The study is divided into four phases: Phase A, B, C and D. All patients who have completed Phase A and for whom the investigator considers further participation to be safe shall begin Phase B. Phases C and D run in parallel, so that patients who have completed Phase B and for whom the investigator considers further participation to be safe can be assigned to one of the two phases.~Phases A and D follow a double-blind, placebo-controlled design, while Phase B and C have an open-label design.~The main goal of Phase A is to demonstrate the efficacy of VER-01 compared to placebo. In Phase B and C the main goal is the investigation of long-term safety of VER-01. In Phase D the primary objective is to demonstrate the maintenance of efficacy of VER-01 on a placebo-controlled basis.~The potential for dependence and abuse will be analyzed in all Phases (A,B,C,D), while the effect of abrupt drug withdrawal of VER-01 will be analyzed in Phase C and D.
Analysis of the efficacy, maintenance of efficacy, long-term safety, and investigation of the potential for dependence and abuse and the effect of abrupt drug withdrawal of VER-01 in the treatment of patients with chronic non-specific low back pain when drug treatment is indicated and previous optimised treatments with non-opioid analgesics have not led to sufficient pain relief or were unsuitable due to contraindications or intolerance.