Double-blind, randomised, placebo-controlled prospective multicenter phase III trial to assess the efficacy and safety of topical propyl nicotinate (Elacur® hot) in adjuvant treatment of chronic non-specific low back pain

INTERVENTION: Intervention 1: Verum: 9 cm of cream will be topically applied twice daily to the aching back area for 14 consecutive days Intervention 2: Placebo: 9 cm of cream will be topically applied twice daily to the aching back area for 14 consecutive days CONDITION: chronic non‐specific low back pain M54.5 ‐ Low back pain PRIMARY OUTCOME: Main target parameter will be the Modified Arhus Rating Scale for placebo and verum on day 14. SECONDARY OUTCOME: Reduction of chronic non‐specific low back pain, measured by subjective back pain on a 100mm long Visual Analogue Scale (VAS). Impairment of movement, disability questionnaire, global assessment of efficacy by patient and investigator INCLUSION CRITERIA: 1. caucasian origin 2. chronic non‐specific low back pain (lumbar region): subjective back pain of at least 40 mm but not more than 80 mm on a 100 mm long Visual Analogue Scale (VAS). 3. duration of low back pain for at least 3 months 4. no history of drug‐ and alcohol abuse 5. no current or previous participation in another clinical trial in the last 4 weeks 6. concurrent therapy which could interact with the study medication had to be discontinued at appropriate periods before enrollment: the evening before treatment: physical treatment 30h before treatment: Paracetamol 7 days before treatment: Topical medication, muscle relaxants, dose change or start of antihistamines. NSAIDs 8 days before treatment: for Sulindac, Azapropazon, Etoricoxib, Meloxicam, Oxyphenbutazon 17 days before entry: Piroxicam 30 days before treatment for Tenoxicam, Phenylbutazon. four weeks before treatment: systemic opiates and their derivatives, surgic