Efficacy of the Combination of Ibuprofen and Paracetamol in Acute Non-specific Low Back Pain

Inclusion Criteria: * Male and female patients of any ethnic origin between 18 and 64 years of age (limits included). * Patients with uncomplicated and localized acute low back pain or acute exacerbation of chronic low back pain (not radiating below the gluteal fold), with moderate/severe pain at baseline. Minimum VAS score ≥ 40 mm at screening visit. * Women of childbearing potential and women with no menses for a period \< 12 months must have a negative pregnancy test at Visit 0 and have to agree not to start a pregnancy from the signature of the informed consent up to the Final Visit/Visit 2, using an appropriate birth control method such as combined oestrogen-progestin containing hormonal contraceptives (e.g., oral, injectable, transdermal), progestin-only hormonal contraceptives (e.g., oral, injectable, implantable), intrauterine device (IUD) or Intrauterine hormone-releasing System (IUS) in combination with male condom, bilateral tubal occlusion, vasectomised partner, sexual abstinence. The following definitions will be considered: * Woman of childbearing potential (WOCBP): i.e., fertile, following menarche and until becoming post-menopausal, unless permanently sterile. Permanent sterilization methods include hysterectomy, bilateral salpingectomy and bilateral oophorectomy. * A postmenopausal state is defined as no menses for 12 months without an alternative medical cause. * Patients legally capable of giving their consent to participate in the study and available to sign and date the written informed consent. Exclusion Criteria: * Known hypersensitivity or allergy to the active ingredients and/or to any component of the study medications. * Patients with rare hereditary problems of galactose intolerance, total lactase deficiency or glucose-galactose malabsorption * Lactating and pregnant women. * Clinically significant abnormalities on physical examination, vital signs or laboratory tests at Visit 0 which in the opinion of the Investigator could interfere with the study procedures or endpoints evaluation. * Suspicious or confirmed COVID-19 infection at time of screening visit. * History of cervical, thoracic, or lumbosacral pain for ≥75% of the time in the last year, or of any other Low Back Pain episode in the last 3 months that required pharmacological treatment with an opioid analgesic. * Patients with: * serious spinal pathology; spinal surgery in the year prior to screening or history of more than one spinal surgery; history of severe lumbar spinal stenosis; ankylosing spondylitis; lumbosciatalgia; herniated disc or radiculopathy; severe arthritis and osteoporosis; muscular diseases, such as myositis, poliomyelitis, muscular dystrophy and myotonia; fibromyalgia; myasthenia grave; fracture or recent history of violent trauma of the back; structural deformity of the back; * history of hypersensitivity to aspirin or any other non-steroidal anti-inflammatory drugs; suspicion of inflammatory, infective or neoplastic cause of pain; non- specific back symptoms related to abdominal, pelvic or thoracic pathology sensory and/or motor deficits in lower extremities; * history of gastroduodenal ulcer or bleeding; * history of severe cardiac, hepatic or renal insufficiency; * current anticoagulant therapy; * previous treatment with anticoagulants in the seven days before the screening visit; * concomitant use of physical or alternative therapies to treat current episode of pain; * local steroid injection for any reasons within previous 30 days; * alcohol or drug-addition or abuse; * cancer, not in remission or in remission less than 1 year; * active influenza or other viral syndrome; immunosuppression; systematically unwell; unexplained significant weight loss; * widespread neurological symptoms (including cauda equina syndrome) or any brain disease; ever suffered from any brain damage or have been in a coma; epilepsy or seizure; * active or suspected oesophageal, gastric, pyloric channel, or duodenal ulceration, or bleeding in the last 30 days; * blood-formation disturbance; * renal and/or hepatic failure; * acute hepatitis; * acetylsalicylic acid-triggered asthma; * history of asthma; * glucose-6-phosphate dehydrogenase-deficient patients; glutathione deficiency, dehydration, chronic malnutrition; anaemia.