):
 Oxycodone PR tablets taken 12 hourly.  Placebo oxycodone PR tablets taken 12 hourly. All patients started the study on the lowest dose of medication (oxycodone PR tablets 5 mg, 12 hourly, or placebo oxycodone PR tablets 5 mg, 12 hourly) and continued their treatment with gabapentin. The investigator titrated the patients’ study medication in a stepwise fashion i.e. increased or reduced the medication by one dose level. Dose titration was permitted for the entire duration of the double-blind Phase (12 weeks).
Criteria for Evaluation:
 Patients’ global assessment of pain relief  Short-Form Brief Pain Inventory (SF-BPI)1  Short-Form McGill Pain Questionnaire (SF-MPQ)2 Safety: Safety will be assessed using adverse events, clinical laboratory results, vital signs and physical examinations. Statistical Methods:
All statistical tests were two-tailed at the 5% significance level. No interim analyses were performed. Efficacy variables
The efficacy variables were summarised by treatment group and period/visit for the full analysis population. The primary efficacy endpoint was also summarised for the PP population. The primary efficacy endpoint, mean change in BS-11 pain scores from baseline to the double-blind phase, was summarised as continuous data and analysed using a repeated measures analysis of covariance (ANCOVA) with assessment period as a repeating factor, and baseline scores as a covariate. Country was included as a factor in the model. The estimated mean treatment differences and 95% confidence intervals (CIs) were determined from this model. Mean escape medication use was summarised as continuous data, and analysed using a repeated measures ANCOVA. Quality of sleep, and overall study medication rating were analysed using a Mantel-Haenszel test. The overall estimated mean treatment difference in BPI pain intensity/interference; SF-MPQ total pain, sensory pain, affective pain, VAS and PPI scores and the corresponding 95% CIs were calculated from a repeated measures ANCOVA. Patient resource utilisation data were summarised as continuous data. Safety variables
All safety variables were summarised by treatment group for patients in the safety population. The number and percentage of patients reporting Treatment-Emergent Adverse Events/Adverse Drug Reactions were summarised by system organ class, MedDRA term and phase. Discontinuation details, vital signs and laboratory tests were summarised descriptively. Results:
Efficacy: The BS-11 pain scores provide evidence of a statistically significant ‘treatment by period’
interaction that demonstrated a different response by the two treatments to time and a statistically
significant treatment difference in favour of oxycodone PR (P=0.004). The mean adjusted treatment
difference for assessment Period 6 was 0.69 (Full Analysis population) and 0.87 (Per Protocol population).
The reductions in BS-11 pain scores from baseline were considered to be clinically relevant.
The secondary and exploratory efficacy variables confirmed the beneficial effect of oxycodone PR in subjects with diabetic neuropathy. Safety: 19 patients in the Oxycodone PR group and 18 in the placebo group experienced serious adverse
events during the study. There was one death due to myocardial infarction that was not related to study
drug.
Overall, treatment-emergent adverse events were more frequently reported in patients in the Oxycodone PR group (88%) compared to patients in the Placebo group (71%). The most frequently reported adverse events in the Oxycodone PR group were all recognised opiate-induced adverse events. Importantly, adverse events were not exacerbated by the addition of oxycodone PR to gabapentin therapy. Conclusions: This study provides the first evidence that oxycodone PR added to existing gabapentin
therapy has a beneficial effect on neuropathic pain in patients with diabetes mellitus. The difference is
statistically significant and is greater at the end of the assessment period and the reduction in pain scores
was clinically significant. The evidence seen in the primary and secondary efficacy analysis is further
confirmed by the statistically significant treatment differences seen in the analysis of the BPI pain scores
and the scores from the McGill Pain Questionnaire.
Date of the Report: 21 December 2005

Source: http://napp.co.uk/wp-content/uploads/2013/11/OXY3204-synopsis.pdf