Trial Outcomes & Findings for A Study to Evaluate the Pharmacokinetics, Pharmacodynamics and Safety of Vonoprazan in Adolescents With Symptomatic Gastroesophageal Reflux Disease (NCT NCT05343364)

Last Updated: 2025-04-23

Results Overview

Plasma pharmacokinetic (PK) parameters were estimated using a non-linear mixed effects model and were determined from the concentration-time data for all evaluable participants. Actual sampling times, rather than scheduled or nominal sampling times, were used in all computations using sampling time.

Recruitment status

COMPLETED

Study phase

PHASE1

Target enrollment

24 participants

Primary outcome timeframe

Blood samples were collected predose, once between 0.5 and 2 hours, and once between 2.5 and 4 hours post-dose on Days 7 and 14

Results posted on

2025-04-23

Participant Flow

A total of 24 participants were enrolled into this study in the United States between May 2022 and June 2023.

The total duration of the study was up to 8 weeks. The Screening Period was up to 4 weeks, Treatment Period was 2 weeks, and safety follow-up phone call was 2 weeks after last study drug administration.

Participant milestones

Participant milestones
Measure	Vonoprazan 10 mg QD Participants were randomized to receive vonoprazan 10 mg once daily (QD) from Day 1 to Day 14.	Vonoprazan 20 mg QD Participants were randomized to receive vonoprazan 20 mg QD from Day 1 to Day 14.
Overall Study STARTED	12	12
Overall Study COMPLETED	12	11
Overall Study NOT COMPLETED	0	1

Reasons for withdrawal

Reasons for withdrawal
Measure	Vonoprazan 10 mg QD Participants were randomized to receive vonoprazan 10 mg once daily (QD) from Day 1 to Day 14.	Vonoprazan 20 mg QD Participants were randomized to receive vonoprazan 20 mg QD from Day 1 to Day 14.
Overall Study Miscellaneous	0	1

Baseline Characteristics

A Study to Evaluate the Pharmacokinetics, Pharmacodynamics and Safety of Vonoprazan in Adolescents With Symptomatic Gastroesophageal Reflux Disease

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Vonoprazan 10 mg QD n=12 Participants Participants were randomized to receive vonoprazan 10 mg QD from Day 1 to Day 14.	Vonoprazan 20 mg QD n=12 Participants Participants were randomized to receive vonoprazan 20 mg QD from Day 1 to Day 14.	Total n=24 Participants Total of all reporting groups
Age, Continuous	14.3 years STANDARD_DEVIATION 1.78 • n=5 Participants	15.2 years STANDARD_DEVIATION 1.75 • n=7 Participants	14.8 years STANDARD_DEVIATION 1.78 • n=5 Participants
Sex: Female, Male Female	6 Participants n=5 Participants	7 Participants n=7 Participants	13 Participants n=5 Participants
Sex: Female, Male Male	6 Participants n=5 Participants	5 Participants n=7 Participants	11 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	4 Participants n=5 Participants	2 Participants n=7 Participants	6 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	6 Participants n=5 Participants	10 Participants n=7 Participants	16 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	2 Participants n=5 Participants	0 Participants n=7 Participants	2 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	3 Participants n=5 Participants	5 Participants n=7 Participants	8 Participants n=5 Participants
Race (NIH/OMB) White	9 Participants n=5 Participants	7 Participants n=7 Participants	16 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants

PRIMARY outcome

Timeframe: Blood samples were collected predose, once between 0.5 and 2 hours, and once between 2.5 and 4 hours post-dose on Days 7 and 14

Population: PK set: inclusive of all evaluable participants who had at least one measurable concentration result.

Outcome measures

Outcome measures
Measure	Vonoprazan 10 mg QD n=9 Participants Participants were randomized to receive vonoprazan 10 mg QD from Day 1 to Day 14.	Vonoprazan 20 mg QD n=8 Participants Participants were randomized to receive vonoprazan 20 mg QD from Day 1 to Day 14.
Maximum Observed Drug Concentration at Steady State (Cmax-ss) of Vonoprazan	13.4 ng/mL Interval 6.57 to 25.6	26.7 ng/mL Interval 13.1 to 49.1

PRIMARY outcome

Timeframe: Blood samples were collected predose, once between 0.5 and 2 hours, and once between 2.5 and 4 hours post-dose on Days 7 and 14

Population: PK set: inclusive of all evaluable participants who had at least one measurable concentration result.

PK parameters were estimated using a non-linear mixed effects model and were determined from the concentration-time data for all evaluable participants. Actual sampling times, rather than scheduled or nominal sampling times, were used in all computations using sampling time.

Outcome measures

Outcome measures
Measure	Vonoprazan 10 mg QD n=9 Participants Participants were randomized to receive vonoprazan 10 mg QD from Day 1 to Day 14.	Vonoprazan 20 mg QD n=8 Participants Participants were randomized to receive vonoprazan 20 mg QD from Day 1 to Day 14.
Area Under the Plasma Concentration-time Curve During the Dosing Interval τ (AUCτ) of Vonoprazan	94.6 h*ng/mL Interval 56.0 to 165.0	208 h*ng/mL Interval 95.6 to 381.0

PRIMARY outcome

Timeframe: Blood samples were collected predose, once between 0.5 and 2 hours, and once between 2.5 and 4 hours post-dose on Days 7 and 14

Population: PK set: inclusive of all evaluable participants who had at least one measurable concentration result.

