ASTRAZENECA AND MERCK AGREE TO AMEND SECOND OPTION

AstraZeneca today announced that AstraZeneca and Merck have agreed to amend
certain provisions of the agreements relating to the companies’ arrangements in
the United States.

AstraZeneca believes that the amendments provide a greater degree of certainty
to the valuation of the Second Option that is preferable to the previous
arrangements and, barring unforeseen circumstances, the company now intends to
exercise the Second Option in 2014.

The principal areas covered by the amendments are a change in the timing for
AstraZeneca to exercise the Second Option, and agreement on the valuation
methodology for setting certain aspects of the option exercise price.

Under the amended agreement, the companies have agreed that Merck will grant to
AstraZeneca a new Second Option exercisable by AstraZeneca between 1 March 2014
and 30 April 2014, with closing on 30 June 2014. The options exercisable in 2017
or if combined annual sales fall below the minimum amount also remain available
to AstraZeneca.

In addition to this revised timing for the Second Option, the companies have
also reached agreement on the valuation methodology for setting certain
components of the option exercise price for a 2014 exercise. In lieu of third
-party appraisals, this valuation for a 2014 exercise is now a fixed sum of $327
million, based on a shared view by the companies of the forecasts for sales of
Nexium and Prilosec in the US market. The agreed amount payable on 30 June 2014
is subject to a true-up in 2018 that replaces a shared forecast with actual
sales for the period from closing in 2014 to June 2018.

In addition, the exercise price of the Second Option also includes a multiple of
ten times of Merck’s average 1% annual profit allocation in the Partnership for
the three years prior to exercise. AstraZeneca currently expects this amount to
be around $80 million.

The component of the exercise price of the Second Option that includes the net
present value of up to 5% of future US sales of Vimovo, with the precise amount
dependent on an annual sales threshold that has not yet been achieved and the
timing of the option exercise, will continue.

Under the amendments, if AstraZeneca exercises in 2014, Merck’s existing rights
to manufacture Nexium and Prilosec would cease upon closing.

This amended Second Option arrangement has no impact on AstraZeneca’s Core
financial guidance for 2012, which will, in accordance with normal practice, be
reviewed in conjunction with the announcement of the Second Quarter and Half
Year Results on 26 July 2012.

Further information on the AstraZeneca arrangements with Merck, including the
history, and details of the previous termination arrangements completed in March
2008 and in April 2010, can be found in the AstraZeneca 2011 Annual Report and
Form 20-F Information for 2011, pages 181-183.

About AstraZeneca
AstraZeneca is a global, innovation-driven biopharmaceutical business with a
primary focus on the discovery, development and commercialisation of
prescription medicines for gastrointestinal, cardiovascular, neuroscience,
respiratory and inflammation, oncology and infectious disease. AstraZeneca
operates in over 100 countries and its innovative medicines are used by millions
of patients worldwide. For more information please visit: www.astrazeneca.com

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