 - MTX dose of 0.2 mgkg, up to 5 mg, once weekly, either SC, IM, or orally for subjects whose body weight is 20 kg, or a dose that is the highest tolerated for the subject, in the opinion of the investigator for example due to leukopenia, elevated liver enzymes, nausea, etc. for at least 8 weeks prior to Baseline with a stable dose for at least 4 weeks prior to Baseline. 