Eli Lilly Canada recently announced that Health Canada has approved Cymbalta® (duloxetine HCl) for the management of chronic low back pain (CLBP).
The approval is based on the results of two randomized, double-blind, 12-13 week, placebo-controlled studies in 637 adult patients with a clinical diagnosis of chronic low back pain with pain present on most days for at least 6 months and no sign of radiculopathy or spinal stenosis.
The primary efficacy endpoint in both studies was a reduction in pain severity as measured by the Brief Pain Inventory (PBI) 24-hour average pain rating on the 11-point Likert scale (0 = no pain; 10 = worst possible pain). In both studies, patients taking Cymbalta 60 mg once daily experienced significantly greater pain reduction compared to placebo. In addition, some patients reported pain reduction as early as one week into the trial after starting the 60 mg dose, which continued throughout the study.
Cymbalta has been evaluated for safety in 698 patients with chronic low back pain The most common side effects reported in the two studies included nausea, insomnia, somnolence, constipation, dry mouth, fatigue and dizziness.
Cymbalta is a potent and balanced serotonin and norepinephrine reuptake inhibitor (SNRI), which targets two chemical messengers in the brain believed to play a role in sensitivity to pain – serotonin and norepinephrine. While the mechanism of action of duloxetine in humans is not fully known, scientists believe its effect on pain perception is due to increasing the activity of serotonin and norepinephrine in the central nervous system.
Cymbalta is now indicated in Canada for three distinct pain conditions: chronic low back pain, neuropathic pain associated with diabetic peripheral neuropathy and fibromyalgia. It is also indicated in Canada for the symptomatic relief of major depressive disorder (MDD) and generalized anxiety disorder (GAD).
Duloxetine is contraindicated in patients who are allergic to it, who have liver disease resulting in hepatic impairment, who are taking a monoamine oxidase inhibitor (MAOI) including linezolid and methylene blue, thiorazidine, potent CYP1A2 inhibitors (eg fluvoxamine), and some guinolone antibiotics (eg ciprofloxacin or enoxacine), who have uncontrolled narrow glaucoma, or who have severe kidney disease.
Eli Lilly is a leading innovation-driven corporation, renowned for developing a growing portfolio of first-in-class and best-in-class pharmaceutical products by applying the latest research from its own worldwide laboratories and from collaborations with eminent scientific organizations. Headquartered in Indianapolis, Indiana, Lilly provides answers – through medicines and information – for some of the world's most urgent medical needs. Eli Lilly Canada, headquartered in Toronto, Ontario, employs close to 500 people across the country.