Study to Assess the Bioavailability, Pharmacokinetics, Safety, and Tolerability of AVP-923 in Healthy Adult Participants

A Phase 1, Randomized, Single-Dose, 3-Way, Crossover Study to Compare the Relative Bioavailability, Pharmacokinetics, Safety and Tolerability of AVP-923 (Dextromethorphan Hydrobromide and Quinidine Sulfate Capsules) Administered in Applesauce or Via a Nasogastric Feeding Tube With Administration of a Capsule in Healthy Adult Subjects

This study will be conducted to evaluate the relative bioavailability, pharmacokinetics, safety, and tolerability of AVP-923 (dextromethorphan hydrobromide [DM] and quinidine sulfate [Q] capsules) when the contents of a capsule are administered in applesauce or via a nasogastric feeding tube, compared with administration of a capsule in healthy, fasting, adult participants.

This is an open-label, single-center, randomized, single-dose, 3-treatment, 3-period, 6-sequence crossover study in healthy adult participants consisting of approximately 7 weeks of treatment. The study population will be limited to extensive metabolizers of cytochrome P450 (CYP) 2D6.

Approximately 18 participants will be randomly assigned to 1 of 6 sequences (ABC, ACB, BAC, BCA, CAB, CBA).

Inclusion Criteria:

• Healthy adults, 18 to 65 years of age, inclusive
• Willing to sign informed consent form
• Cytochrome P450 2D6 genotype that confers extensive metabolizer profile (as per documented phenotype interpretation from local laboratory and approval from Avanir)

Exclusion Criteria:

• History or presence of significant pulmonary, hepatic, renal, hematologic, allergic, endocrine (including diabetes), immunologic, dermatologic, neurologic (including history or presence of seizures or convulsive disorders), psychiatric disease (including history of suicidal ideation or behavior) or any eating disorder deemed clinically significant by the investigator
• History or presence of significant cardiovascular disease, including complete heart block, QT interval corrected for heart rate (QTc) prolongation, and/or torsades de pointes
• History or presence of any gastrointestinal (GI) disease or condition that could compromise participant safety or affect the absorption of study drug, including GI ulcers, GI bleeding, esophageal or gastric varices, and dyspepsia requiring regular (i.e., more frequently than once a month) use of acid-reducing drugs
• Known hypersensitivity/intolerance to dextromethorphan or quinidine
• Participants whom the principal investigator or his delegate deems to be ineligible