Objective: To assess ADHD symptoms after switching from Methylphenidate Immediate-release (MPH-IR) to Methylphenidate Spheroidal Oral Drug Absorption System (MPH-SODAS) in clinically stable patients with ADHD and to identify predictors of dissatisfaction with MPH-SODAS.
Methods: This is an 8-week open clinical trial. Patients were assigned to MPH-SODAS according to their pre-study dose of MPH-IR. Assessments at baseline were conducted using the Swanson, Nolan, and Pelham-IV Questionnaire (SNAP-IV), and the Barkley's Side Effect Rating Scale (SERS). Potentials predictors of treatment response were evaluated.
Results: From 62 patients, 47 completed the protocol. There was no significant change in the total score at the SNAP-IV (F (1,51.26) = 0.01; P = 0.91) and its subscales scores during the trial. Although no significant effect on the SERS total score (F (1,111.49) = 0.75; P = 0.39) was found, one adult patient with a previous cardiovascular condition presented a hemorrhagic cerebral vascular accident resulting in her obit. Overall, 46 (74.2%) patients reported to be satisfied. No factor assessed predicted dissatisfaction in univariated analyses.
Conclusion: Results suggested that switching from MPH-IR to MPH-SODAS did not affect stabilization of ADHD symptoms in the majority of patients. MPH prescription in patients with previous cardiovascular conditions must be extremely careful. Further studies with long-acting MPH including larger samples and patients not responsive to MPH-IR are needed especially in countries outside the US.