Sickle Cell Clinical Research and Intervention Program

About the study

Despite the important work of previous sickle cell disease (SCD) cohort studies, there remain many understudied areas that require investigation. An important knowledge deficit is the slow but progressive process of chronic end-organ dysfunction. The majority of organ dysfunction becomes apparent in the young adult years, but comprehensive assessment of adults and understanding of predictors of adulthood organ dysfunction are insufficient. Similarly, the role of disease-modifying therapies, such as hydroxyurea, in preventing organ dysfunction later in life is not clear. Extended follow-up of patients through the transition into adulthood is imperative to understand the long-term implications of pediatric sickle cell care.

This observational study will collect data in a systematic fashion at participants’ regular clinic visits (in-person or remote) to answer the objectives described below.

In addition to primary study objectives, SCCRIP participants will be eligible to participate in a sub-study, which will investigate genetically determined responses to Hydroxyurea (HU) via a pharmacokinetic study (PK). This one time study will involve blood collection at timed intervals proceeding a dose of HU. Defining the basis for this inter-individual variability will allow the identification of poor HU responders prior to initiation of therapy and the seeking of alternative treatments which seek to optimize disease treatment by accounting for individual variability in genes, environment, and lifestyle.

Study point of contact

Jane Hankins, MD, MS


6 United States sites

Study type

Observational [Patient Registry]



participation requirements

A diagnosis of sickle cell disease of any genotype.

PK Sub-study Inclusion Criteria:

Participants at St. Jude Children’s Research Hospital who are consented to the parent protocol (SCCRIP, Amendment 6.1 or above).
Participants currently completing a hydroxyurea (HU) regimen, who have achieved maximum tolerated dose and have maintained that dose for a minimum of 90 days prior to enrollment.


participation restrictions

Any medical or social reason, which, in the opinion of the principal investigators would make the participation of the subject ill-advised.

PK Sub-study Exclusion Criteria:

Participants unable to complete the blood draws required for PK sampling.
Inability or unwillingness of research participant or legal guardian/representative to give written informed consent.
Any medical or social reason, which, in the opinion of the principal investigators would make the participation of the subject ill-advised.


  • Peoria, Illinois, United States, Children's Hospital of Illinois at OSF-Saint Francis Medical Center, 61637 [Recruiting]
  • Baton Rouge, Louisiana, United States, Our Lady of the Lake Regional Medical Center, 70808 [Completed]
  • Charlotte, North Carolina, United States, Novant Health Hemby Children's Hospital, 28204 [Recruiting]
  • Memphis, Tennessee, United States, Regional One Health, Diggs-Kraus Sickle Cell Center, 38103 [Not yet recruiting]
  • Memphis, Tennessee, United States, Methodist Adult Comprehensive Sickle Cell Center, 38104 [Recruiting]
  • Memphis, Tennessee, United States, St. Jude Children's Research Hospital, 38105 [Recruiting]
Last updated 2022-11-15