Bupropion as a modulator of drug activity

A method of treating agitation associated with dementia due to Alzheimer's disease in a human patient who is experiencing agitation in Alzheimer's disease (AD), comprising 1) orally administering a first dosage form once daily for one week to the human patient, then administering the first dosage form twice daily to the human patient for one week;

• and 2) then orally administering a second dosage form twice daily to the human patient for at least one week;
• wherein the first dosage form comprises about 30 mg of dextromethorphan hydrobromide, or a molar equivalent amount of another salt form of dextromethorphan or the free base form of dextromethorphan, about 105 mg of bupropion hydrochloride, or a molar equivalent amount of another salt form of bupropion or the free base form of bupropion, and a polymer;
• wherein the second dosage form comprises about 45 mg of dextromethorphan hydrobromide, or a molar equivalent amount of another salt form of dextromethorphan or the free base form of dextromethorphan, and about 105 mg of bupropion hydrochloride, or a molar equivalent amount of another salt form of bupropion or the free base form of bupropion, and a polymer;
• and
• wherein after the human patient has experienced a sustained clinical response as a result of receiving treatment with the first dosage form and the second dosage form, administration of the second dosage form twice daily is continued;
• wherein a sustained clinical response comprises a 30% or greater improvement from baseline in the human patient's Cohen-Mansfield Agitation Inventory (CMAI) total score which is maintained for at least 4 consecutive weeks, and maintaining a Patient Global Impression of Change (PGI-C) score of 3 or less for at least 4 consecutive weeks.