Targin ( Targinact, Targiniq ), a fixed combination of prolonged-release Oxycodone / Naloxone, has received a positive European Commission ( EC ) decision for a new indication, as a second line symptomatic treatment for patients with severe to very severe idiopathic restless legs syndrome ( RLS ), after failure of dopaminergic therapy.
Oxycodone / Naloxone is the first opioid which has been granted a licence in the European Union ( EU ) for the treatment of restless legs syndrome.
This new indication provides a viable treatment option for patients who cannot tolerate the existing available treatments or who are not able to gain the level of symptom relief required.
Up until now, symptomatic treatment of idiopathic restless legs syndrome included mainly dopamine agonists or dopaminergic substances such as L-dopa, however long-term use can lead to worsening of the symptoms in many individuals.
Data published in The Lancet Neurology supports the basis of this new indication approval. Findings from the 12 week double-blind, randomised placebo-controlled trial with a 40 week open-label extension, showed:
A significant improvement in the Mean International RLS Study Group rating scale ( IRLS ) in the prolonged release Oxycodone and Naloxone group versus placebo ( -16.5 vs. -9.4; p less than 0.0001 ) at 12 weeks.
This translates into a significant clinical improvement from very severe at start of treatment to on average mild or moderate at the end of the double-blind phase.
A beneficial effect of treatment with prolonged release Oxycodone and Naloxone at the end of the 40-week open-label extension phase ( mean sum score of 9.7 at week 40 compared to a starting score of 15.4 ), providing evidence of longer term efficacy for prolonged release Oxycodone / Naloxone.
Improvements in the quality and quantity of sleep for patients in the Oxycodone / Naloxone group vs placebo, with fewer RLS symptoms when going to sleep and during the night vs. placebo.
That 42% of patients in the Oxycodone / Naloxone group were considered IRLS remitters at 12 weeks, versus 19% in the placebo group.
Furthermore, at the end of the 40 week extension, 43% of patients were considered remitters, and 22% of remitters ( by International RLS Study Group severity rating scale ) were asymptomatic.
No augmentation was seen over the entire 52 week study period.
An adverse event profile for Oxycodone / Naloxone over the entire study period that was consistent with the safety profile of opioids, with very common side effects ( those occurring in greater than or equal to 1/10 patients ) including gastrointestinal disorders, headache, somnolence, fatigue, pruritus and hyperhidrosis.
Restless legs syndrome, also known as Willis-Ekbom disease, is a neurological disorder characterised by an overwhelming urge to move, usually affecting the legs, patients suffering from RLS may describe feelings of tingling, burning, itching or throbbing, a creepy-crawly feeling or cramping in the legs.
Between 5%-10% of adults in some Western countries are affected by the condition, which mostly occurs during the evening or at night when patients are trying to sleep.
Symptoms occur primarily at night and can increase in severity throughout the night. Moving the legs relieves the discomfort.
Restless legs syndrome is a common cause of insomnia related to problems with sleep initiation and sleep maintenance, un-refreshing sleep, and excessive daytime sleepiness, and it may signify an underlying medical condition. ( Xagena )
Source: Mundipharma, 2015