Takeda Pharmaceutical Co. shares on Tuesday fell their farthest in 20 years in Tokyo trading over concern one of its most promising experimental medicines will be delayed.
Japan's largest drugmaker slumped as much as 12 percent, or ¥1,000, the maximum allowed by the Tokyo Stock Exchange, to ¥7,060 after analysts cut their ratings on the shares, citing the delay.
The Osaka-based company said late Monday it is reviewing development of the cholesterol drug TAK-475 after it was linked to higher levels of an enzyme that may indicate liver damage.
U.S. drug regulators requested more clinical data on TAK-475 and recommended that studies using higher doses be suspended, Takeda said. The extra tests may delay approval of the medicine, one of three Takeda has in the final stage of patient studies, and frustrate attempts to find a replacement for the Actos diabetes treatment before its patent expires in four years.
"TAK-475 may not reach the market," said Hirohisa Shimura, an equities analyst at UBS Securities Japan Ltd.
The drugmaker hasn't released a product in the U.S. since the sleeping pill Rozerem in September 2005. Analysts predict Takeda's sales will slump once Actos faces generic competition. The world's best-selling diabetes treatment accounted for 29 percent of its revenue in the three months to June 30.
Delays developing TAK-475 "will make it difficult for Takeda to define its growth strategy after the Actos patent expires," UBS's Shimura said.
The U.S. Food and Drug Administration's request was prompted by increases in the enzyme transaminase in some patients taking the higher dose.