PK, Safety, and Tolerability Study of RBP-7000 of Different Molecular Weight Polymer in Subjects With Schizophrenia

A Multicenter, Randomized, Open-Label, Single-Dose Study to Evaluate the Pharmacokinetics, Safety, and Tolerability of RBP-7000 Using Poly (DL-lactide-co-glycolide) Polymer of Two Different Molecular Weights (Low and High Molecular Weights as Test Treatments) Compared to Intermediate Molecular Weight (Reference Treatment) Polymer in Subjects With Schizophrenia

Primary Objective: To assess the relative bioavailability of RBP-7000 formulated with 2 different molecular weights (MW) (low and high MW as test treatments) of poly (DL-lactide-co-glycolide) with a carboxylic acid end group (PLGH) polymer compared to intermediate MW PLGH polymer following single subcutaneous (SC) injection of RBP-7000 in subjects with stable schizophrenia.

Secondary Objective:

To evaluate the safety and tolerability of single SC injections of RBP-7000 using a PLGH polymer of 2 different MW (low and high MW as test treatments) compared to intermediate MW polymer in subjects with stable schizophrenia.

This is a multicenter, randomized, open-label, single-dose, parallel-group study in subjects with clinically stable schizophrenia who are not currently taking risperidone. A total of approximately 48 subjects (16 per group) will be randomized to receive a single subcutaneous (SC) injection of RBP-7000 120 mg formulated with PLGH polymer of either 21 kilodaltons (kDa) (low MW group), 29 kDa of PLGH polymer (high MW group), or 26 kDa of PLGH polymer (intermediate MW group).

Inclusion Criteria:

• Diagnosis of schizophrenia as defined by DSM-5 criteria.
• Clinically stable schizophrenia, as evidenced by the investigator evaluation, outpatient status for at least 30 days prior to screening, and confirmation of stability by a caregiver who has regular supportive contact with the subject.
• Otherwise healthy on the basis of physical examination.
• Body mass index (BMI) between 18 and 35 kg/m^2 and weight of at least 49.9 kg at screening.

Exclusion Criteria:

• Subjects taking any oral risperidone product (except the test doses of 0.25 mg of risperidone); or subjects taking any risperidone or 9-hydroxyrisperidone sustained-release or depot formulation within 120 days prior to study screening; or subjects who have received the 3-month depot formulation of 9-hydroxyrisperidone within 2 years of study screening.
• Subjects taking a clinically relevant inducer or inhibitor of cytochrome P450 (CYP) 2D6, or CYP3A4, who have not undergone proper washout (minimum of 5 half-lives of the medication) of this prohibited medication prior to Day 1.
• Medications, which in the opinion of the Investigator in conjunction with the medical monitor, may be expected to significantly interfere with metabolism or excretion of risperidone and/or 9-hydroxyrisperidone; may be associated with a significant drug interaction with risperidone; or may pose a significant risk to a subject's participation in the study.
• Any natural products or herbal preparations including all vitamins and supplements throughout the study.
• Subjects with a history of cancer unless disease-free for ≥5 years (with the exception of resected basal cell or squamous cell carcinoma of the skin).
• Subjects with any other active medical condition/disorder/disease that may either compromise subject safety or interfere with the safety and/or outcome evaluation of the study drug.
• Subjects that had an exacerbation of schizophrenia in the last 30 days.
• Subjects with evidence or history (in the past 6 months prior to screening) of a significant hepatic disorder that may either compromise subject safety or interfere with the safety and/or outcome evaluation of the study drug, including:
• Acute or chronic hepatitis, including but not limited to hepatitis B or C.
• Total bilirubin >1.5 x the upper limit of normal (ULN), or
• Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) >2x ULN.
• Subjects with a history of severe renal disease, or creatinine clearance <60 mL/min
• Subjects with evidence or history of orthostatic hypotension within 6 months of screening.
• Subjects with absolute neutrophil count <1.5x 10^9/L (African and African/American <1.2x 10^9/L).
• Subjects with a history of drug-induced leucopenia.
• Subjects who have acquired immune deficiency syndrome (AIDS) or to be human immunodeficiency virus (HIV)-positive.
• Subjects with other medical conditions including, but not limited to, history of heart attack (myocardial infarction) or brain injury (traumatic injury with loss of consciousness and/or cerebrovascular accident), or clinically significant low blood pressure or arrhythmias as interpreted by the Principal Investigator or medically qualified sub-investigator.
• Subjects with congenital long QT syndrome, history of prolonged QT in the 3 months prior to screening, or a corrected QT interval (Fridericia - QTcF) >450 msec (male) or >470 msec (female) at screening (Visit 1).
• Subjects with suicidal ideation with intent or plan
• Subjects with uncontrolled depression, in the opinion of the Investigator.
• Subjects with a diagnosis of insulin-dependent diabetes, or who have a hemoglobin A1c (HbA1c) ≥8.0% at screening, or have had changes in diabetic medication regimen in the 28 days prior to signing the informed consent document.
• Subjects with prior allergic reactions, sensitivities or other known contraindications to any component of RBP-7000 (e.g., risperidone, PLGH or NMP).
• Women of childbearing potential who are pregnant or breastfeeding, seeking pregnancy, or failing to use adequate contraceptive methods during the study.
• Subjects with the presence of opioids, cocaine, amphetamines, methadone, barbiturates, benzodiazepines, methamphetamines, cannabinoids, or phencyclidine in the urine as assessed by a urine drug screen.
• Subjects with epilepsy or other seizure disorders, Parkinson's disease or dementia.