AB Biosciences and Shire Enter Into Agreement for Development and Commercialization of AB Biosciences' PRIM Program

AB Biosciences and Shire Enter Into Agreement for Development and Commercialization of AB Biosciences' PRIM Program for Potential Treatment of Autoimmune Diseases and Other Immune-Mediated Disorders

AB Biosciences to Receive an Upfront License Fee and Potential Research, Development and Commercial Milestone Payments from Shire

Shire Receives Exclusive Worldwide License to Develop and Commercialize PRIM Program

Allston, Mass., and Cambridge, Mass, January 30, 2018 - AB Biosciences, Inc. and Shire plc (LSE: SHP, NASDAQ: SHPG), the global biotechnology leader in rare diseases, today announced that they have entered into an agreement granting Shire an exclusive worldwide license to develop and commercialize AB Biosciences' pan receptor interacting molecule (PRIM) program, which uses AB Biosciences' proprietary oligomeric Fc technology platform. PRIM, a recombinant immunoglobulin product candidate, has shown encouraging preclinical data, including enhanced biological activity relative to currently approved intravenous immunoglobulin (IVIg) therapies, in preclinical models of autoimmune and inflammatory diseases.

"This agreement provides the opportunity to accelerate the development of the PRIM program and potentially benefit patients with autoimmune and inflammatory disorders that are currently treated with the traditional human IVIg preparations," said Yen-Ming Hsu, Ph.D., President and Chief Executive Officer of AB Biosciences, Inc. "As a global biotech leader in the development and commercialization of biologic therapeutics, Shire is the ideal development and commercialization partner for our innovative PRIM program, particularly given their proven developmental expertise and continuing success in their IVIg commercial franchise."

"AB Biosciences has demonstrated innovation in the area of antibody technology and protein design, and Shire is pleased to continue to advance this program," said Andreas Busch, Ph.D., Head of Research and Development and Chief Scientific Officer at Shire. "The novel design of this investigational antibody-derived recombinant protein therapeutic and promising biological activity demonstrated in preclinical models makes the PRIM program an exciting opportunity for Shire to further expand its leadership and commitment to treating patients with autoimmune disorders."

Under the terms of the agreement, AB Biosciences will grant Shire an exclusive, worldwide license to its intellectual property relating to its PRIM program. AB Biosciences will receive an upfront license fee payment from Shire and is eligible to receive contingent research, development, and commercialization milestone payments as well as royalty payments. No further terms of the agreement were disclosed.

About PRIM

PRIM (pan receptor interacting molecule) is a novel protein therapeutic for the treatment of autoimmune disorders. Preparation of human IVIg contains immune complexes which in turn contain multiple antibody and antigen molecules that are known to modulate immune responses through their interactions with Fc receptors. PRIM protein contains three immunoglobulin constant regions and can effectively bind to Fc receptors similar to that of immune complexes. In contrast to human IVIg, production of PRIM protein does not require the traditional plasma collection of thousands of individuals and safety tests for infectious agents. Furthermore, without the bulk of monomeric immunoglobulin, PRIM has the potential to be biologically active at lower doses. As such, alternative, non-intravenous routes of administration may be feasible.

For further information please contact:

NOTES TO EDITORS

About AB Biosciences

AB Biosciences (ABB) is dedicated to the upstream R&D of novel biologics for diagnostic and therapeutic applications. With solid core competence in viral-mediated gene transfer, immunobiology and protein engineering, ABB has streamlined an efficient technological platform to accelerate the discovery and developmental processes for acquiring the proof-of-concept data packages prior to seeking partnership for new drug development from the biologics.  Specifically, ABB is focusing on developing immunoglobulin-based biologics for immunological, oncological and neurological indications. For more information, please visit www.abbiosciences.com.

About Shire

Shire is the global leader in serving patients with rare diseases. We strive to develop best-in-class therapies across a core of rare disease areas including hematology, immunology, genetic diseases, neuroscience, and internal medicine with growing therapeutic areas in ophthalmics and oncology. Our diversified capabilities enable us to reach patients in more than 100 countries who are struggling to live their lives to the fullest.

