SC TO-C

UNITED STATES SECURITIES AND EXCHANGE COMMISSION 

Washington, D.C. 20549 

________________

SCHEDULE TO

Tender Offer Statement under Section 14(d)(1) or 13(e)(1) of 

the Securities Exchange Act of 1934

ZS Pharma, Inc. 

(Name of Subject Company)

ZENECA, INC.

ZANZIBAR ACQUISITION CORP.

(Names of Filing Persons — Offeror)

Common Stock, Par Value $0.001 Per Share 

(Title of Class of Securities)

________________

98979G 105 

(Cusip Number of Class of Securities)

Adiah Ferron Reid 

1800 Concord Pike 

Wilmington, DE 19850-5437 

Telephone: (302) 886-3000 

(Name, Address and Telephone Number of Person Authorized to Receive Notices 

and Communications on Behalf of Filing Persons)

Copies to:

Marc O. Williams

 Brian Wolfe 

Davis Polk & Wardwell LLP

 450 Lexington Avenue

 New York, New York 10017

 Telephone: (212) 450-4000

CALCULATION OF FILING FEE

Transaction Valuation*	Amount of Filing Fee*
N/A	N/A

* A filing fee is not required in connection with this filing as it relates solely to preliminary communications made before the commencement of a tender offer.

£ Check box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

Amount Previously Paid:	Not applicable.	Filing Party:	Not applicable.
Form or Registration No.:	Not applicable.	Date Filed:	Not applicable.

R Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

R third-party tender offer subject to Rule 14d-1.

£ issuer tender offer subject to Rule 13e-4.

£ going-private transaction subject to Rule 13e-3.

£ amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer. ☐

Exhibit No. Description 

99.1 Press release issued by AstraZeneca plc dated November 6, 2015

99.2 Email sent by Pascal Soriot, CEO of AstraZeneca plc, to ZS Pharma, Inc. employees dated November 6, 2015

99.3 Investor Relations presentation regarding the acquisition of ZS Pharma, Inc. dated November 6, 2015

99.4 Key messages and Q&A regarding acquisition of ZS Pharma, Inc. dated November 6, 2015

EX-99.1

Exhibit 99.1

News Release

AstraZeneca STRENGTHENs CARDIOVASCULAR AND METABOLIC DISEASE PORTFOLIO with ACQUIsition of ZS PHArMA

AstraZeneca to acquire ZS Pharma for $90 per share

Acquisition includes potential best-in-class hyperkalaemia treatment currently under US FDA regulatory review

Acquisition expected to contribute Product Sales from 2016 and benefit AstraZeneca’s return to growth strategy

06 November 2015

AstraZeneca announced today that it has entered into a definitive agreement to acquire ZS Pharma (NASDAQ: ZSPH), a biopharmaceutical company based in San Mateo, California. ZS Pharma uses its proprietary ion-trap technology to develop novel treatments for hyperkalaemia (high potassium levels), a serious condition of elevated potassium in the bloodstream, typically associated with chronic kidney disease (CKD) and chronic heart failure (CHF).

The transaction will give AstraZeneca access to the potassium-binding compound ZS-9, a potential best-in-class treatment for hyperkalaemia, a condition associated with increased mortality in CKD and CHF. ZS-9 is under regulatory review by the US Food and Drug Administration with a Prescription Drug User Fee Act goal date of 26 May 2016. A submission for European Marketing Application Authorisation is planned by the end of 2015. Current estimates for global peak year sales of ZS-9 exceed $1 billion.

The acquisition continues AstraZeneca’s track record of targeted business development with a focus on three main therapy areas. ZS Pharma represents a strong fit with AstraZeneca’s pipeline and portfolio in Cardiovascular & Metabolic Disease, one of the company’s three main therapy areas. AstraZeneca’s strategy focuses on reducing morbidity, mortality and organ damage by addressing multiple risk factors across cardiovascular disease, diabetes and chronic kidney disease. ZS-9 complements the company’s increasing focus on CKD and CHF, including the investigational medicine roxadustat, which is currently in Phase III development for patients with anaemia associated with CKD, as well as its leading diabetes portfolio.

Pascal Soriot, Chief Executive Officer of AstraZeneca, said: “Hyperkalaemia can be a life-threatening condition for patients with chronic kidney disease and chronic heart failure, however the risk is underappreciated and prevalence is increasing. This acquisition complements our strategic focus on Cardiovascular and Metabolic Disease by adding a potential best-in-class treatment to our portfolio of innovative medicines. We look forward to welcoming the ZS Pharma team to AstraZeneca.”

Under the terms of the agreement, AstraZeneca will acquire all of the outstanding capital stock of ZS Pharma for $90 per share in an all-cash transaction, or approximately $2.7 billion in aggregate transaction value.

AstraZeneca · 2 Kingdom Street · London · W2 6BD
T: +44 20 7604 8000 · F: +44 20 7604 8270 · astrazeneca.com AstraZeneca PLC
No. 2723534, Registered Office,
2 Kingdom Street, London W2 6BD

News Release

Upon completion, ZS Pharma, which has around 200 employees across three sites in California, Texas and Colorado, will become a wholly owned subsidiary of AstraZeneca. The transaction does not impact AstraZeneca’s financial guidance for 2015. It is expected to generate Product Sales from 2016, with minimal earnings dilution over 2016 and 2017, becoming accretive to AstraZeneca’s core earnings from 2018.

Robert Alexander, Chief Executive Officer, ZS Pharma, said: “This agreement will allow us to maximize the potential of ZS-9, drawing on AstraZeneca’s long-standing expertise in developing and commercializing medicines for cardiovascular and metabolic diseases. We look forward to joining AstraZeneca and to working together to bring this important treatment for hyperkalaemia to the global market, helping to meet an important unmet medical need for patients.”

Terms of the acquisition

The acquisition is structured as an all-cash tender offer for all outstanding shares of ZS Pharma common stock at a price of $90 per share, followed by a merger in which each remaining untendered share of ZS Pharma common stock would be converted into the same $90 cash per share consideration as in the tender offer.

Under the terms of the merger agreement, AstraZeneca will commence a tender offer to acquire all outstanding shares of ZS Pharma’s common stock. The Board of Directors of ZS Pharma has unanimously approved the terms of the agreement.

Subject to customary conditions, including the tender of a majority of the outstanding ZS Pharma shares and the expiration or earlier termination of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, the transaction is expected to close by the end of 2015. The transaction is not subject to a financing condition.

Conference call for investors and analysts

AstraZeneca will host a conference call for investors and analysts at 14:00 GMT / 09:00 EST on 6 November 2015. A presentation will be available for download from the Investor Relations section of astrazeneca.com (Our company > Investor Relations) before the conference call starts.

