AstraZeneca plc (AZN) - Get Report shares fell sharply in the opening hour of trading in London Thursday after it was reported that Teva Pharmaceuticals (TEVA) - Get Report was courting the CEO of Britain's second-biggest drugmaker.

Shares dropped the most in nearly two years and were marked 4.5% lower at 8:45 London time and changing hands at 4,949 pence each, trimming their three-month gain to around 5.5%.

Israel-based Teva is expected to name AstraZeneca CEO Pascal Soriot, Reuters reported citing Israeli financial news website Calcalist.

Soriot has apparently met with Teva's search committee and chairman and has agreed to take the job, Calcalist reported Wednesday.

Soriot would be filling the shoes of Erez Vigodman who stepped down in February after a string of costly acquisitions, along with delayed drug launches, sent Teva shares plummeting and led to calls for management and structural changes, including a possible split into separate generic and branded medicine units.

Chief Financial Officer Eyal Desheh also resigned at the end of June.

According to Calcalist Soriot is expected to earn twice as much as Vigodman and receive a bonus upon signing the contract, estimated at about $20 million.

Teva shares were up 4.18% om Tel-Aviv at 11,490 Israeli shekels.