8. All patients must confirm the diagnosis of asthma by bronchodilator reversibility at Visit 1, resulting in an increase in FEV1 of = 12% and = 200 mL 15 to 30 minutes after 400 µg salbutamol (albuterol). If patients in the lower age range (e.g. 12 to 14 year old patients) exhibit a very small total lung volume, positive reversibility testing might be based solely on the relative (=12%) post-bronchodilator response.