Telephone dial-in details for investors and analysts:

UK	08003767922
Sweden	020792102
United States	18669661396
International back-up	+44 (0) 2071 928000

ID code: 73006905.You must quote this number to get on the call.

Listen-only dial-in details for media:

UK	08006945707
Sweden	0200883084
United States	18662540808
International back-up	+44 (0) 1452 541003

ID code: 73081105.You must quote this number to get on the call.

Page 2/5

News Release

– ENDS –

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

SOME OF THE STATEMENTS CONTAINED IN THIS ANNOUNCEMENT ARE FORWARD-LOOKING STATEMENTS, INCLUDING STATEMENTS REGARDING THE EXPECTED CONSUMMATION OF THE ACQUISITION, WHICH INVOLVES A NUMBER OF RISKS AND UNCERTAINTIES, INCLUDING THE SATISFACTION OF CLOSING CONDITIONS FOR THE ACQUISITION, SUCH AS REGULATORY APPROVAL FOR THE TRANSACTION, THE TENDER OF A MAJORITY OF THE OUTSTANDING SHARES OF COMMON STOCK OF ZS PHARMA, THE POSSIBILITY THAT THE TRANSACTION WILL NOT BE COMPLETED AND OTHER RISKS AND UNCERTAINTIES DISCUSSED IN ZS PHARMA’S PUBLIC FILINGS WITH THE UNITED STATES SECURITIES AND EXCHANGE COMMISSION (SEC), INCLUDING THE “RISK FACTORS” SECTIONS OF ZS PHARMA’S ANNUAL REPORT ON FORM 10-K FOR THE YEAR ENDED DECEMBER 31, 2014 AND SUBSEQUENT QUARTERLY REPORTS ON FORM 10-Q, AS WELL AS THE TENDER OFFER DOCUMENTS TO BE FILED BY SUBSIDIARIES OF ASTRAZENECA AND THE SOLICITATION/RECOMMENDATION TO BE FILED BY ZS PHARMA. THESE STATEMENTS ARE BASED ON CURRENT EXPECTATIONS, ASSUMPTIONS, ESTIMATES AND PROJECTIONS, AND INVOLVE KNOWN AND UNKNOWN RISKS, UNCERTAINTIES AND OTHER FACTORS THAT MAY CAUSE RESULTS, LEVELS OF ACTIVITY, PERFORMANCE OR ACHIEVEMENTS TO BE MATERIALLY DIFFERENT FROM ANY FUTURE STATEMENTS. THESE STATEMENTS ARE GENERALLY IDENTIFIED BY WORDS OR PHRASES SUCH AS “BELIEVE,” “ANTICIPATE,” “EXPECT,” “INTEND,” “PLAN,” “WILL,” “MAY,” “SHOULD,” “ESTIMATE,” “PREDICT,” “POTENTIAL,” “CONTINUE” OR THE NEGATIVE OF SUCH TERMS OR OTHER SIMILAR EXPRESSIONS. IF UNDERLYING ASSUMPTIONS PROVE INACCURATE OR UNKNOWN RISKS OR UNCERTAINTIES MATERIALIZE, ACTUAL RESULTS AND THE TIMING OF EVENTS MAY DIFFER MATERIALLY FROM THE RESULTS AND/OR TIMING DISCUSSED IN THE FORWARD-LOOKING STATEMENTS, AND YOU SHOULD NOT PLACE UNDUE RELIANCE ON THESE STATEMENTS. ASTRAZENECA AND ZS PHARMA DISCLAIM ANY INTENT OR OBLIGATION TO UPDATE ANY FORWARD-LOOKING STATEMENTS AS A RESULT OF DEVELOPMENTS OCCURRING AFTER THE DATE HEREOF OR OTHERWISE.

ADDITIONAL INFORMATION AND WHERE TO FIND IT

THIS COMMUNICATION IS FOR INFORMATIONAL PURPOSES ONLY AND DOES NOT CONSTITUTE AN OFFER TO PURCHASE OR A SOLICITATION OF AN OFFER TO SELL ZS PHARMA COMMON STOCK. THE OFFER TO BUY ZS PHARMA COMMON STOCK WILL ONLY BE MADE PURSUANT TO A TENDER OFFER STATEMENT (INCLUDING THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND OTHER RELATED TENDER OFFER MATERIALS). INVESTORS AND SECURITY HOLDERS ARE URGED TO READ BOTH THE TENDER OFFER STATEMENT (WHICH WILL BE FILED BY SUBSIDIARIES OF ASTRAZENECA WITH THE SEC AND THE SOLICITATION/RECOMMENDATION STATEMENT ON SCHEDULE 14D-9 WITH RESPECT TO THE TENDER OFFER (WHICH WILL BE FILED BY ZS PHARMA WITH THE SEC) WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION, INCLUDING THE TERMS AND CONDITIONS OF THE OFFER. INVESTORS AND SECURITY HOLDERS MAY OBTAIN A FREE COPY OF THESE MATERIALS (WHEN AVAILABLE) AND OTHER DOCUMENTS FILED BY ASTRAZENECA AND ZS PHARMA WITH THE SEC AT THE WEBSITE MAINTAINED BY THE SEC AT WWW.SEC.GOV. THE TENDER OFFER STATEMENT AND RELATED MATERIALS, AND THE SOLICITATION/RECOMMENDATION STATEMENT, MAY ALSO BE OBTAINED (WHEN AVAILABLE) FOR FREE BY CONTACTING ASTRAZENECA INVESTOR RELATIONS – SEE CONTACT DETAILS BELOW.

COPIES OF THESE MATERIALS AND ANY DOCUMENTATION RELATING TO THE TENDER OFFER ARE NOT BEING, AND MUST NOT BE, DIRECTLY OR INDIRECTLY, MAILED OR OTHERWISE FORWARDED, DISTRIBUTED OR SENT IN, INTO OR FROM ANY JURISDICTION WHERE TO DO SO WOULD BE UNLAWFUL.

Page 3/5

News Release

NOTES TO EDITORS

About Hyperkalaemia

Hyperkalaemia, or high potassium levels, occurs in 23-47% of patients with chronic kidney disease and/or chronic heart failure, and can lead to cardiac arrest and death (mortality up to 20%). Treatment with common heart medicines can also be responsible for increases in hyperkalaemia. Current therapeutic options are limited, leaving high unmet medical need, in particular for treatments with rapid onset of action and no significant drug-drug interaction risk.

About ZS-9

ZS-9 is a proprietary zirconium silicate compound and is manufactured as odourless, tasteless crystals. It acts as a highly selective potassium trap, is administered orally in 5 to 15g doses mixed with three tablespoons of water, is not systemically absorbed and is excreted in faeces. Clinical studies indicate that ZS-9 is stable at room temperature and has a rapid onset of action. Current estimates for global peak year sales of ZS-9 exceed $1 billion. Pending and granted patents, some under license, have expiries out to 2032 and beyond.

