CNS Drug Discoveries: Schizophrenia Chapter

Schizophrenia

The antipsychotic market generated global sales of US$19.6 billion, accounting for 21% of global CNS sales in 2007. While atypical antipsychotics now account for over 80% of global sales, concerns over safety are leading to a slow down in growth.

The market is ready for the launch of the third-generation atypical antipsychotics which may offer improved tolerability and may not be associated with extrapyramidal symptoms, cardiotoxicity, weight gain or detrimental metabolic changes. Two products have recently been launched, with four in late-stage clinical development: these could be tomorrow's leading brands if they have improved tolerability and safety profiles.

Meanwhile, companies which market today's leading brands continue to optimise their drugs' life-cycles pursuing new formulations (intramuscular, slow release) to aid compliance, new indications (major depression, anxiety disorders, autism, maintenance of bipolar disorder) and to initiate additional Phase IV trials to optimise and educate the community regarding the courses of treatment.

Importantly, many of these products have been available since the 1990s and their market exclusivity is running out. All the leading brands face patent expiry (in the US) by 2014, with the first generic, risperidone, in mid-2008.

Innovation within the market has been limited, although a number of products that are in Phase II development target new pathways to treat cognitive impairment associated with schizophrenia (CIAS) through the modulation of neurokinin-3 receptor or 5-HT6 receptors.

Key schizophrenia questions answered include:

• What % of the market will be taken by generics in 2014?
• What underpins the US$1.5 billion sales estimate for J&J's Invega?
• There are 19 schizophrenia treatments in Phase II - what are they and who is developing them?
• As Lilly, J&J and AstraZeneca lose market share, which companies will emerge as players in this valuable sector?

Key products analysed and forecast

• AbilifyBristol-Myers Squibb/Otsuka
• AsenapineSchering-Plough
• BifeprunoxLundbeck/Solvay
• FanaptaVanda Pharmaceuticals
• Geodon/ZeldoxPfizer
• InvegaJohnson & Johnson
• LonasenDainippon Sumitomo Pharma
• LurisadoneDainippon Sumitomo Pharma
• RisperdalJohnson & Johnson
• SeroquelAstraZeneca
• ZyprexaEli Lilly