European benchmarks slid Thursday despite a stream of solid corporate earnings reports as losses at several major constituents sank markets. 

The FTSE 100 pared much of its loss during noon trading to be quoted just 0.05% lower, at 7,449. This is while the CAC 40 fell by 0.15% to 5,182 in Paris and the DAX index slumped by 0.74% to 12,214 in Frankfurt. In Southern Europe, stocks were more mixed, with the IBEX posting a 0.08% loss and the FTSE MIB showing a gain of nearly 0.20%.

London's FTSE suffered throughout much of the day after Astrazeneca (AZN) - Get Report  shares saw their worst session on record. The drugmaker told investors that its Imfinzi-tremelimumab combination did not meet its primary endpoint of progression-free survival for the treatment of lung cancer sufferers when compared with chemotherapy.

The result meant analysts shaving around 15% off of their forecasts for revenue at Astra over the coming years after a successful trial had become baked into the consensus. 

Still, with the shares now down more than 15%, some have speculated that with question marks hovering over the company's future top line and given the lower level of the shares, Astra could soon find itself in the crosshairs of a predator once again.

The loss for Astrazeneca was partially offset by strong gains at other large index constituents such as Diageo (DEO) - Get Report and Rentokil (RTOKY) , which were up 6% and 5%, respectively. 

Diageo beat expectations and raised its three-year margin improvement target to 175 basis points, up from an additional 100 basis points previously. Rentokil reported a modestly better-than-expected set of results for the half-year and said it will look to do more M&A over the coming quarters. 

In France, Schneider Electric (SBGSF) topped the CAC 40 after saying it will buy the automated transfer switch business of Emerson Electric (EMR) - Get Report  in a $1.25 billion deal that makes it a globally dominant force in the ATS market. The shares rose 3.5% in response to the news, which was warmly received by the analyst community. 

Airbus (EADSY) and Accor Hotels were weights around the ankles of the CAC 40 index with losses of 2% or more each during noon trading. 

Over in Frankfurt, the DAX index was weighed down by heavy losses at Deutsche Bank (DB) - Get Report after it said a weak second-quarter means that it will report lower revenue for 2017 overall. The embattled lender saw its shares fall more than 6% during the session.

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