About ZS Pharma

ZS Pharma, founded in 2008, is a publicly traded biopharmaceutical company dedicated to challenging the status quo in disease states where therapeutic options have been limited. The company has been focused on using its proprietary ion-trap technology to develop new treatments of kidney and liver diseases that are focused on addressing unmet needs in the medical community. For more information, please visit: www.zspharma.com.

About AstraZeneca in Cardiovascular & Metabolic Disease (CVMD)

Cardiovascular, metabolic disease and chronic kidney disease are key areas of focus for AstraZeneca as part of the company’s strategy for achieving scientific leadership and returning to growth. Our patient-led strategy is focused on addressing the multiple risk factors facing CVMD and CKD patients at different stages of their disease, with the goal of reducing morbidity and mortality through life changing medicines. One of the innovative medicines currently in Phase III development is roxadustat as a potential therapy for anaemia associated with chronic kidney disease, in patients on dialysis and those who are not on dialysis. The global development programme is being conducted by FibroGen in collaboration with AstraZeneca and Astellas.

About AstraZeneca

AstraZeneca is a global, innovation-driven biopharmaceutical business that focuses on the discovery, development and commercialisation of prescription medicines, primarily for the treatment of cardiovascular, metabolic, respiratory, inflammation, autoimmune, oncology, infection and neuroscience diseases. 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.

CONTACTS

Media Enquiries
Esra Erkal-Paler	UK/Global	+44 20 7604 8030

Page 4/5

News Release

Vanessa Rhodes		UK/Global	+44 20 7604 8037
Ayesha Bharmal		UK/Global	+44 20 7604 8034
Karen Birmingham		UK/Global	+44 20 7604 8120
Jacob Lund		Sweden	+46 8 553 260 20
Michele Meixell		US	+1 302 885 2677
Investor Enquiries
UK
Thomas Kudsk Larsen	Oncology	+44 20 7604 8199	+44 7818 524185
Eugenia Litz	RIA	+44 20 7604 8233	+44 7884 735627
Nick Stone	CVMD	+44 1763 263 994	+44 7717 618834
Craig Marks	Finance	+44 20 7604 8591	+44 7881 615764
Christer Gruvris	Consensus Forecasts	+44 20 7604 8126	+44 7827 836825
US
Lindsey Trickett	Oncology, ING	+1 301 398 5118	+1 240 543 7970
Mitch Chan	Oncology	+1 301 398 1849	+1 240 477 3771
Dial / Toll-Free		+1 301 398 3251	+1 866 381 7277

Key: RIA - Respiratory, Inflammation and Autoimmunity, CVMD - Cardiovascular and Metabolic Disease,

ING - Infection, Neuroscience and Gastrointestinal

Page 5/5

EX-99.2

Exhibit 99.2

Subject: Message from Pascal Soriot, CEO AstraZeneca

Dear all,

Following today’s announcement, I wanted to share why I am so excited by the agreement that I hope will see ZS Pharma soon join AstraZeneca.

Cardiovascular and metabolic disease is one of AstraZeneca’s main therapy areas and ZS Pharma will have an extremely important role to play in working with us to achieve our core purpose: to push the boundaries of science to deliver life-changing medicines.

As you know, cardiovascular and metabolic disease affects hundreds of millions of people around the world and there is high unmet medical need. AstraZeneca has been driving innovation in this space for more than 100 years and we are committed to reducing morbidity, mortality and organ damage by addressing multiple risk factors across cardiovascular disease, diabetes and chronic kidney disease. You are making a great contribution to developing an innovative treatment to address one of them – hyperkalaemia, a leading cause of mortality in patients suffering from chronic kidney disease and chronic heart failure. The alignment with our work at AstraZeneca is clear.

At AstraZeneca we share your entrepreneurial mindset, commitment to science and passion to make a difference. By combining the expertise, know-how and capabilities of ZS Pharma with AstraZeneca’s existing teams and portfolio of innovative medicines, we will together be in a stronger position to make an even bigger difference in the lives of many people around the world.

What’s more, you will be joining AstraZeneca at a tremendously exciting time – we have built one of the most promising pipelines in the industry and we are rapidly accelerating its delivery. I had the pleasure of announcing our third quarter and nine months results only yesterday and we once again reported strong scientific and commercial progress. With ZS Pharma joining the team our progress will accelerate further still.

I recognize that joining a global company of more than 57,000 employees may bring uncertainty and excitement in equal measure. With this in mind, we have already formed a team to plan and support you during this transition. This team will solely focus on ensuring that you feel part of AstraZeneca as quickly as possible after completion, with the independence to pursue the full potential of ZS-9. This is consistent with the approach we have taken with Ardea Biosciences in San Diego and Pearl Therapeutics in Redwood City previously. AstraZeneca is a great place to work and I know you will help us to make it even better.

Please don’t let today’s news distract you. With patients waiting, the progress you are making every single day to address the unmet medical need for innovative hyperkalaemia treatments remains as valuable and urgent as ever.

I look forward to welcoming you to AstraZeneca and to working alongside you soon.

Pascal

Pascal Soriot

Chief Executive Officer

AstraZeneca

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

SOME OF THE STATEMENTS CONTAINED IN THIS ANNOUNCEMENT ARE FORWARD-LOOKING STATEMENTS, INCLUDING STATEMENTS REGARDING THE EXPECTED CONSUMMATION OF THE ACQUISITION, WHICH INVOLVES A NUMBER OF RISKS AND UNCERTAINTIES, INCLUDING THE SATISFACTION OF CLOSING CONDITIONS FOR THE ACQUISITION, SUCH AS REGULATORY APPROVAL FOR THE TRANSACTION, THE TENDER OF A MAJORITY OF THE OUTSTANDING SHARES OF COMMON STOCK OF ZS PHARMA, THE POSSIBILITY THAT THE TRANSACTION WILL NOT BE COMPLETED AND OTHER RISKS AND UNCERTAINTIES DISCUSSED IN ZS PHARMA’S PUBLIC FILINGS WITH THE UNITED STATES SECURITIES AND EXCHANGE COMMISSION (SEC), INCLUDING THE “RISK FACTORS” SECTIONS OF ZS PHARMA’S ANNUAL REPORT ON FORM 10-K FOR THE YEAR ENDED DECEMBER 31, 2014 AND SUBSEQUENT QUARTERLY REPORTS ON FORM 10-Q, AS WELL AS THE TENDER OFFER DOCUMENTS TO BE FILED BY SUBSIDIARIES OF ASTRAZENECA AND THE SOLICITATION/RECOMMENDATION TO BE FILED BY ZS PHARMA. THESE STATEMENTS ARE BASED ON CURRENT EXPECTATIONS, ASSUMPTIONS, ESTIMATES AND PROJECTIONS, AND INVOLVE KNOWN AND UNKNOWN RISKS, UNCERTAINTIES AND OTHER FACTORS THAT MAY CAUSE RESULTS, LEVELS OF ACTIVITY, PERFORMANCE OR ACHIEVEMENTS TO BE MATERIALLY DIFFERENT FROM ANY FUTURE STATEMENTS. THESE STATEMENTS ARE GENERALLY IDENTIFIED BY WORDS OR PHRASES SUCH AS “BELIEVE,” “ANTICIPATE,” “EXPECT,” “INTEND,” “PLAN,” “WILL,” “MAY,” “SHOULD,” “ESTIMATE,” “PREDICT,” “POTENTIAL,”

