MedPath

Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of RDX5791 in Healthy Volunteers

Phase 1
Completed
Conditions
Healthy
Interventions
Drug: Placebo
Registration Number
NCT02819687
Lead Sponsor
Ardelyx
Brief Summary

A Phase I, single-center, randomized, double-blind, placebo-controlled study to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of single-and multiple-ascending doses of RDX5791 in healthy male and female subjects.

Detailed Description

In the single-ascending dose (SAD), 5 separate cohorts received RDX5791 at various doses once po fasting. Each cohort of 8 subjects (6 RDX5791, 2 placebo) received a diet standardized fro Na+ content wile in the clinical pharmacology unit (CPU).

The PK data from the 50-mg dose and the safety data from the 150-mg dose of the SAD study were evaluated prior to proceeding with the multiple-ascending dose (MAD) phase. Doses of RDX5791 are 3, 10, 30, and 100 mg administered once daily po fasting. Four cohorts of 10 subjects each (8 RDX5791, 2 placebo) received a diet standardized for Na+ content while in the CPU.

Safety assessments including clinical assessment and vital signs, clinical laboratory evaluations, ECGs, and AE monitoring were performed at regular intervals. Plasma was collected at regular intervals for PK analysis. The PD assessment included stool frequency and consistency, as well as changes in urinary Na+ excretion. All bowel movements were collected and analyzed for Na+ content outside this study protocol.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
80
Inclusion Criteria
  • BMI between 18 and 29.9 kg/m², inclusive
  • Females must be of non-childbearing potential; If of child-bearing potential, must have negative pregnancy test and confirm the use of one of the appropriate means of contraception
  • Males must agree to use appropriate methods of barrier contraception or have documented surgical sterilization
Exclusion Criteria
  • Diagnosis or treatment of any clinically symptomatic biochemical or structural abnormality of the GI tract
  • Any surgery on the small intestine or colon, excluding appendectomy
  • Loose stools (Bristol Stool Form Score of 6 or 7) ≥2 days in the past 7 days
  • Hepatic dysfunction ([ALT] or [AST]) >1.5 times the upper limit of normal or renal impairment
  • Any evidence of or treatment of malignancy, excluding non-melanomatous malignancies of the skin
  • Use of diuretic medications, medications that are known to affect stool consistency and/or GI motility
  • Use of an investigational agent within 30 days prior to Day -2
  • Positive virology, alcohol, or drugs of abuse test during screening
  • Use of any prescription medication within 7 days before admission to the CPU
  • Have had significant blood loss (>450 mL) or have donated 1 or more units of blood or plasma within 8 weeks prior to study entry

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
RDX5791 150mg QD (SAD phase)Placebo150mg of RDX5791 administered once daily PO fasting
RDX5791 450mg QD (SAD phase)RDX5791450mg of RDX5791 administered once daily PO fasting
RDX5791 450mg QD (SAD phase)Placebo450mg of RDX5791 administered once daily PO fasting
RDX5791 900mg QD (SAD phase)RDX5791900mg of RDX5791 administered once daily PO fasting
RDX5791 50mg QD (SAD phase)Placebo50mg of RDX5791 administered once daily PO fasting
RDX5791 150mg QD (SAD phase)RDX5791150mg of RDX5791 administered once daily PO fasting
RDX5791 50mg QD (SAD phase)RDX579150mg of RDX5791 administered once daily PO fasting
RDX5791 10mg QD (SAD phase)RDX579110mg of RDX5791 administered once daily PO fasting
RDX5791 10mg QD (SAD phase)Placebo10mg of RDX5791 administered once daily PO fasting
RDX5791 900mg QD (SAD phase)Placebo900mg of RDX5791 administered once daily PO fasting
RDX5791 3mg QD (MAD phase)RDX57913mg of RDX5791 administered once daily PO fasting
RDX5791 3mg QD (MAD phase)Placebo3mg of RDX5791 administered once daily PO fasting
RDX5791 10mg QD (MAD phase)RDX579110mg of RDX5791 administered once daily PO fasting
RDX5791 10mg QD (MAD phase)Placebo10mg of RDX5791 administered once daily PO fasting
RDX5791 30 mg QD (MAD phase)RDX579130mg of RDX5791 administered once daily PO fasting
RDX5791 30 mg QD (MAD phase)Placebo30mg of RDX5791 administered once daily PO fasting
RDX5791 100 mg QD (MAD phase)RDX5791100mg of RDX5791 administered once daily PO fasting
RDX5791 100 mg QD (MAD phase)Placebo100mg of RDX5791 administered once daily PO fasting
Primary Outcome Measures
NameTimeMethod
Adverse events7 days

serum chemistry and hematology, ECGs, and clinical signs and symptoms

Secondary Outcome Measures
NameTimeMethod
Pharmacokinetics of RDX57917 days

blood levels of drug

Urinary and fecal sodium levels7 days

to assess the pharmacodynamics of RDX5791

Urinary and fecal phosphorus levels7 days

to assess the pharmacodynamics of RDX5791

© Copyright 2025. All Rights Reserved by MedPath