Recent research indicates that two popular arthritis drugs are possibly not as safe as they initially believed.
                    
                
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                Athat two popular arthritis drugs are possibly not as safe as they initially believed
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                Bthat two popular arthritis drugs may not be as safe as they were initially believed to be
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                Ctwo popular arthritis drugs to possibly not be as safe as it was initially believed
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                Dthe safety of two popular arthritis drugs may not be as great as it was initially believed
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                Ethe safety of two popular arthritis drugs not to be as great as they were initially believed to be
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