“CONTINUE” OR THE NEGATIVE OF SUCH TERMS OR OTHER SIMILAR EXPRESSIONS. IF UNDERLYING ASSUMPTIONS PROVE INACCURATE OR UNKNOWN RISKS OR UNCERTAINTIES MATERIALIZE, ACTUAL RESULTS AND THE TIMING OF EVENTS MAY DIFFER MATERIALLY FROM THE RESULTS AND/OR TIMING DISCUSSED IN THE FORWARD-LOOKING STATEMENTS, AND YOU SHOULD NOT PLACE UNDUE RELIANCE ON THESE STATEMENTS.

ASTRAZENECA AND ZS PHARMA DISCLAIM ANY INTENT OR OBLIGATION TO UPDATE ANY FORWARD-LOOKING STATEMENTS AS A RESULT OF DEVELOPMENTS OCCURRING AFTER THE DATE HEREOF OR OTHERWISE.

ADDITIONAL INFORMATION AND WHERE TO FIND IT 

THIS COMMUNICATION IS FOR INFORMATIONAL PURPOSES ONLY AND DOES NOT CONSTITUTE AN OFFER TO PURCHASE OR A SOLICITATION OF AN OFFER TO SELL ZS PHARMA COMMON STOCK. THE OFFER TO BUY ZS PHARMA COMMON STOCK WILL ONLY BE MADE PURSUANT TO A TENDER OFFER STATEMENT (INCLUDING THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND OTHER RELATED TENDER OFFER MATERIALS). INVESTORS AND SECURITY HOLDERS ARE URGED TO READ BOTH THE TENDER OFFER STATEMENT (WHICH WILL BE FILED BY SUBSIDIARIES OF ASTRAZENECA WITH THE SEC AND THE SOLICITATION/RECOMMENDATION STATEMENT ON SCHEDULE 14D-9 WITH RESPECT TO THE TENDER OFFER (WHICH WILL BE FILED BY ZS PHARMA WITH THE SEC) WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION, INCLUDING THE TERMS AND CONDITIONS OF THE OFFER. INVESTORS AND SECURITY HOLDERS MAY OBTAIN A FREE COPY OF THESE MATERIALS (WHEN AVAILABLE) AND OTHER DOCUMENTS FILED BY ASTRAZENECA AND ZS PHARMA WITH THE SEC AT THE WEBSITE MAINTAINED BY THE SEC AT WWW.SEC.GOV. THE TENDER OFFER STATEMENT AND RELATED MATERIALS, AND THE SOLICITATION/RECOMMENDATION STATEMENT, MAY ALSO BE OBTAINED (WHEN AVAILABLE) FOR FREE BY CONTACTING ASTRAZENECA INVESTOR RELATIONS AT IRTEAM@ASTRAZENECA.COM/+442076048127.

COPIES OF THESE MATERIALS AND ANY DOCUMENTATION RELATING TO THE TENDER OFFER ARE NOT BEING, AND MUST NOT BE, DIRECTLY OR INDIRECTLY, MAILED OR OTHERWISE FORWARDED, DISTRIBUTED OR SENT IN, INTO OR FROM ANY JURISDICTION WHERE TO DO SO WOULD BE UNLAWFUL.

EX-99.3

Exhibit 99.3

A cquisition of ZS Pharma Conference call 6 November 2015

This document contains certain forward - looking statements with respect to the operations, performance and financial condition of the Group, including, among other things, statements about expected revenues, margins, earnings per share or other financial or other measures . Although we believe our expectations are based on reasonable assumptions, any forward - looking statements, by their very nature, involve risks and uncertainties and may be influenced by factors that could cause actual outcomes and results to be materially different from those predicted . The forward - looking statements reflect knowledge and information available at the date of preparation of this document and AstraZeneca undertakes no obligation to update these forward - looking statements . We identify the forward - looking statements by using the words 'anticipates', 'believes', 'expects', 'intends' and similar expressions in such statements . Important factors that could cause actual results to differ materially from those contained in forward - looking statements, certain of which are beyond our control, include, among other things : the loss or expiration of, or limitations to, patents , marketing exclusivity or trademarks, or the risk of failure to obtain and enforce patent protection ; the risk of substantial adverse litigation/government investigation claims and insufficient insurance coverage ; effects of patent litigation in respect of IP rights ; exchange rate fluctuations ; the risk that R&D will not yield new products that achieve commercial success ; the risk that strategic alliances and acquisitions, including licensing and collaborations, will be unsuccessful ; the impact of competition, price controls and price reductions ; taxation risks ; the risk of substantial product liability claims ; the impact of any delays in the manufacturing, distribution and sale of any of our products ; the impact of any failure by third parties to supply materials or services ; the risk of failure of outsourcing ; the risks associated with manufacturing biologics ; the risk of delay to new product launches ; the difficulties of obtaining and maintaining regulatory approvals for products ; the risk of failure to adhere to applicable laws, rules and regulations ; the risk of failure to adhere to applicable laws, rules and regulations relating to anti - competitive behaviour ; the risk that new products do not perform as we expect ; failure to achieve strategic priorities or to meet targets or expectations ; the risk of an adverse impact of a sustained economic downturn ; political and socio - economic conditions ; the risk of environmental liabilities ; the risk of occupational health and safety liabilities ; the risk associated with pensions liabilities ; the risk of misuse of social medial platforms and new technology ; the risks associated with developing our business in emerging markets ; the risk of illegal trade in our products ; the risks from pressures resulting from generic competition ; the risk of failure to successfully implement planned cost reduction measures through productivity initiatives and restructuring programmes ; economic, regulatory and political pressures to limit or reduce the cost of our products ; the risk that regulatory approval processes for biosimilars could have an adverse effect on future commercial prospects ; the impact of failing to attract and retain key personnel and to successfully engage with our employees ; the impact of increasing implementation and enforcement of more stringent anti - bribery and anti - corruption legislation ; and the risk of failure of information technology and cybercrime . Nothing in this presentation / webcast should be construed as a profit forecast . 2 Forward - looking statements

