• Soliris^® (eculizumab) net product sales were $898.2 million, compared to $813.3 million in the second quarter of 2017, representing a 10 percent increase. Soliris^® volume increased 11 percent year-over-year.
• Strensiq^® (asfotase alfa) net product sales were $125.1 million, compared to $83.6 million in the second quarter of 2017, representing a 50 percent increase. Strensiq^® volume increased 55 percent year-over-year.
• Kanuma^® (sebelipase alfa) net product sales were $21.4 million, compared to $15.3 million in the second quarter of 2017, representing a 40 percent increase. Kanuma^® volume increased 51 percent year-over-year.
• GAAP cost of sales was $95.3 million, compared to $83.6 million in the same quarter last year. Non-GAAP cost of sales was $89.3 million, compared to $78.0 million in the same quarter last year.
• GAAP R&D expense was $173.4 million compared to $198.2 million in the same quarter last year. Non-GAAP R&D expense was $158.3 million, compared to $177.6 million in the same quarter last year.
• GAAP SG&A expense was $277.3 million, compared to $265.6 million in the same quarter last year. Non-GAAP SG&A expense was $230.4 million, compared to $227.5 million in the same quarter last year.
• GAAP acquired in-process research and development expense was $803.7 million, compared to $0.0 million in the same quarter last year, related exclusively to the value of the in-process research and development asset acquired in connection with the Wilson Therapeutics AB acquisition completed in the second quarter of 2018.
• GAAP income tax expense was $38.8 million, compared to $41.1 million in the same quarter last year. Non-GAAP income tax expense was $77.1 million, compared to $53.4 million in the same quarter last year.
• GAAP diluted EPS was $(2.05) per share, inclusive of $803.7 million of expense related to the value of the in-process research and development asset acquired in connection with the Wilson Therapeutics AB acquisition, compared to $0.73 per share in the same quarter last year. Non-GAAP diluted EPS was $2.07 per share, compared to $1.56 per share in the second quarter of 2017.

• ALXN1210- Paroxysmal Nocturnal Hemoglobinuria (PNH): Alexion submitted applications in the U.S. and the EU for the approval of ALXN1210 in patients with PNH. These submissions are based on previously announced positive results from Phase 3 studies of ALXN1210 in complement inhibitor treatment-naive patients and in patients who switched from Soliris^® to ALXN1210. In both studies, which collectively comprise the largest ever clinical program in PNH, ALXN1210 administered intravenously every eight weeks, demonstrated non-inferiority to Soliris^® administered intravenously every two weeks, on all 11 primary and key secondary endpoints. Alexion also plans to file for regulatory approval in Japan later this year. In addition, a Phase 3 study of ALXN1210 in children and adolescents with PNH is currently underway.
• ALXN1210- Atypical Hemolytic Uremic Syndrome (aHUS): Enrollment was completed in late May 2018 in a Phase 3 trial of ALXN1210 administered intravenously every eight weeks in complement inhibitor treatment-naive adolescent and adult patients with aHUS. Data from this study are now expected in early 2019. Alexion intends to file for regulatory approval in aHUS following approval of ALXN1210 in PNH. A Phase 3 study of ALXN1210 in children with aHUS is currently underway.
• ALXN1210- Subcutaneous: In late 2018, Alexion plans to initiate a single, PK-based Phase 3 study of ALXN1210 delivered subcutaneously once per week to support registration in PNH and aHUS.
• ALXN1810- Subcutaneous: Alexion filed a Clinical Trial Application (CTA) in the EU for subcutaneous ALXN1210 co-administered with Halozyme's ENHANZE^® drug-delivery technology, PH20, and plans to initiate a Phase 1 study in the second half of 2018. Pending co-formulation data, this next-generation subcutaneous formulation will be called ALXN1810 and has the potential to further extend the dosing interval to once every two weeks or once per month.
• Soliris^® (eculizumab)- Relapsing Neuromyelitis Optica Spectrum Disorder (NMOSD): Enrollment was completed in October 2017 in the PREVENT study, a single, multinational, placebo-controlled Phase 3 trial of Soliris^® in patients with NMOSD; Alexion expects to report data by the end of 2018.
• WTX101- Wilson Disease: In the second quarter, Alexion announced the closing of the tender period for the acquisition of Wilson Therapeutics AB, a biopharmaceutical company, based in Stockholm, Sweden, that developed novel therapies for patients with rare copper-mediated disorders, and assumed control of the company. WTX101 is in Phase 3 development as a treatment for Wilson disease, a rare genetic disorder with devastating hepatic and neurological consequences. WTX101 is a first-in-class oral copper-binding agent with a unique mechanism of action to access and bind to serum copper and promote its removal from the liver.
• CP010- Complement Pharma: In the second quarter, Alexion began a collaboration with Complement Pharma to co-develop CP010, a preclinical C6 inhibitor that has the potential to treat multiple neurological disorders.

• A foreign currency tailwind, net of hedging activities, of approximately $25 million.
• Unfavorable Soliris^® revenue impact of $90 to $110 million from ALXN1210 and other clinical trial recruitment versus prior year.
• $803.7 million of expense related to the value of the in-process research and development asset acquired in connection with Wilson Therapeutics AB.
• GAAP effective tax rate of 39 to 40 percent; non-GAAP effective tax rate of 14.5 to 15.5 percent.

Alexion's financial guidance is based on current foreign exchange rates net of hedging activities and does not include the effect of acquisitions, license and collaboration agreements, intangible asset impairments, litigation charges, changes in fair value of contingent consideration or restructuring and related activity outside of the previously announced activities that may occur after the day prior to the date of this press release.

