Patent expiries will stem growth of antidepressants market

Global sales of antidepressants will experience a modest 4% annual growth rate over the 2006-2016 period, as patent expiries and the introduction of novel agents erode the turnover of market-leading drugs, according to a new report from Decision Resources.

The Pharmacor report, titled Outlook for Antidepressants, 2006-2016: Will Novel Agents Surprise the Market? finds that the patent expiries of market- leading drugs in the monoaminergic class - including Pfizer's Zoloft (sertraline), GlaxoSmithKline's Wellbutrin (bupropion), Forest/Lundbeck's Lexapro (escitalopram) and Wyeth's Effexor (venlafaxine) - will play a key role in constraining market growth between 2010 and 2016 in the USA, Japan, Germany, France, Spain, Italy and the UK. Additionally, the arrival of next-generation monoaminergic drugs, including that of the triple reuptake inhibitors in 2010, will not sustain the market's value and will not meet the need for more effective agents for the treatment depression and anxiety, says DR.

According to the report, the arrival of four classes of novel non-monoaminergic agents, including drugs from GSK and Servier/Novartis, will account for approximately 30% of sales in 2016. GSK's paroxetine/vestipitant and Servier/Novartis' melatonin agonist agomelatine will be the only non-monoaminergic drugs to compete for first-line use in primary care and will be used as adjuncts to monoaminergic antidepressants in refractory patients and other subgroups.