Some of the statements contained in this announcement are forward - looking statements, including statements regarding the expected consummation of the acquisition, which involves a number of risks and uncertainties, including the satisfaction of closing conditions for the acquisition, such as regulatory approval for the transaction, the tender of a majority of the outstanding shares of common stock of ZS Pharma, the possibility that the transaction will not be completed and other risks and uncertainties discussed in ZS Pharma’s public filings with the United States Securities and Exchange Commission (SEC), including the “Risk Factors” sections of ZS Pharma’s Annual Report on Form 10 - K for the year ended December 31 , 2014 and subsequent quarterly reports on Form 10 - Q, as well as the tender offer documents to be filed by subsidiaries of AstraZeneca and the solicitation/recommendation to be filed by ZS Pharma . These statements are based on current expectations, assumptions, estimates and projections, and involve known and unknown risks, uncertainties and other factors that may cause results, levels of activity, performance or achievements to be materially different from any future statements . These statements are generally identified by words of phrases such as “believe”, “anticipate”, “expect”, “intend”, “plan”, “will”, “may”, “should”, “estimate”, “predict”, “potential”, “continue” or the negative of such terms or other similar expressions . If underlying assumptions prove inaccurate or unknown risks or uncertainties materialise, actual results and the timing of events may differ materially from the results and/or timing discussed in the forward - looking statements, and you should not place undue reliance on these statements . AstraZeneca and ZS Pharma disclaim any intent or obligation to update any forward - looking statements as a result of developments occurring after the date hereof or otherwise . Additional information and where to find it These materials are for informational purposes only and does not constitute an offer to purchase or a solicitation of an offer to sell ZS Pharma common stock . The offer to buy ZS Pharma common stock will only be made pursuant to a tender offer statement (including the offer to purchase, letter of transmittal and other related tender offer materials) . Investors and security holders are urged to read both the tender offer statement (which will be filed by subsidiaries of AstraZeneca with the Securities and Exchange Commission (SEC)) and the solicitation/recommendation statement on schedule 14 D - 9 with respect to the tender offer (which will be filed by ZS Pharma with the SEC) when they become available because they will contain important information, including the terms and conditions of the offer . Investors and security holders may obtain a free copy of these materials (when available) and other documents filed by AstraZeneca and ZS Pharma with the SEC at the website maintained by the SEC at www . sec . gov . T he tender offer statement and related materials, and the solicitation/recommendation statement, may also be obtained (when available) for free by contacting AstraZeneca Investor Relations at irteam@astrazeneca . com . Copies of these materials and any documents relating to the tender offer are not being, and must not be, directly or indirectly, mailed or otherwise forwarded, distributed or sent in, into or from any jurisdiction where to do so would be unlawful . 3 Forward - looking statements continued

4 Agenda Overview Pascal Soriot Opportunity Luke Miels Clinical Sean Bohen Terms Marc Dunoyer Summary Pascal Soriot

Strengthens focus in Cardiovascular & Metabolic Disease • Adds ZS - 9, potential best - in - class specialty treatment • Leverages roxadustat and Diabetes franchise Hyperkalaemia can be a life - threatening condition • C hronic kidney disease (CKD) and chronic heart failure (CHF) with increasing prevalence • Limited alternative treatment options, current and near term > 3 million patients with hyperkaleamia in the US Global potential peak - year sales >$ 1bn Transaction supports Return to Growth strategy • Anticipated Product Sales from 2016; PDUFA date: 26 May 2016 • E xpected growth in all regions, including Emerging Markets Core EPS - accretive from 2018; marginally dilutive in 2016 & 2017 5 Overview

6 Cardiovascular & Metabolic Disease strategy Cardiovascular Metabolism CKD • ZS - 9 cardio - renal opportunity with potential launch in 2016 • Leverages roxadustat and Diabetes franchise Reducing cardiovascular morbidity, mortality and organ damage by addressing multiple risk factors

• Publicly traded (NASDAQ: ZSPH) • Founded in 2008; h eadquartered in San Mateo, California • Development manufacturing site in Coppell, Texas • ~ 200 employees • Strong expertise, know - how and capabilities in CKD • Net cash position 7 About ZS Pharma

8 Hyperkalaemia is a leading cause of mortality in CKD 1.00 1.07 1.04 1.27 10.32 5.35 5.73 2.31 31.64 19.52 11.56 8.02 None Stage 3 Stage 4 Stage 5 Severity of CKD <5.5 ≥5.5 & ≤6.0 >6.0 Odds ratio of death within 24hr period after hyperkalaemia Source: Arch Intern Med. 22 June 2009; 169(12): 1156 - 1162.doi:10.1001/archinternmed.2009.132. K+ level, mEq/L

9 CKD prevalence in key markets 6.6m 6.0 m 12.7 m 701k 645k 3.9m 5.5 m 18.1m 943k 365k 2.1m 4.9m 6.3m 515k 343 k US: 27m EU5: 29m JPN: 14m Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 Source: Decision Resources Group, Chronic Kidney Disease Patient Base, May 2015

“The medications linked to hyperkalaemia that are most relevant are RAAS inhibitors (ACE inhibitors, ARBs, direct renin inhibitors and mineralocorticoid - receptor blockers).” “Maintaining the use of these beneficial medications while implementing various strategies to control potassium balance is desirable; however, discontinuation rates remain high.” 10 Source: Kovesdy, C.P. Nat. Rev. Nephrol . 10, 653 - 662 (2014); published online 16 September 2014; doi:10.1038/nrneph.2014.168

Source: Einhorn LM, Zhan M, Hsu VD, et al. The frequency of hyperkalemia and its significance in CKD. Arch Intern Med. 2009;169(12):1 156 - 1162. doi:10.1001/archinternmed.2009.132. 11 Causes of hyperkalaemia in CKD/CHF Those with chronic disease … Affected by HK 1 20 – 50% CKD Up to 20% CHF … and on lifesaving RAASi therapies High K+ cited by nephrologists and cardiologists as key reason for under utilising RAASi therapy in CHF and CKD ACEs, ARBs and a ldosterone antagonists K +

K+ level (mEq/L) Mild Moderate Severe Treatment Titrate RAASi, adjust diet Titrate RAASi, adjust diet, +/ - kayexalate Discontinue RAASi, +/ - emergency measures 12 Limited alternative treatment options Current treatment o ptions Phase I, II, III: 0 Submitted: ZS - 9 Approved: patiromer Marketed : kayexalate 5.0 5.5 6.0 Source: Company data, Morgan Stanley research

13 ZS - 9: Potential best - in - class treatment for hyperkalaemia • Proprietary zirconium silicate compound • Non - systemically absorbed • Odourless , tasteless 5 - 15g once a day • Onset of action ~2hrs • No significant drug - drug interaction • Long - term stability at room temperature • Pending and granted patents with expiries out to 2032 and beyond Crystal structure Ion selectivity for K+ only K + Zr Zr Zr Si Si Si Si O O O O O O O

