European Zytiga Sales Increase Whilst US Sales Decline

The latest sales figures for Zytiga show that sales appear to be remaining static going from $ 265 M in Q3 to $ 264 M in Q4, but these figures conceal two opposite trends that are affecting sales:

- A decrease in US sales down from $ 136 M in Q3 to $ 114M in Q4
= reduction of $ 22 M.

- An increase in the rest of the world (ROW) sales from $ 129 M in Q3 to $ 150 M in Q4
= increase of $ 21 M.

The ROW sales increase and US sales decrease cancel out to give no overall increase in Q4 sales.

The ROW sales figures are mainly contributed by an increase in European sales where Zytiga is now available on the National Health Services of a number of European countries such as the UK and Germany.

The decrease in US sales of Zytiga is largely due to competition from the newly licensed rival drug Xtandi. Without the market presence of Xtandi the US sales of Zytiga would have been expected to continue increasing as it has been doing, but this is the first time US Zytiga sales have declined representing market share taken by Xtandi. However this decrease will probably be short lived as Xtandi's shortfalls and lack of efficacy are revealed in clinical practise. There are already some oncologist who have tried Xtandi and are now switching thier patients back to Zytiga.

Further evidence for the impact of Xtandi comes from the fact that Xtandi is only FDA approved for use in the USA and has not yet received European approval which would explain why the European sales figures have been unaffected and continue to grow.