Alexion will host a conference call/audio webcast to discuss the second quarter 2018 results today at 8:00 a.m. Eastern Time. To participate in the call, dial 866-762-3111 (USA) or 210-874-7712 (International), conference ID 9096048 shortly before 8:00 a.m. Eastern Time. A replay of the call will be available for a limited period following the call. The audio webcast can be accessed on the Investor page of Alexion's website at: http://ir.alexion.com.

Alexion is a global biopharmaceutical company focused on serving patients and families affected by rare diseases through the discovery, development and commercialization of life-changing therapies. As the global leader in complement biology and inhibition for more than 20 years, Alexion has developed and commercializes the first and only approved complement inhibitor to treat patients with paroxysmal nocturnal hemoglobinuria (PNH), atypical hemolytic uremic syndrome (aHUS), and anti-acetylcholine receptor (AchR) antibody-positive generalized myasthenia gravis (gMG). Alexion also has two highly innovative enzyme replacement therapies for patients with life-threatening and ultra-rare metabolic disorders, hypophosphatasia (HPP) and lysosomal acid lipase deficiency (LAL-D). In addition, the company is developing two late-stage therapies, a second complement inhibitor and a copper-binding agent for Wilson disease. Alexion focuses its research efforts on novel molecules and targets in the complement cascade and its development efforts on the core therapeutic areas of hematology, nephrology, neurology, and metabolic disorders. Alexion has been named to the Forbes list of the World's Most Innovative Companies seven years in a row and is headquartered in Boston, Massachusetts' Innovation District. The company also has offices around the globe and serves patients in more than 50 countries. This press release and further information about Alexion can be found at: www.alexion.com.

This press release contains forward-looking statements for purposes of the Private Securities Litigation Reform Act of 1995, including statements related to updated guidance regarding anticipated financial results for 2018 (and the assumptions related to such guidance), Alexion's development plans for ALXN1210 (including the goal of improving the standard of care), the potential medical benefits of ALXN1210 for the treatment of PNH, Alexion's future clinical, regulatory, and commercial plans for ALXN1210 (including the plan to launch as a treatment for PNH next year), goal of building out the clinical pipeline, the completion and timing for the release of information from studies and clinical trials, plans and timing for regulatory filings and clinical programs for our other product candidates, potential benefits of ALXN1810, CP010 and other product candidates, future potential expenses related to restructuring efforts; and the timing and potential benefits of the acquisition of Wilson Therapeutics. Forward-looking statements are subject to factors that may cause Alexion's results and plans to differ materially from those forward-looking statements, including for example, decisions of regulatory authorities regarding the adequacy of our research, marketing approval or material limitations on the marketing of our products, delays, failure of product candidates to obtain regulatory approval, delays or the inability to launch product candidates due to regulatory restrictions, anticipated expense or other matters, interruptions or failures in the manufacture and supply of our products and our product candidates, failure to satisfactorily address matters raised by the FDA and other regulatory agencies, the possibility that results of clinical trials are not predictive of safety and efficacy results of our products in broader patient populations, the possibility that current rates of adoption of Soliris^® in PNH, aHUS or other diseases are not sustained, the possibility that clinical trials of our product candidates could be delayed or terminated prior to completion, the adequacy of our pharmacovigilance and drug safety reporting processes, the risk that third party payors (including governmental agencies) will not reimburse or continue to reimburse for the use of our products at acceptable rates or at all, the possibility that expected tax benefits will not be realized, assessment of impact of recent accounting pronouncements, potential declines in sovereign credit ratings or sovereign defaults in countries where we sell our products, delay of collection or reduction in reimbursement due to adverse economic conditions or changes in government and private insurer regulations and approaches to reimbursement, uncertainties surrounding legal proceedings, company investigations and government investigations, including investigations of Alexion by the U.S. Securities and Exchange Commission (SEC) and U.S. Department of Justice, the risk that anticipated regulatory filings are delayed, the risk that estimates regarding the number of patients with PNH, aHUS, gMG, HPP and LAL-D are inaccurate, the risks of changing foreign exchange rates, risks relating to the potential effects of the Company's restructuring and relocation of its corporate headquarters, risks related to the acquisition of Wilson Therapeutics and the co-development with Complement Pharma, and a variety of other risks set forth from time to time in Alexion's filings with the SEC, including but not limited to the risks discussed in Alexion's Quarterly Report on Form 10-Q for the period ended March 31, 2018 and in our other filings with the SEC. Alexion disclaims any obligation to update any of these forward-looking statements to reflect events or circumstances after the date hereof, except when a duty arises under law.

In addition to financial information prepared in accordance with GAAP, this press release also contains non-GAAP financial measures that Alexion believes, when considered together with the GAAP information, provide investors and management with supplemental information relating to performance, trends and prospects that promote a more complete understanding of our operating results and financial position during different periods. The non-GAAP results exclude the impact of the following GAAP items: share-based compensation expense, fair value adjustment of inventory acquired, amortization of purchased intangible assets, changes in fair value of contingent consideration, acquisition-related costs, restructuring and related expenses, upfront payments related to licenses and collaborations, acquired in-process research and development assets, impairment of intangible assets, change in value of equity securities without readily determinable fair values, litigation charges and certain adjustments to income tax expense. These non-GAAP financial measures are not intended to be considered in isolation or as a substitute for, or superior to, the financial measures prepared and presented in accordance with GAAP, and should be reviewed in conjunction with the relevant GAAP financial measures. Please refer to the attached Reconciliations of GAAP to non-GAAP Financial Results and GAAP to non-GAAP 2018 Financial Guidance for explanations of the amounts adjusted to arrive at non-GAAP net income and non-GAAP earnings per share amounts for the three and six month periods ended June 30, 2018 and 2017 and projected twelve months ending December 31, 2018.