The company was founded in 1999 through the merger of the Swedish Astra AB and the British Zeneca Group[7][8] (itself formed by the demerger of the pharmaceutical operations of Imperial Chemical Industries in 1993).

It has its research and development concentrated in three strategic centres: Cambridge, United Kingdom; Gothenburg, Sweden[10][11] and Gaithersburg in Maryland, U.S.[12] AstraZeneca traces its earliest corporate history to 1913, when Astra AB was formed by a large group of doctors and apothecaries in Södertälje.

[23] In February 2007, AstraZeneca agreed to buy Arrow Therapeutics, a company focused on the discovery and development of anti-viral therapies, for US$150 million.

[27] In December 2009, AstraZeneca acquired Novexel Corp, an antibiotics discovery company formed in 2004 as a spin-off of the Sanofi-Aventis anti-infectives division.

[32] In June 2012, AstraZeneca and Bristol Myers Squibb announced a two-stage deal for the joint acquisition of the biotechnology company Amylin Pharmaceuticals.

[42] In September 2014, the company joined forces with Eli Lilly in developing and commercialising its candidate BACE inhibitor – AZD3292 – used for the treatment of Alzheimer's disease; this deal was projected to yield up to US$500 million AstraZeneca.

[45] In December, the company received accelerated FDA approval for Olaparib in the treatment of women with advanced ovarian cancer who have a BRCA genetic mutation.

[46] In February 2015, AstraZeneca announced it would acquire the US and Canadian rights to Actavis's branded respiratory drug business for an initial sum of US$600 million.

[48] The company also announced its plan to spend US$40 million creating a new subsidiary focused on small molecule anti-infectives – primarily in the research of the gyrase inhibitor, AZD0914, which was then in Phase II testing for the treatment of gonorrhea.

[51] In April, the firm announced a number of collaborations worth an estimated US$1.8 billion; first, to develop and commercialise MEDI4736, with Celgene, for use against non-Hodgkin’s lymphoma, myelodysplastic syndromes, and multiple myeloma with AstraZeneca receiving US$450 million.

[56] In August, the company announced it had acquired the global rights to develop and commercialise Heptares Therapeutics' drug candidate HTL-1071, which focuses on blocking the adenosine A2A receptor, in a deal worth up to US$510 million.

[61] In December, the company announced its intention to acquire the respiratory portfolio of Takeda Pharmaceutical – namely Alvesco and Omnaris – for US$575 million[62] A day later, the company announced it had taken a 55% majority stake in Acerta for US$4 billion; the transaction included commercial rights to Acerta's irreversible oral Bruton's tyrosine kinase inhibitor, acalabrutinib (ACP-196), which under development at that time.

[65] Two months later, the firm's chairman Leif Johansson planned in taking the "first steps" in moving its research and manufacturing operations away from the United Kingdom, if there is a hard Brexit.

[72][73] In October 2019, AstraZeneca announced it would sell the global commercial rights for its drug to treat acid reflux to German pharmaceutical company Cheplapharm Arzneimittel GmbH for as much as US$276 million.

[74][75] In February 2020, AstraZeneca agreed to sublicense its global rights (except Europe, Canada and Israel) to the drug Movantik, to Redhill Biopharma.

[81] On 27 December 2020, AstraZeneca CEO Pascal Soriot said that they have “figured out the winning formula” with their two-dose system with the Oxford University’s COVID-19 vaccine.

[86][87] In October 2021, the company, through Alexion, acquired Caelum Biosciences and its monoclonal treatment (CAEL-101) for light chain (AL) amyloidosis for up to $500 million.

[96] Later that month, AstraZeneca agreed to acquire clinical-stage biopharmaceutical developer of cell therapies for the treatment of cancer and autoimmune diseases, Gracell Biotechnologies, in a deal valued at up to $1.2 billion.

Clinical trials showed Enhertu extended patients' lives by five months compared to chemotherapy, but Nice and the companies could not agree on a new price.

[104] The following is an illustration of the company's major mergers and acquisitions and historical predecessors:[105] AstraZeneca develops, manufactures and sells pharmaceutical and biotechnology products to treat disorders in the oncology, cardiovascular, gastrointestinal, infection, neuroscience, respiratory and inflammation areas.

This facility, known as the Discovery Centre, was designed by Swiss architecture firm Herzog & de Meuron[111] and officially opened by Prince Charles on the 23 November 2021.

[122] The company's non-executive Board directors are Philip Broadley, Euan Ashley, Michel Demaré, Deborah DiSanzo, Diana Layfield, Sheri McCoy, Tony Mok, Nazneen Rahman, Andreas Rummelt, and Marcus Wallenberg.

[124] AstraZeneca is a member of the Personalized Medicine Coalition, a medical research advocacy group that lobbies on behalf of the pharmaceutical industry.

"[133] On 4 February 1998, Astra USA sued Lars Bildman, its former president and chief executive officer, seeking US$15 million for defrauding the company.

Astra's lawsuit alleged Bildman sexually harassed and intimidated employees, used company funds for yachts and sex workers, destroyed documents and records, and concocted: "tales of conspiracy involving ex-KGB agents and competitors.

[137][135] In February 1998, AstraZenaca's U.S. affiliate Astra U.S.A. agreed to a $10 million settlement after an Equal Employment Opportunity Commission investigation which started in May 1996 found that sexual harassment against female employees.

2009), applying New York's faithless servant doctrine, the court held that a company's employee who had engaged in financial misdeeds and sexual harassment must "forfeit all of his salary and bonuses for the period of disloyalty".

[141] In 2004, University of Minnesota research participant Dan Markingson took his own life while enrolled in an industry-sponsored pharmaceutical trial comparing three FDA-approved atypical antipsychotics: Seroquel (quetiapine), Zyprexa (olanzapine), and Risperdal (risperidone).

Among the allegations, former AstraZeneca employees are accused of falsifying genetic tests to secure reimbursement for the company’s lung cancer drug, Tagrisso.

[159] Several current and former company executives are also being investigated for potentially breaching data privacy laws and for the suspected illegal importation of certain cancer drugs – likely including Enhertu, Imfinzi and Imjudo – from Hong Kong.