Pascal Soriot, AstraZeneca chief executive © FT montage / Bloomberg

Shares in AstraZeneca fell on Thursday following a report that its chief executive, Pascal Soriot, was leaving the Anglo-Swedish drugmaker after almost five years to take the top job at Teva Pharmaceutical Industries.

Both companies dismissed the suggestion, in an Israeli newspaper, that Mr Soriot had accepted the job, at a salary almost double that of his predecessor, as “market rumour”, but traders reacted strongly.

AZ’s share price fell more than 4.6 per cent in morning trading on Thursday, recovering slightly to close about 3.5 per cent lower. Teva’s shares had soared almost 7 per cent by late afternoon.

On Friday morning AZ shares fell a further 1.4 per cent.

Analysts and investors noted that if Mr Soriot departed it would be shortly before the expected publication of results from a trial of an immunotherapy drug for lung cancer, which is regarded as important for the company’s long-term future.

In a recent interview with the FT, the chief executive had appeared to play down the likely strength of the first tranche of data from what has become one of the year’s most closely watched trials. He suggested the company might be “lucky” and see strong results at this stage, but that a definitive judgment on the drug’s potential was unlikely until a fuller read out of data next year.

AZ insiders said Mr Soriot was unaware of the strength, or otherwise, of the trial results which were still “blinded”.

When he fended off a takeover bid from Pfizer three years ago, Mr Soriot put at the heart of his defence his ability to revitalise the company’s research and development pipeline. Imfinzi, the drug in the Mystic trial, represents one of its best hopes for replacing revenue lost from patent expiries on one-time blockbuster drugs, with estimated peak annual sales of at least $2.5bn.

According to the unconfirmed details printed in the Israeli financial newspaper, Calcalist, Mr Soriot has accepted the job and is in the final stages of negotiations. The newspaper suggested he would receive a salary almost double that of the previous CEO, Erez Vigodman, as well as a signing bonus of $15m-$20m.

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