Recruiting

Observational Study

Sponsor:

National Heart, Lung, and Blood Institute (NHLBI)

Code:

NCT03685721

Conditions

Sickle Cell

PKLR Variants

Adenosine Triphosphate Activities

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

Study Details

Brief summary:

Background:

Some people with the same disorder on a genetic level have more complications than others. Researchers want to look for a link between the PKLR gene and sickle cell disease (SCD) symptoms. The PKLR gene helps create a protein, called pyruvate kinase that is essential in normal functioning of the red blood cell. Differences in the PKLR gene, called genetic variants, may cause some changes in the pyruvate kinase protein and other proteins, that can affect functioning of the red blood cell adding to the effect of SCD. Researchers can study these differences by looking at DNA (the material that determines inherited characteristics).

Objective:

To study how the PKLR gene affects sickle cell disease.

Eligibility:

Adults ages 18-80 of African descent. They may have sickle cell disease or not. They must not have had a transfusion recently or have a known deficiency of pyruvate kinase. They cannot be pregnant.

Design:

Participants will be screened with questions.

Participants will have blood drawn by needle in an arm vein. The blood will be genetically tested. Not much is known about how genes affect SCD, so the test results will not be shared with participants or their doctors.

...

Conditions

Sickle Cell

PKLR Variants

Adenosine Triphosphate Activities

Study ID

NCT03685721

Start date

Oct 11, 2018

Status verified date

Aug 13, 2026

Completion date

Jul 1, 2027

Anticipated

Primary completion date

Jul 1, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

  • INCLUSUION CRITERIA:
  • Between 18 and 80 years of age
  • African or of African descent
  • Capacity to consent is required

EXCLUSION CRITERIA:

  • Self-reported history of blood transfusion within the last 8 weeks
  • Known to have pyruvate kinase deficiency and be on AG348
  • All volunteers will undergo the consent process under this protocol to allow for eligibility assessment. Once they have been consented to participate, they will undergo procedures per Protocol.

Study Design

Enrollment

800 participants

Anticipated

Interventions and Outcome Measures

Arms

HbAS

HbAS genotype, of African American descent;Between 18 and 80 years of age

Healthy control

African American descent;Between 18 and 80 years of age

SCD

HbSS, HbSC, HbSbeta-thal has sickle cell disease and is of African American descent;Between 18 and 80 years of age

Primary outcome measure

  • Genotype the 4 PKLR intron-2 variants [ Time Frame: Upon enrollment of each subject ]
  • Analysis of PK-R transcriptome in red blood cells [ Time Frame: Interim analysis performed for each group N=125 ]
  • Correlation of 2,3-DPG, ATP and pyruvate kinase activities with PKLR intron-2 variants [ Time Frame: Interim analysis performed for each group N=125 ]

Central Contacts and Locations

Central contacts

Locations

National Institutes of Health Clinical Center

Recruiting

Bethesda, Maryland, United States, 20892

Contacts

For more information at the NIH Clinical Center contact Office of Patient Recruitment (OPR)

800-411-1222prpl@cc.nih.gov

More Information

Sponsor

National Heart, Lung, and Blood Institute (NHLBI)

Last update posted

Aug 17, 2026

Last verified

Aug 13, 2026

Keywords

  • ATP
  • Trait
  • GDP
  • Genetics
  • Natural History

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by National Heart, Lung, and Blood Institute (NHLBI) on 2026-08-17.