Introduction: Off-label prescribing (OLP) may raise serious safety concerns that traditional spontaneous reporting of adverse drug reactions (ADRs) may not identify in a timely manner. In France, the 'Multidisciplinary Consultation Service for Off-Label Prescribing in Addiction Medicine' (CAMTEA) is a proactive regional system established to identify ADRs associated with the OLP of baclofen for alcohol dependence.
Objective: The aim was to demonstrate, using the French pharmacovigilance database (FPVD), that CAMTEA allowed for the reporting of a substantial amount of ADRs, comparable in nature to those provided via spontaneous reporting.
Method: The 2012-2013 FPVD notifications associated with baclofen OLP were extracted. The ten most frequent types of ADRs among 'serious' and 'non-serious' reports were listed. The frequency of each type of ADR was compared between CAMTEA and spontaneous reporting, and the magnitudes of the differences were assessed using standardized differences.
Results: A total of 428 baclofen reports (1043 ADRs) were identified, among which 221 (51.64%) originated from CAMTEA. The ten most frequent ADRs in 'serious' reports were (1) confusion (17.3%), (2) seizures (11.5%), (3) drowsiness/sedation (11.5%), (4) agitation (10.9%), (5) coma (9.6%), (6) hallucinations (7.7%), (7) falls (7.1%), (8) behavioral disorders (5.8%), (9) withdrawal syndrome (5.1%), and (10) space-time disorientation (5.1%). A standardized difference of <0.2 was identified for six out of the ten most frequent 'serious' ADRs, and eight of the ten 'non-serious' ADRs.
Conclusion: A proactive regional pharmacovigilance system could collect a substantial amount of safety data on a specific OLP practice. The profile of the ADRs collected was similar to that seen in the nationwide spontaneous reporting system.