Outcome measures

Outcome measures
Measure	Vonoprazan 10 mg QD n=9 Participants Participants were randomized to receive vonoprazan 10 mg QD from Day 1 to Day 14.	Vonoprazan 20 mg QD n=8 Participants Participants were randomized to receive vonoprazan 20 mg QD from Day 1 to Day 14.
Apparent Oral Clearance (CL/F) of Vonoprazan	124 L/h Interval 60.5 to 179.0	117 L/h Interval 52.5 to 209.0

PRIMARY outcome

Timeframe: Blood samples were collected predose, once between 0.5 and 2 hours, and once between 2.5 and 4 hours post-dose on Days 7 and 14

Population: PK set: inclusive of all evaluable participants who had at least one measurable concentration result.

Outcome measures

Outcome measures
Measure	Vonoprazan 10 mg QD n=9 Participants Participants were randomized to receive vonoprazan 10 mg QD from Day 1 to Day 14.	Vonoprazan 20 mg QD n=8 Participants Participants were randomized to receive vonoprazan 20 mg QD from Day 1 to Day 14.
Apparent Central Volume of Distribution (Vc/F) of Vonoprazan	686 liters Interval 314.0 to 1280.0	704 liters Interval 311.0 to 1110.0

SECONDARY outcome

Timeframe: Up to Day 28

Population: Safety Set: inclusive of all participants who received at least 1 dose of study drug.

AE: any unfavorable and unintended sign, symptom, or disease temporally associated with the use of a drug. Treatment-emergent adverse event (TEAE): any AE that occurred after the first dose of study drug or at baseline that worsens in either intensity or frequency after the first dose of study drug. Serious AE: any AE for which the following occurred: death, was life threatening, hopsitalization or prolongation of hospitalization, persistent or significant disability/incapacity, a congenital anomaly/birth defect, or the AE was deemed an important medical event. Related AE: any AE that follows a reasonable temporal sequence from administration of study drug, or for which possible involvement of the drug cannot be ruled out, although factors other than the study drug may also be responsible. Clinically significant changes from baseline in laboratory test values, (hematology, serum chemistry and urinalysis), electrocardiograms and vital signs were reported as AEs.

Outcome measures

Outcome measures
Measure	Vonoprazan 10 mg QD n=12 Participants Participants were randomized to receive vonoprazan 10 mg QD from Day 1 to Day 14.	Vonoprazan 20 mg QD n=12 Participants Participants were randomized to receive vonoprazan 20 mg QD from Day 1 to Day 14.
Number of Participants Experiencing Adverse Events (AEs) Any TEAEs	4 Participants	1 Participants
Number of Participants Experiencing Adverse Events (AEs) Any Serious TEAEs	0 Participants	0 Participants
Number of Participants Experiencing Adverse Events (AEs) Any Study Drug-related TEAEs	0 Participants	0 Participants
Number of Participants Experiencing Adverse Events (AEs) Any Serious Study Drug-related TEAEs	0 Participants	0 Participants
Number of Participants Experiencing Adverse Events (AEs) Any TEAE Leading to Treatment Discontinuation	0 Participants	0 Participants
Number of Participants Experiencing Adverse Events (AEs) Any TEAE Leading to Study Discontinuation	0 Participants	0 Participants
Number of Participants Experiencing Adverse Events (AEs) Any AEs Leading to Death	0 Participants	0 Participants

Adverse Events

Vonoprazan 10 mg QD

Serious events: 0 serious events

Other events: 4 other events

Deaths: 0 deaths

Vonoprazan 20 mg QD

Serious events: 0 serious events

Other events: 1 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure	Vonoprazan 10 mg QD n=12 participants at risk Participants were randomized to receive vonoprazan 10 mg QD from Day 1 to Day 14.	Vonoprazan 20 mg QD n=12 participants at risk Participants were randomized to receive vonoprazan 20 mg QD from Day 1 to Day 14.
Infections and infestations Cellulitis	8.3% 1/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.	0.00% 0/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.
Infections and infestations Enterocolitis infectious	0.00% 0/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.	8.3% 1/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.
Gastrointestinal disorders Gastrooesophageal reflux disease	8.3% 1/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.	0.00% 0/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.
Musculoskeletal and connective tissue disorders Back pain	8.3% 1/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.	0.00% 0/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.
Nervous system disorders Migraine	8.3% 1/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.	0.00% 0/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.
Psychiatric disorders Anxiety	8.3% 1/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.	0.00% 0/12 • Up to Day 28 Safety Set: inclusive of all participants who received at least 1 dose of study drug.

Additional Information

Phathom Medical Information

Phathom Pharmaceuticals, Inc.

Phone: 1-888-775-7428

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee Principal investigators (PIs) are not permitted to publish the data. Data may be considered for reporting at a scientific meeting or for publication in a scientific journal. In these cases, the sponsor will be responsible for these activities and will work with the PIs to determine how the manuscript is written and edited, the number and order of authors, the publication to which it will be submitted, and any other related issues. The sponsor has final approval authority over all such issues.
Publication restrictions are in place

Restriction type: OTHER