Trial Outcomes & Findings for Genetic Testing to Understand and Address Renal Disease Disparities Across the United States Pharmacogenetic Substudy (NCT NCT06748040)

NCT ID: NCT06748040

Last Updated: 2025-06-17

Results Overview

• Recruitment status: COMPLETED
• Study phase: NA
• Target enrollment: 1874 participants
• Primary outcome timeframe: Baseline to 3 month study visit
• Results posted on: 2025-06-17

Participant Flow

Participants were recruited by providers who care for participants with hypertension (including, for example, general internists, primary care providers, and nephrologists).

Among the 6754 participants randomized into the GUARDD-US main trial, 1874 participants were further randomized into the GUARDD-US PGx substudy. These participants were assigned to the 'Immediate Return of Results' treatment group in the main trial, were from PGx-substudy participating sites and had an APOL1 negative phenotype. For this study, APOL1 negative refers to participants without 2 high risk alleles at the APOL1 locus also termed as without APOL1-HR.

Participant milestones

Measure	Immediate Return of Results Immediate return of pharmacogenetic (PGx) results to substudy (APOL1 negative) participant.	Delayed Return of Results Delayed return of pharmacogenetic (PGx) results to substudy (APOL1 negative) participant until after the completion of the 6 month final study visit.
Overall Study STARTED	953	921
Overall Study COMPLETED	813	780
Overall Study NOT COMPLETED	140	141

Reasons for withdrawal

Measure	Immediate Return of Results Immediate return of pharmacogenetic (PGx) results to substudy (APOL1 negative) participant.	Delayed Return of Results Delayed return of pharmacogenetic (PGx) results to substudy (APOL1 negative) participant until after the completion of the 6 month final study visit.
Overall Study Death	3	4
Overall Study Lost to Follow-up	134	132
Overall Study Withdrawal by Subject	3	5

Baseline Characteristics

Genetic Testing to Understand and Address Renal Disease Disparities Across the United States Pharmacogenetic Substudy

Baseline characteristics by cohort

Measure	Immediate Return of Results n=953 Participants Immediate return of pharmacogenetic (PGx) results to substudy (APOL1 negative/without APOL1-HR) participant.	Delayed Return of Results n=921 Participants Delayed return of pharmacogenetic (PGx) results to substudy (APOL1 negative/without APOL1-HR) participant until after the completion of the 6 month final study visit.	Total n=1874 Participants Total of all reporting groups
Age, Continuous	55.3 years STANDARD_DEVIATION 10.4 • n=5 Participants	54.7 years STANDARD_DEVIATION 11.0 • n=7 Participants	55.0 years STANDARD_DEVIATION 10.7 • n=5 Participants
Sex: Female, Male Female	610 Participants n=5 Participants	590 Participants n=7 Participants	1200 Participants n=5 Participants
Sex: Female, Male Male	343 Participants n=5 Participants	331 Participants n=7 Participants	674 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	32 Participants n=5 Participants	35 Participants n=7 Participants	67 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	917 Participants n=5 Participants	879 Participants n=7 Participants	1796 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	4 Participants n=5 Participants	7 Participants n=7 Participants	11 Participants n=5 Participants
Race/Ethnicity, Customized Race · American Indian or Alaska Native	2 Participants n=5 Participants	0 Participants n=7 Participants	2 Participants n=5 Participants
Race/Ethnicity, Customized Race · Asian	1 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants
Race/Ethnicity, Customized Race · Native Hawaiian or Other Pacific Islander	2 Participants n=5 Participants	0 Participants n=7 Participants	2 Participants n=5 Participants
Race/Ethnicity, Customized Race · Black or African American	852 Participants n=5 Participants	828 Participants n=7 Participants	1680 Participants n=5 Participants
Race/Ethnicity, Customized Race · White	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race/Ethnicity, Customized Race · North African/Mediterranean	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants
Race/Ethnicity, Customized Race · More than one race	65 Participants n=5 Participants	60 Participants n=7 Participants	125 Participants n=5 Participants
Race/Ethnicity, Customized Race · Unknown or Not Reported	31 Participants n=5 Participants	32 Participants n=7 Participants	63 Participants n=5 Participants
Region of Enrollment United States	953 Participants n=5 Participants	921 Participants n=7 Participants	1874 Participants n=5 Participants

PRIMARY outcome

Timeframe: Baseline to 3 month study visit

Population: Intent To Treat (ITT) population for PGx substudy.

Outcome measures

Measure	Immediate Return of Results n=877 Participants Immediate return of pharmacogenetic (PGx) results to substudy (APOL1 negative/without APOL1-HR) participant.	Delayed Return of Results n=830 Participants Delayed return of pharmacogenetic (PGx) results to substudy (APOL1 negative/without APOL1-HR) participant until after the completion of the 6 month final study visit.
Change in Systolic Blood Pressure From Baseline to 3 Months for APOL1 Negative Participants	-3.7 mmHg Standard Deviation 19.0	-3.1 mmHg Standard Deviation 19.0

Adverse Events

Immediate Return of Results

Serious events: 0 serious events

Other events: 0 other events

Deaths: 3 deaths

Delayed Return of Results

Serious events: 0 serious events

Other events: 0 other events

Deaths: 4 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Hrishikesh Chakraborty, PhD

Duke University

Phone: 919-668-1238

Email: hrishikesh.chakraborty@duke.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place