[2-week efficacy and tolerability of flupirtine MR and diclofenac in patients with acute low/back pain--results of a post-hoc subgroup analysis of patient-level data from four non-interventional studies].

BACKGROUND: Current restrictions in use of flupirtine-containing medicines for a maximum of 14 days endorsed by the European Medicines Agency were followed by uncertainty/ambiguity of its analgesic efficacy for the treatment of acute low/back pain.
METHODS: Post-hoc selection of patient-level data from non-interventional studies with flupirtine MR and diclofenac with respect to patient age (> or = 18 years), duration of treatment (14 +/- 2 days), indication (acute/subacute low/back pain) and first-line use. Primary endpoint: average 24-hr. pain intensity; secondary endpoints: pain-related disabilities in daily life, 30/50/70% response with respect to pain and pain-related restrictions, frequency of untoward side effects/treatment emergent adverse events.
RESULTS: 318/31 patients treated with flupirtine MR/diclofenac fulfilled the inclusion criteria for this subgroup analysis. Starting from comparable demographic and baseline characteristics both treatments were followed by significant effects (p < 0.001). Subgroup comparisons revealed superior effects for flupirtine MR vs. diclofenac for pain relief (p = 0.001), improvement of pain-related restrictions in daily life (p = 0.023), and gastrointestinal/overall tolerability (p < 0.001).
CONCLUSIONS: Even for short-term use in patients suffering from muscle-related acute low/back pain, flupirtine MR is superior effective and tolerated compared with the nsaid diclofenac.