AB Science issues a corrective press release regarding adverse events information from study AB09004 reported on December 16, 2020

PRESS RELEASE

AB SCIENCE ISSUES A CORRECTIVE PRESS RELEASE

Paris, December 17, 2020, 8am CET

AB Science SA (Euronext - FR0010557264 - AB) today announced that the press release issued on December 16, 2020 regarding the results from study AB09004, which evaluated masitinib in the treatment of Alzheimer disease, contained a material error in the adverse events information reported.

The percentage of adverse events observed in study AB09004 study comparing the efficacy and safety of masitinib relative to placebo after 24 weeks of treatment when administered as an add-on therapy to cholinesterase inhibitor (donepezil, rivastigmine or galantamine) and/or memantine, were the following with masitinib 4.5 mg/kg/day:

• 87.0 % of patients had at least one adverse event in the masitinib arm versus 77.5 % in the control arm
• 13.0 % of patients had at least one serious adverse event (non-fatal) in the masitinib arm versus 5.4 % in the control arm
• 26.5 % of patients had at least one severe adverse event in the masitinib arm versus 19.3 % in the control arm

The results of the efficacy analysis remain unchanged.

About masitinib
Masitinib is a new orally administered tyrosine kinase inhibitor that targets mast cells and macrophages, important cells for immunity, through inhibiting a limited number of kinases. Based on its unique mechanism of action, masitinib can be developed in a large number of conditions in oncology, in inflammatory diseases, and in certain diseases of the central nervous system. In oncology due to its immunotherapy effect, masitinib can have an effect on survival, alone or in combination with chemotherapy. Through its activity on mast cells and microglia and consequently the inhibition of the activation of the inflammatory process, masitinib can have an effect on the symptoms associated with some inflammatory and central nervous system diseases and the degeneration of these diseases.

About AB Science
Founded in 2001, AB Science is a pharmaceutical company specializing in the research, development and commercialization of protein kinase inhibitors (PKIs), a class of targeted proteins whose action are key in signaling pathways within cells. Our programs target only diseases with high unmet medical needs, often lethal with short term survival or rare or refractory to previous line of treatment.
AB Science has developed a proprietary portfolio of molecules and the Company’s lead compound, masitinib, has already been registered for veterinary medicine and is developed in human medicine in oncology, neurological diseases, and inflammatory diseases. The company is headquartered in Paris, France, and listed on Euronext Paris (ticker: AB).

Further information is available on AB Science’s website: www.ab-science.com.

Forward-looking Statements - AB Science
This press release contains forward-looking statements. These statements are not historical facts. These statements include projections and estimates as well as the assumptions on which they are based, statements based on projects, objectives, intentions and expectations regarding financial results, events, operations, future services, product development and their potential or future performance.

These forward-looking statements can often be identified by the words "expect", "anticipate", "believe", "intend", "estimate" or "plan" as well as other similar terms. While AB Science believes these forward-looking statements are reasonable, investors are cautioned that these forward-looking statements are subject to numerous risks and uncertainties that are difficult to predict and generally beyond the control of AB Science and which may imply that results and actual events significantly differ from those expressed, induced or anticipated in the forward-looking information and statements. These risks and uncertainties include the uncertainties related to product development of the Company which may not be successful or to the marketing authorizations granted by competent authorities or, more generally, any factors that may affect marketing capacity of the products developed by AB Science, as well as those developed or identified in the public documents filed by AB Science with the Autorité des Marchés Financiers (AMF), including those listed in the Chapter 4 "Risk Factors" of AB Science reference document filed with the AMF on November 22, 2016, under the number R. 16-078. AB Science disclaims any obligation or undertaking to update the forward-looking information and statements, subject to the applicable regulations, in particular articles 223-1 et seq. of the AMF General Regulations.

For additional information, please contact:

AB Science
Financial Communication & Media Relations
[e-mail]

Media Relations – USA

RooneyPartners
Jeffrey Freedman
[e-mail]

[phone]

Media Relations – France

NewCap
Arthur Rouillé
[e-mail]

[phone]

Attachment

• PR_AB Science_17.12.2020 vEng