14 ZS - 9: ~1,700 patients in clinical development programme Trial Published Trial type # Patients Duration Endpoint ZS002 (Completed) Phase II Double - blind RCT N=90 Serum K 5.0 – 6.0 mEq/L 48 hours ∆ serum K+ level (3 doses) ZS003 (Completed) Phase III Double - blind RCT N=753 Serum K 5.0 – 6.5 mEq/L 14 days ∆ serum K+ level (4 doses) ZS004e (Completed/ extension o ngoing) Phase III Double - blind RCT N=258 Serum K >5.0 mEq/L 1 month + 11 month extension Maintenance of serum K+ (28 days) ZS005 (Ongoing) Open - label safety trial N=750 Serum K >5.0 mEq/L 12 months Safety & tolerability of long - term dose (i nitiated Q2 2014)

15 ZS - 9: Efficacy summary • All trials met primary endpoints • Trials in CKD , CHF , d iabetic patients • Reduction in aldosterone • Increase in bicarbonate levels 50% 84% 98% By 2.2hrs By 24hrs By 48hrs Onset of action (day 1 - 2) Percent of patients K + normalised Onset of action (day 1 - 2) K + decreases in severe patients (>6.0mEq/L ) 0.7 mEq/L 0.6 mEq/L 0.4 mEq/L 1hrs 2hrs 4hrs Source: Aggregated clinical trial data from company due diligence. Data on file.

16 ZS - 9: Safety and tolerability summary • Gastrointestinal adverse - event rates comparable to placebo (<1 %) • No clinically - significant changes in sodium, magnesium or calcium levels • Few hypokalaemia cases below 3.0mEq/L • Peripheral oedema 1.0% (<2.5g), 0.0% (5g), 4.4% (10g), 10.7% (15g) and 1.7% (placebo) 1 Source: 1. Company due diligence. treatment - emergent adverse events reported by >2.0% of subjects in any treatment group (safety populat ion; completed trial ZS - 003 and ZS - 004 )

• Upon completion ZS Pharma will become a wholly - owned subsidary • All - cash transaction to acquire all of the outstanding capital stock of ZS Pharma for $90 per share; approximately $2.7 billion in aggregate transaction value • M erger in which each remaining untendered share of ZS Pharma common stock would be converted into the same $90 per share cash consideration as in the tender offer • Subject to the tender of a majority of the outstanding shares of ZS Pharma common s tock and other and customary conditions • Transaction expected to close this year • Financed with a combination of cash and debt • Acquisition accounted for as business combination 17 Transaction terms

• Strengthens focus in Cardiovascular & Metabolic Disease • Hyperkalaemia can be a life - threatening condition • >3 million patients with hyperkaleamia in the US • Global potential peak - year sales >$ 1bn • Transaction supports Return to Growth strategy • Core EPS - accretive from 2018; marginally dilutive in 2016 & 2017 18 Summary

19 Questions

EX-99.4

Exhibit 99.4

Q&A

Project Zanzibar 

FINAL: 6 November 2015

PROJECT ZANZIBAR  

KEY MESSAGES AND Q&A

6 November 2015

Key messages

• AstraZeneca has entered into an agreement to acquire ZS Pharma for $90 per share.

• This acquisition strengthens our focus in Cardiovascular & Metabolic Disease by adding to our portfolio ZS-9, a potential best-in-class treatment for hyperkalaemia. It also leverages roxadustat and our diabetes franchise.

• Hyperkalaemia affects more than 3 million patients suffering from chronic kidney disease (CKD) and chronic heart failure (CHF) in the U.S. alone. It can be a life-threatening condition with limited alternative treatment options.

• ZS-9 is currently under FDA regulatory review with a PDUFA date of 26 May 2016 and planned EU regulatory submission in Q4 2015.

• The transaction supports our Return to Growth strategy with ZS-9 global potential peak-year sales estimated to be above $1bn.

Q&A

Strategic rationale

1. What is the strategic rationale for the acquisition?

The acquisition provides a strong strategic fit with AstraZeneca’s pipeline and portfolio in cardiovascular and metabolic diseases, including the company’s investigational medicine for patients with anaemia associated with chronic kidney disease, roxadustat, which is currently in Phase III development.

It gives AstraZeneca access to the potassium-binding compound ZS-9, a potential best-in-class treatment for hyperkalaemia that is currently under regulatory review in the US, with a PDUFA date of 26 May 2016. ZS-9 therefore has potential to provide product sales from 2016, benefitting AstraZeneca’s return to growth.

2. How does ZS-9 fit alongside your existing portfolio, in particular roxadustat?

Both anaemia and hyperkalaemia are serious complications of chronic kidney disease. Most patients with chronic hyperkalaemia also have coexisting conditions including chronic kidney disease, heart failure, hypertension and diabetes - conditions addressed through our current portfolio in cardiovascular and metabolic diseases, as well as the investigational medicines within our late stage pipeline.

ZS-9 has the potential to be a best-in-class new treatment option for patients and their physicians. We expect that the capabilities and commercial expertise we build together with our new members joining us from ZS to launch ZS-9 will benefit the future launch of roxadustat.

3. Does the acquisition accelerate the infrastructure needed to support roxadustat? How are you preparing for the launch of roxadustat? Does this acquisition give you a competitive advantage?

Q&A 

Project Zanzibar

FINAL: 6 November 2015

We expect that the capabilities and commercial expertise we build together with our new members joining us from ZS to launch ZS-9 will also benefit the future launch of roxadustat. There is significant overlap between healthcare professionals managing patients at risk of hyperkalaemia, and the expected prescribers of roxadustat.

4. Previously you committed to investors that you were not interested in pipeline deals; why did you choose to execute this transaction given it destroys EPS value in the near-term?

This deal will contribute benefit AstraZeneca’s return to growth and be accretive from 2018 (with minimal dilution in 2016 & 2017). The acquisition is fully in line with our strategy of investing to add potential best-in-class products to our pipeline in our main therapeutic areas. The acquisition of ZS Pharma gives us access to a near launch-ready, potential best-in-class asset in ZS-9, which, if approved in the US in H1 2016, will start bringing in revenue to contribute to our top line by early in the second half of next year.

This deal represents a rare opportunity to acquire a potential best-in-class asset that is already in the final stages of regulatory review in a key market. In addition, the near-term dilution will be fully recovered in the mid- to long-term through value produced by building the capabilities and commercial expertise for ZS-9 that will also be leveraged when we launch roxadustat.

5. When do you anticipate approval/launch of roxadustat?

We anticipate filing roxadustat in major markets (US, EU, Japan) in 2H 2016.

