CNS Drug Discoveries: Parkinson's Disease Chapter

Parkinson's disease

In 2007, approximately US$3.6 billion was spent on the symptomatic treatment of Parkinson's disease (PD). Although this neurodegenerative disease affects approximately 1% of the population its prevalence increases with age, thus it is likely to become more commonplace due to patient demographics and become a greater burden to healthcare payers.

PD patients are treated with a cocktail of drugs which are adapted to the patients' needs as the disease progresses. There is no cure and current therapies are relatively effective at treating the symptoms in the early stages but less so in advanced PD, and there remain significant side effects.

Whilst generic levodopa remains the cornerstone of treatment and is widely available relatively cheaply, its chronic use is not necessarily limited by budget, but by its long-term effectiveness. Hence, the more costly dopamine agonists have gained utility in the treatment of the early stage of the disease helping to spare levodopa treatment.

However, over the next six years many of the leading dopamine agonists face patent expiration, enabling generics to become more freely available. Meanwhile some companies have new improved dopamine agonists in their pipelines such as Solvay's pardoprunox or more potent monoamine oxidase inhibitors such as Merck KGaA/Newron's safinamide.

Some companies have picked up the gauntlet and run to develop new disease-modifying agents which could revolutionise the way advanced PD is treated. For example, Bayer's high-risk, high-reward approach to developing spheramine is a novel cell therapy that may halt the progression of PD.

Key PD questions answered include:

• What percentage of the treatable population for PD has been diagnosed in Europe, US and Japan?
• Which PD products will face generic challenges by 2014?
• What are the commercial prospects for Bayer's revolutionary disease-modifying agent spheramine?
• By 2014, Boehringer Ingelheim and GSK will have lost considerable PD market share - to whom and what products will make the difference?

Key products analysed and forecast

• ApokynBritannia/Ipsen
• AzilectLundbeck/Teva Pharmaceuticals
• Comtan franchiseNovartis/Orion
• IstradefyllineKyowa Hakko
• MirapexBoehringer Ingelheim
• NeuproUCB
• Pardoprunox Solvay
• RequipGlaxoSmithKline
• SafinamideMerck KGaA/Newron
• SpheramineBayer/Titan Pharmaceuticals