Eli Lilly’s top-selling drug, the antipsychotic Zyprexa (olanzapine), could face generic competition earlier than expected, according to independent market analysis company Datamonitor.
Zyprexa is the leading drug in the antipsychotic category, racking up sales of $4.1 billion dollars in 2003 and with an impressive market share of 39.3% in the seven main pharmaceutical markets (the US, France, Germany, Italy, Japan, Spain and the UK). But while Lilly is already facing a patent challenge to Zyprexa in the US [[03/03/04b]], the franchise could also be hit by patent expirations on two blockbuster competitors – Johnson & Johnson’s Risperdal (risperidone) and AstraZeneca’s Seroquel (quetiapine), in 2006 and 2007, respectively.
At stake is a share of the $10.4 billion dollar market for antipsychotic drugs, which is growing at around 24% a year, according to Datamonitor central nervous system analyst Alistair Sinclair.
2004 has been a bad year for Zyprexa, with fourth quarter revenues down by 5% from the year-ago quarter to $1.1 billion, while US sales of the drug fell by 19% over the previous quarter [[27/01/05a]].
In its own patent battles, Lilly’s trial proceedings ended in February 2004, but a final verdict has still yet to be given. “Datamonitor expects a judge’s decision during the current financial quarter, although a delay of this length has to have a reason, and must continue to worry Lilly,” Sinclair says. “Whatever the outcome of patent litigation, revenues from Zyprexa are forecast to continue to decline as Lilly also faces numerous lawsuits in the US stemming from diabetes and other alleged side effects from Zyprexa” [[22/03/04f]].