(Sharecast News) - Shire and Shionogi have applied to expand the use in Japan of co-developed drug Intuniv to treat adults for attention deficit hyperactivity disorder. The drug is already approved in the country for children and adolescents but the two companies have completed a Phase 3 clinical trial in the country and claim there is a "significant need" for new non-stimulant treatment options for adults being diagnosed with ADHD.With symptoms including inattention, hyperactivity or impulsivity, ADHD is recognised by the World Health Organisation even though some national surveys have put the prevalence as low 0.6% of the adult population and it has been dismissed by some psychologists as an invented condition.However, tests of 201 adults Japan showed Intuniv, which is a non-stimulant medication, administered once daily resulted in clinicians rating more than twice as many patients taking the drug as "improved" and nearly half of patients as "much improved" or "very much improved". Brigitte Robertson, Shire's head of global clinical development in neuroscience, said the application in Japan for adult use was "a key milestone"."There remains a significant need for new non-stimulant treatment options for adults being diagnosed with ADHD in Japan," she said.