AB Science announces cessation of its rheumatoid arthritis study in order to focus on clinical studies with a probability of success greater than 50%


PARIS, Sept. 21, 2015 (GLOBE NEWSWIRE) -- AB Science SA (NYSE Euronext - FR0010557264 - AB), a pharmaceutical company specialized in research, development and marketing of protein kinase inhibitors (PKIs), announces today the decision to stop the phase 3 study of masitinib in rheumatoid arthritis in order to streamline its studies portfolio. This decision has been made following a futility test, conducted by the external Data and Safety Monitoring Board (DSMB), showing that the probability of success on the primary endpoint was below 50% for this study, including the resampling option.

The futility test is based on the study's primary endpoint analysis without resampling and with a conditional power (predictive probability of success) of 20%. For this analysis it is considered that all the patients to be included in the study will follow the trend observed for patients already included at the time of the futility analysis.

If the futility test is successful, the probability of success on the primary endpoint of the study may exceed 20%, without the resampling option.

However, the study protocol includes also a resampling option (the possibility to increase the number of patients enrolled up to a factor two), which can be implemented if an efficacy trend is observed during the interim analysis that needs to be statistically demonstrated by increasing the number of patients in the study. Given the possibility of this option, the probability of success on the primary endpoint of the study can be estimated at 50%, by modifying the study sampling size if the futility test is successful. Alternatively, if the futility test fails, the probability of success on the primary endpoint of the study is below 50% with the resampling option.

The Company policy is to focus on indications with a predictive probability of success greater than 50% and a high medical need.

The number of phase 3 studies initiated, which exceeds ten, makes possible this strategy to focus investments in the most promising indications. In addition, this strategy avoids incurring all the expenditures for a study with a probability of success deemed insufficient.

As a reminder, mastocytosis, severe asthma, amyotrophic lateral sclerosis, progressive multiple sclerosis and Alzheimer's disease meet this dual condition since these diseases all represent unmet medical needs and since the masitinib phase 3 studies in these indications passed the futility test successfully.

Alain Moussy, CEO and co-founder of AB Science stated: "Rheumatoid arthritis is the indication developed with masitinib for which the medical need is the lowest, given the large number of available therapeutic options. The futility test shows a probability of success below 50% with the resampling option. It does not mean that the study cannot be a success, but the probability of success is deemed insufficient according to our internal policy to justify continuation of this investment. That is why we made this decision to stop development in this indication and to focus on indications that have passed the futility test successfully".

The clinical study in rheumatoid arthritis was designed to evaluate the efficacy and safety of masitinib in patients with active rheumatoid arthritis after failure of at least one standard treatment line including at least one biological agent. The primary efficacy measure in this study was the patient rate having an ARC50, which measures a 50% improvement of the disease symptoms.

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 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 in cancers, inflammatory diseases, and central nervous system diseases, both in humans and animal health.

AB Science has developed a proprietary portfolio of molecules and the Company's lead compound, masitinib, has already been registered for veterinary medicine in Europe and in the USA. The company is currently pursuing thirteen phase 3 studies in human medicine in first-line and second-line GIST, metastatic melanoma expressing JM mutation of c-Kit, multiple myeloma, metastatic colorectal cancer, metastatic prostate cancer, pancreatic cancer, T-cell lymphoma, mastocytosis, severe persistent asthma, Alzheimer's disease, progressive forms of multiple sclerosis, and Amyotrophic Lateral Sclerosis. The company is headquartered in Paris, France, and listed on Euronext Paris (ticker: AB).

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

This document contains prospective information. No guarantee can be given as for the realization of these forecasts, which are subject to those risks described in documents deposited by the Company to the Authority of the financial markets, including trends of the economic conjuncture, the financial markets and the markets on which AB Science is present.
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AB Science - Financial Communication & Media Relations
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