6. Does ZS Pharma have any other assets of interest to AZN beyond ZS-9?

In addition to ZS-9, ZS Pharma has a number of promising preclinical programmes that leverage the company’s zirconium cyclosilicate technology.

Deal structure and financials

7. What is the transaction structure? Did you consider contingent value rights (CVR) to mitigate the risk?

Under the terms of the agreement, AstraZeneca will acquire all of the outstanding capital stock of ZS Pharma for $90 per share.

AstraZeneca reviewed a number of potential deal structures and vehicles. We believe the proposed deal structure is in the best interests of both parties.

8. Does this deal represent good value for money? What assessment of ZS-9 peak year sales – if approved - is it based on?

Based on our assessment of the high unmet need associated with the treatment of hyperkalaemia, the limitations of current therapeutic options and the potential best-in-class profile of ZS-9 we expect the acquisition to represent good value and provide an opportunity to accelerate our entry into the chronic kidney disease market, a strategically important area for AstraZeneca.

The current estimate of peak year sales for ZS-9 is over a billion dollars globally.

9. How do you intend to finance the acquisition?

We will use a combination of cash resources on hand and debt.

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Q&A 

Project Zanzibar

FINAL: 6 November 2015

10. What will be the impact on your credit rating?

We are in discussion with the agencies whom we expect to confirm the impact on our credit rating in the very near term. As a best-in-class specialty treatment that supports or Return to Growth strategy in the near term, we do not anticipate a significant impact on our ratings.

11. What does minimal dilution mean for your Core EPS in 2016 and 2017? Will you still be able to hit $4.20?

We anticipate minimal dilution to our core earnings in 2016 and 2017 from this transaction.  Consistent with our long-term practice we will provide guidance on our 2016 Core EPS alongside our full year results on 4^th February 2016.

12. Was this a competitive process? Did you have to overpay as a result? Do you expect a counter bid from Actelion or others?

Yes, it was a competitive process. Based on our assessment of the high unmet need associated with the treatment of hyperkalaemia, the limitations of current therapeutic options and the potential best-in-class profile of ZS-9 we expect the acquisition to represent good value and provide an opportunity to accelerate our entry into the chronic kidney disease market, a strategically important area for AstraZeneca. The current estimate of peak year sales for ZS-9 is over a billion dollars globally.

We cannot speculate on the actions of any other company.

13. How will you account for this transaction?

The transaction will be accounted for as a business combination, therefore, all assets and liabilities acquired (including intangible assets and goodwill) will be recorded at fair value at closing.

ZS-9

14. How does ZS-9 compare against kayexalate and patiromer (Veltassa)? What are the advantages?

ZS-9 is a proprietary sodium zirconium cyclosilicate compound and is fundamentally different from other hyperkalaemia treatments currently on the market, kayexalate and patiromer (Veltassa), which are both organic polymers.

ZS-9 is a proprietary zirconium silicate compound and is manufactured as odourless, tasteless crystals. It acts as a highly selective potassium trap, is administered orally in 5 to 15g doses mixed with three tablespoons of water, is not systemically absorbed and is excreted in faeces.

15. Are there any risks this asset could receive a ‘Black Box’ warning like Relypsa’s Veltassa, or is this a potential differentiator for ZS-9?

ZS-9 and patiromer (Veltassa) are very different compounds from both a structural and mechanism of action perspective. ZS-9 is very selective for potassium and is not absorbed systemically.

16. Is the product really differentiated? Its attributes seem limited to convenience.

ZS-9 is a proprietary zirconium silicate compound and is manufactured as odourless, tasteless crystals. It acts as a highly selective potassium trap, is administered orally in 5 to 15g doses mixed with three tablespoons of water, is not systemically absorbed and is excreted in faeces.

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Q&A 

Project Zanzibar

FINAL: 6 November 2015

17. How confident are you that you will achieve regulatory approval? Based on your recent experience with saxa/dapa are you confident that the regulatory submission is sufficient to gain approval?

While we cannot pre-empt any regulatory decision from the FDA, we believe the current filing will support regulatory approval.

18. Assuming approval, when do you anticipate launch in the US?

Assuming ZS-9 receives approval from the US FDA on 26 May 2016, in line with the current PDUFA date, we would anticipate launching the product shortly after this.

19. Does the asset have potential beyond the initial indication i.e. in LCM?

We will continue to explore additional studies and indications for ZS-9 but at present, our focus is on the hyperkalaemia indication currently filed in the US.

20. What phase II and/or abstract data is in the public domain? Have you had sight of the abstracts from the long-term safety study of ZS-9, due to be presented as a poster at the American Society of Nephrology's Kidney Week on 7 November?

Several publications relating to data on ZS-9 are available and in the public domain:

· HS, Lavin PT, et al. Sodium zirconium cyclosilicate in hyperkalaemia. N Engl J Med. 2015;372(3):222-231. doi:10.1056/NEJMoa1411487.

· Kosiborod M, Rasmussen HS, Lavin P, et al. Effect of sodium zirconium cyclosilicate on potassium lowering for 28 days among outpatients with hyperkalaemia: the HARMONIZE randomized clinical trial. JAMA. 2014; 312(21):2223-2233. doi:10.1001/jama.2014.15688.

· Packham DK, et al. Phase 2 study on the treatment of hyperkalaemia in patients with chronic kidney disease suggests that the selective potassium trap, ZS-9, is safe and efficient. Kidney International (2015) 88, 404–411.

At ASN ZS pharma will be presenting data from the first 700 patients enrolled into its long term open label 12 month safety and efficacy study.

21. What is the commercial opportunity for ZS-9? What is the geographic distribution of the addressable patient population?

Chronic hyperkalaemia is a fairly common and potentially life-threatening condition, affecting over 3 million patients in the US alone. A significant unmet medical need remains for these patients with very limited effective treatment options currently available. Most patients with hyperkalaemia also have other conditions including CKD, heart failure, diabetes and hypertension and are typically receiving numerous other medications, some of which also raise serum potassium levels (i.e. RAAS inhibitors, ACE inhibitors, ARBs etc.).  ZS-9 rapidly and selectively returns serum potassium to normokalemic levels.

ZS-9 is currently under regulatory review in the US and is planned for filing in the EU by the end of 2015. AstraZeneca plans to seek approvals in other geographic regions. It is our intention to develop ZS-9 into a global brand.

22. How will it be priced?

We cannot comment on pricing decisions at this stage.

23. Where will ZS-9 be manufactured? At existing ZS Pharma facilities or at AZ manufacturing sites?

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Q&A 

Project Zanzibar

FINAL: 6 November 2015

ZS-9 substance will continue to be manufactured at the existing ZS Pharma site in Coppell, Texas to support product launch in the US. In addition, AZ will develop and execute a long-term manufacturing plan to meet future market demand.

