Drugs Xagena
The CHMP, the scientific Committee of the European Medicines Agency ( EMEA ), adopted a negative opinion, recommending the refusal of the marketing authorisation for the medicinal product Ramelteon 4 mg and 8 mg tablets intended for the treatment of primary insomnia in adult patients.
Ramelteon was expected to be used to treat primary insomnia in patients aged 18 years or over. Primary means that the insomnia does not have any identified cause, including other medical, mental or environmental causes.
Ramelteon is a melatonin-receptor agonist. This means that it works by attaching itself to the receptors that melatonin normally attaches itself to.
Melatonin is a naturally occurring hormone that is involved in co-ordinating the bodys sleep cycle by acting on receptors in specific areas of the brain.
Ramelteon was expected to work in the same way as melatonin in promoting sleep.
The effects of Ramelteon were first tested in experimental models before being studied in humans.
The effectiveness of Ramelteon was compared with that of placebo in a total of about 5,400 patients. Most of the studies were carried out in sleep laboratories, but the three main studies in a total of 2,807 patients were carried out in a natural setting ( at home ).
All of the studies except one were short-term studies that lasted five weeks or less. The one long-term study lasted six months, during which patients spent some nights in a sleep laboratory. The main measure of effectiveness was the time taken for the patient to fall asleep.
The CHMP was concerned that Takeda had not demonstrated the effectiveness of Ramelteon, which was measured considering only one aspect of insomnia, the time to fall asleep. In addition, in only one of the three studies in a natural setting there was a difference in time to fall asleep between patients taking Ramelteon and those taking placebo, and this difference was considered too small to be relevant. When other aspects of sleep were considered, Ramelteon did not have any effect.
The Committee was also concerned that Takeda had not demonstrated the long-term effectiveness of Ramelteon.
At that point in time, the CHMP was of the opinion that the benefits of Ramelteon in the treatment of primary insomnia did not outweigh its risks. Hence, the CHMP recommended that Ramelteon be refused marketing authorisation.
Ramelteon is marketed as Rozerem by Takeda Pharmaceuticals North America.
Source: EMEA, 2008
XagenaHeadlines_2008
