Emergent BioSolutions Announces Acceptance of Otlertuzumab Abstracts for Presentation at 2013 American Society of Hematology Annual Meeting

Emergent BioSolutions Inc. (NYSE: EBS) announced today that two abstracts on its humanized anti-CD37 mono-specific protein therapeutic, otlertuzumab (TRU-016), being evaluated in patients with chronic lymphocytic leukemia (CLL), have been accepted for presentation at the 55^th Annual Meeting of the American Society of Hematology (ASH) on December 7-10, 2013 in New Orleans, Louisiana. The abstracts are available on the ASH website at www.hematology.org.

“We are encouraged by the otlertuzumab data accepted for presentation at ASH,” said Scott C. Stromatt, M.D., senior vice president and chief medical officer, Emergent BioSolutions. “Data suggest that otlertuzumab could be a good candidate for utilization as part of combination therapies. We look forward to the presentation of the study results evaluating otlertuzumab both in patients with relapsed CLL as well as patients with previously untreated CLL.”

POSTER 2860: Phase 2 Study of Otlertuzumab (TRU-016), an Anti-CD37 ADAPTIR^TM Protein, in Combination with Bendamustine vs. Bendamustine Alone in Patients with Relapsed Chronic Lymphocytic Leukemia

POSTER 4165: Phase 1b Study of Otlertuzumab (TRU-016), an Anti-CD37 ADAPTIR^TM Protein, in Combination with Rituximab in Patients with Previously Untreated Chronic Lymphocytic Leukemia

About Emergent BioSolutions

Emergent BioSolutions is a specialty pharmaceutical company seeking to protect and enhance life by offering specialized products to healthcare providers and governments to address medical needs and emerging health threats. Additional information about the company may be found at www.emergentbiosolutions.com. Follow us @emergentbiosolu.

Safe Harbor Statement

This press release includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Any statements, other than statements of historical fact, are forward-looking statements. Forward-looking statements in this press release include statements about the potential and therapeutic opportunity of otlertuzumab. These forward-looking statements are based on our current intentions, beliefs and expectations regarding future events. We cannot guarantee that any forward-looking statement will be accurate. Investors should realize that if underlying assumptions prove inaccurate or unknown risks or uncertainties materialize, actual results could differ materially from our expectations. Investors are, therefore, cautioned not to place undue reliance on any forward-looking statement. Any forward-looking statement speaks only as of the date of this press release, and, except as required by law, we do not undertake to update any forward-looking statement to reflect new information, events or circumstances.

There are a number of important factors that could cause the company’s actual results to differ materially from those indicated by such forward-looking statements, including the success of our ongoing and planned clinical trials; the rate and degree of market acceptance and clinical utility of our products; the timing of and our ability to obtain and maintain regulatory approvals for our product candidates; and our commercialization, marketing and manufacturing capabilities and strategy. The foregoing sets forth many, but not all, of the factors that could cause actual results to differ from our expectations in any forward-looking statement. Investors should consider this cautionary statement, as well as the risk factors identified in our periodic reports filed with the SEC, when evaluating our forward-looking statements.