24. Please describe your IP/patent position?

Pending and granted patents, some under license, have expiries out to 2032 and beyond.

Personnel

25. Will the approx. 200 staff become AZN employees?

Upon closing, all ZS Pharma employees will become AstraZeneca employees.

26. Given the continued SG&A pressures, what will happen to the three facilities and approx. 200 employees? Does this not add to the ongoing SG&A burden?

We expect to retain the know-how, talent and expertise within ZS. It is too early to comment in more detail at this stage.

An additional benefit is to strengthen our capability in cardio-renal. While some SG&A costs will be incurred, a significant proportion of the costs has already been accounted for in the projected launch of roxadustat. The revenues from ZS-9 will also help ease the SG&A burden, especially in the mid- to long-term.

27. Is there overlap with existing skills within AZN’s workforce? Are ZS Pharma employees at risk of job cuts/redundancy?

Upon closing, all ZS Pharma employees will become AstraZeneca employees. It is too early to comment in more detail at this stage.

28. What will happen to Robert Alexander? Will he be staying with AZ / managing ZS-9 going forward?

We expect to retain the know-how, talent and expertise within ZS. It is too early to comment in more detail at this stage.

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

SOME OF THE STATEMENTS CONTAINED IN THIS ANNOUNCEMENT ARE FORWARD-LOOKING STATEMENTS, INCLUDING STATEMENTS REGARDING THE EXPECTED CONSUMMATION OF THE ACQUISITION, WHICH INVOLVES A NUMBER OF RISKS AND UNCERTAINTIES, INCLUDING THE SATISFACTION OF CLOSING CONDITIONS FOR THE ACQUISITION, SUCH AS REGULATORY APPROVAL FOR THE TRANSACTION, THE TENDER OF A MAJORITY OF THE OUTSTANDING SHARES OF COMMON STOCK OF ZS PHARMA, THE POSSIBILITY THAT THE TRANSACTION WILL NOT BE COMPLETED AND OTHER RISKS AND UNCERTAINTIES DISCUSSED IN ZS PHARMA’S PUBLIC FILINGS WITH THE UNITED STATES SECURITIES AND EXCHANGE COMMISSION (SEC), INCLUDING THE “RISK FACTORS” SECTIONS OF ZS PHARMA’S ANNUAL REPORT ON FORM 10-K FOR THE YEAR ENDED DECEMBER 31, 2014 AND SUBSEQUENT QUARTERLY REPORTS ON FORM 10-Q, AS WELL AS THE TENDER OFFER DOCUMENTS TO BE FILED BY SUBSIDIARIES OF ASTRAZENECA AND THE SOLICITATION/RECOMMENDATION TO BE FILED BY ZS PHARMA. THESE STATEMENTS ARE BASED ON CURRENT EXPECTATIONS, ASSUMPTIONS,

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Q&A 

Project Zanzibar

FINAL: 6 November 2015

ESTIMATES AND PROJECTIONS, AND INVOLVE KNOWN AND UNKNOWN RISKS, UNCERTAINTIES AND OTHER FACTORS THAT MAY CAUSE RESULTS, LEVELS OF ACTIVITY, PERFORMANCE OR ACHIEVEMENTS TO BE MATERIALLY DIFFERENT FROM ANY FUTURE STATEMENTS. THESE STATEMENTS ARE GENERALLY IDENTIFIED BY WORDS OR PHRASES SUCH AS “BELIEVE,” “ANTICIPATE,” “EXPECT,” “INTEND,” “PLAN,” “WILL,” “MAY,” “SHOULD,” “ESTIMATE,” “PREDICT,” “POTENTIAL,” “CONTINUE” OR THE NEGATIVE OF SUCH TERMS OR OTHER SIMILAR EXPRESSIONS. IF UNDERLYING ASSUMPTIONS PROVE INACCURATE OR UNKNOWN RISKS OR UNCERTAINTIES MATERIALIZE, ACTUAL RESULTS AND THE TIMING OF EVENTS MAY DIFFER MATERIALLY FROM THE RESULTS AND/OR TIMING DISCUSSED IN THE FORWARD-LOOKING STATEMENTS, AND YOU SHOULD NOT PLACE UNDUE RELIANCE ON THESE STATEMENTS. ASTRAZENECA AND ZS PHARMA DISCLAIM ANY INTENT OR OBLIGATION TO UPDATE ANY FORWARD-LOOKING STATEMENTS AS A RESULT OF DEVELOPMENTS OCCURRING AFTER THE DATE HEREOF OR OTHERWISE.

ADDITIONAL INFORMATION AND WHERE TO FIND IT

THIS COMMUNICATION IS FOR INFORMATIONAL PURPOSES ONLY AND DOES NOT CONSTITUTE AN OFFER TO PURCHASE OR A SOLICITATION OF AN OFFER TO SELL ZS PHARMA COMMON STOCK. THE OFFER TO BUY ZS PHARMA COMMON STOCK WILL ONLY BE MADE PURSUANT TO A TENDER OFFER STATEMENT (INCLUDING THE OFFER TO PURCHASE, LETTER OF TRANSMITTAL AND OTHER RELATED TENDER OFFER MATERIALS). INVESTORS AND SECURITY HOLDERS ARE URGED TO READ BOTH THE TENDER OFFER STATEMENT (WHICH WILL BE FILED BY SUBSIDIARIES OF ASTRAZENECA WITH THE SEC AND THE SOLICITATION/RECOMMENDATION STATEMENT ON SCHEDULE 14D-9 WITH RESPECT TO THE TENDER OFFER (WHICH WILL BE FILED BY ZS PHARMA WITH THE SEC) WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION, INCLUDING THE TERMS AND CONDITIONS OF THE OFFER. INVESTORS AND SECURITY HOLDERS MAY OBTAIN A FREE COPY OF THESE MATERIALS (WHEN AVAILABLE) AND OTHER DOCUMENTS FILED BY ASTRAZENECA AND ZS PHARMA WITH THE SEC AT THE WEBSITE MAINTAINED BY THE SEC AT WWW.SEC.GOV. THE TENDER OFFER STATEMENT AND RELATED MATERIALS, AND THE SOLICITATION/RECOMMENDATION STATEMENT, MAY ALSO BE OBTAINED (WHEN AVAILABLE) FOR FREE BY CONTACTING ASTRAZENECA INVESTOR RELATIONS AT IRTEAM@ASTRAZENECA.COM/+442076048127. COPIES OF THESE MATERIALS AND ANY DOCUMENTATION RELATING TO THE TENDER OFFER ARE NOT BEING, AND MUST NOT BE, DIRECTLY OR INDIRECTLY, MAILED OR OTHERWISE FORWARDED, DISTRIBUTED OR SENT IN, INTO OR FROM ANY JURISDICTION WHERE TO DO SO WOULD BE UNLAWFUL.

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