We feel a strong sense of urgency to address unmet medical needs and work tirelessly to improve people's lives with medicines that have a meaningful impact on patients and all who support them on their journey.

www.shire.com

Shire Forward-Looking Statements

Statements included herein that are not historical facts, including without limitation statements concerning future strategy, plans, objectives, expectations and intentions, projected revenues, the anticipated timing of clinical trials and approvals for, and the commercial potential of, inline or pipeline products, are forward-looking statements. Such forward-looking statements involve a number of risks and uncertainties and are subject to change at any time. In the event such risks or uncertainties materialize, Shire's results could be materially adversely affected. The risks and uncertainties include, but are not limited to, the following:

• Shire's products may not be a commercial success;
• increased pricing pressures and limits on patient access as a result of governmental regulations and market developments may affect Shire's future revenues, financial condition and results of operations;
• Shire conducts its own manufacturing operations for certain of its products and is reliant on third party contract manufacturers to manufacture other products and to provide goods and services. Some of Shire's products or ingredients are only available from a single approved source for manufacture. Any disruption to the supply chain for any of Shire's products may result in Shire being unable to continue marketing or developing a product or may result in Shire being unable to do so on a commercially viable basis for some period of time;
• the manufacture of Shire's products is subject to extensive oversight by various regulatory agencies. Regulatory approvals or interventions associated with changes to manufacturing sites, ingredients or manufacturing processes could lead to, among other things, significant delays, an increase in operating costs, lost product sales, an interruption of research activities or the delay of new product launches;
• certain of Shire's therapies involve lengthy and complex processes, which may prevent Shire from timely responding to market forces and effectively managing its production capacity;
• Shire has a portfolio of products in various stages of research and development. The successful development of these products is highly uncertain and requires significant expenditures and time, and there is no guarantee that these products will receive regulatory approval;
• the actions of certain customers could affect Shire's ability to sell or market products profitably. Fluctuations in buying or distribution patterns by such customers can adversely affect Shire's revenues, financial conditions or results of operations;
• Shire's products and product candidates face substantial competition in the product markets in which it operates, including competition from generics;
• adverse outcomes in legal matters, tax audits and other disputes, including Shire's ability to enforce and defend patents and other intellectual property rights required for its business, could have a material adverse effect on the Company's revenues, financial condition or results of operations;
• inability to successfully compete for highly qualified personnel from other companies and organizations;
• failure to achieve the strategic objectives, including expected operating efficiencies, cost savings, revenue enhancements, synergies or other benefits at the time anticipated or at all with respect to Shire's acquisitions, including NPS Pharmaceuticals Inc., Dyax Corp. or Baxalta Incorporated may adversely affect Shire's financial condition and results of operations;
• Shire's growth strategy depends in part upon its ability to expand its product portfolio through external collaborations, which, if unsuccessful, may adversely affect the development and sale of its products;
• a slowdown of global economic growth, or economic instability of countries in which Shire does business, as well as changes in foreign currency exchange rates and interest rates, that adversely impact the availability and cost of credit and customer purchasing and payment patterns, including the collectability of customer accounts receivable;
• failure of a marketed product to work effectively or if such a product is the cause of adverse side effects could result in damage to Shire's reputation, the withdrawal of the product and legal action against Shire;
• investigations or enforcement action by regulatory authorities or law enforcement agencies relating to Shire's activities in the highly regulated markets in which it operates may result in significant legal costs and the payment of substantial compensation or fines;
• Shire is dependent on information technology and its systems and infrastructure face certain risks, including from service disruptions, the loss of sensitive or confidential information, cyber-attacks and other security breaches or data leakages that could have a material adverse effect on Shire's revenues, financial condition or results of operations;
• Shire incurred substantial additional indebtedness to finance the Baxalta acquisition, which has increased its borrowing costs and may decrease its business flexibility;
• Our ongoing strategic review of our Neuroscience franchise may distract management and employees and may not lead to improved operating performance or financial results; there can be no guarantee that, once completed, our strategic review will result in any additional strategic changes beyond those that have already been announced; and

a further list and description of risks, uncertainties and other matters can be found in Shire's most recent Annual Report on Form 10-K and in Shire's subsequent Quarterly Reports on Form 10-Q, in each case including those risks outlined in "ITEM 1A: Risk Factors", and in Shire's subsequent reports on Form 8-K and other Securities and Exchange Commission filings, all of which are available on Shire's website.

All forward-looking statements attributable to us or any person acting on our behalf are expressly qualified in their entirety by this cautionary statement. Readers are cautioned not to place undue reliance on these forward-looking statements that speak only as of the date hereof. Except to the extent otherwise required by applicable law, we do not undertake any obligation to update or revise forward-looking statements, whether as a result of new information, future events or otherwise.