A Study to Learn About Sickle Cell Disease In Adult Patients

A LOW-INTERVENTIONAL LONGITUDINAL STUDY OF AN ELECTRONIC SICKLE CELL DISEASE PATIENT REPORTED OUTCOMES IN ADULT PARTICIPANTS AGED ≥18 YEARS OF AGE ON AND OFF HYDROXYUREA

The purpose of this clinical trial is to evaluate the performance of the sickle cell disease (SCD) electronic diary in people with SCD who are on treatment that will change SCD and those not on such a treatment.

SCD is a type of condition when there are fewer red blood cells to carry oxygen around the body.

This disease can be passed on from parent to child and may cause pain, infections and damage to organs.

This study is seeking participants who:

• are confirmed with SCD
• are on a stable regimen of disease changing treatment or have not received any disease changing treatment before the start of the study and do not plan any changes in their treatment during the 6-month study observation period For 6 months, participants will be asked to complete a daily electronic diary to report on their experience in the past 24 hours with sickle cell pain crisis (if they got any treatment and what medications they took), worst pain, worst tiredness, and their ability to perform usual physical activities. We will compare the experiences of people who are taking SCD-modifying therapy to those that are not taking a SCD-modifying therapy.

Study Overview

• Status: Completed
• Conditions: Sickle Cell Disease
• Intervention / Treatment: Other: Electronic Diary

• Study Type: Observational
• Enrollment (Actual): 98

Contacts and Locations

Study Locations

• United States
  • Florida
    • Hollywood, Florida, United States, 33024
      • Foundation for Sickle Cell Disease Research
  • Maryland
    • Upper Marlboro, Maryland, United States, 20774
      • Mid-Atlantic Permanente Medical Group Largo Medical Center
  • Massachusetts
    • Waltham, Massachusetts, United States, 02451
      • Sanguine Biosciences, Inc.
  • New York
    • New Hyde Park, New York, United States, 11040
      • Cohen Children's Medical Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Participants with a confirmed diagnosis of stable Sickle Cell Disease (SCD) (hemoglobin S inherited from both parents [HbS/S] or hemoglobin S inherited from one parent and hemoglobin beta thalassemia inherited from the other parent [HbS/beta-zero-thalassemia] genotype) who are either not on disease modifying treatment or on a stable dose of a SCD disease modifying treatment regimen.

Description

Inclusion Criteria (All Groups):

- Confirmed diagnosis of stable SCD (HbS/S or HbS/beta-zero-thalassemia).

Additional Inclusion Criteria (No Disease Modifying Treatment Control Group):

• Have experienced ≥1 episode(s) of medical utilization (MU) VOC within 12 months prior to Screening.
• Data available for number of MU VOC(s) during the 12-month interval prior to Screening and a value for %fetal hemoglobin (HbF) collected subsequent to 1 year of age in the absence of recent transfusion.

Additional Inclusion Criteria (SCD Disease Modifying Treatment Group):

• Have experienced ≥1 episode(s) of MU VOC within 12 months prior to initiation of HU and/or crizanlizumab (whichever was initiated earlier).

• Must be on a stable dose of their SCD treatment regimen ≥8 weeks prior to Day 1 with the intent of remaining on the same dose throughout the study, unless adjustments are medically necessary due to bone marrow suppression, in accordance with published guidelines and/or product specific guidance (eg, package label). Accepted SCD disease modifying treatment regimens include:

  • HU alone and/or in combination with crizanlizumab, L-glutamine and/or voxelotor; or
  • Crizanlizumab alone and/or in combination with HU, L-glutamine and/or voxelotor.
• Data available for number of MU VOC(s) during the 12-month interval prior to initiation of any SCD disease modifying treatment, as described above, and a value for %HbF collected subsequent to 1 year of age, prior to initiation of any HU treatment, and in the absence of recent transfusion.

Exclusion Criteria (All Groups):

• Evidence or history of ongoing (condition or sequelae) clinically significant hematological (non-SCD), renal, endocrine, pulmonary, gastrointestinal, cardiovascular (including overt stroke but excluding silent cerebral infarct), hepatic (excluding cholelithiasis), psychiatric or neurological disease as assessed from medical records.
• Marked ongoing bone marrow suppression as evidenced by any of the following as per medical record: severe anemia, absolute neutrophil count (ANC) <1000 mm3 white blood cell (WBC), thrombocytopenia (platelet count <100,000 mm3) within ≤8 weeks prior to Day 1 enrollment.
• History of hematopoietic stem cell transplant or treatment with gene therapy as assessed from medical records.
• History of simple transfusion within ≤4 weeks prior to Day 1 enrollment as assessed from medical records or participant self-report.
• History of chronic transfusion/exchange transfusion within ≤12 weeks prior to Day 1 enrollment as assessed from medical records or participant self-report and/or plan to initiate such treatment during the 6-month observation period.

Additional Exclusion Criteria (No Disease Modifying Treatment Control Group):

• Participant received HU and/or crizanlizumab at any time within ≤18 months of Day 1 enrollment and treatment(s) was discontinued due to lack of efficacy (no reduction in the frequency of VOCs, documented or perceived) and/or plan to initiate said treatment(s) during the 6-month observation period.
• Participant received voxelotor or L-glutamine within ≤4 weeks of Day 1 enrollment and/or plan to initiate said treatment(s) during the 6-month observation period.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Control Group; SCD participants not on disease modifying treatment.	Other: Electronic Diary; Participants will be asked to complete a daily electronic patient reported outcome diary entry to report on their experience in the past 24 hours.; Other Names: SCD electronic patient reported outcome (ePRO)
SCD Disease Modifying Treatment Group; SCD participants on a stable dose of a SCD disease modifying treatment regimen.	Other: Electronic Diary; Participants will be asked to complete a daily electronic patient reported outcome diary entry to report on their experience in the past 24 hours.; Other Names: SCD electronic patient reported outcome (ePRO)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Physician-reported Medical Utilization (MU) Vaso-occlusive Crisis (VOC) Rate	Physician-reported MU VOC: defined as an acute episode of pain with no other cause other than a VOC event that required a medical facility visit or contact with a health care professional and treatment with oral or parenteral narcotics, or non-steroidal anti-inflammatory drugs. Acute chest syndrome, hepatic sequestration, splenic sequestration, and priapism (requiring a visit to a medical facility) were also considered MU VOC. Contact with healthcare professional included: called healthcare provider (or telemedicine visit) and received treatment, went to clinic and received treatment, went to emergency department and received treatment, admitted to the hospital and received treatment. VOC rate was derived as annualized rate. Annualized MU VOC rate = (Number of MU VOC events * 365)/ (number of days in the observation period).	Baseline up to Day 180
VOC Day Rate	A VOC was a complication of SCD characterized by vaso-occlusion presenting as recurrent pain episodes. VOC day was a self-report by the participant of experiencing a VOC during the past 24 hours. This was assessed through a dichotomous (Yes/No) item on the SCD ePRO system, "Did you have a pain crisis in the past 24 hours?" A response of "Yes" indicated a VOC day. VOC day rate was derived as annualized rate. VOC day rate = (Number of VOC days * 365)/ (number of days in the observation period).	Baseline up to Day 180
Patient-reported VOC Event Rate	A VOC was a complication of SCD characterized by vaso-occlusion presenting as recurrent pain episodes. Patient reported VOC Event is used to define a sequence of VOC days that could also include single intervening days with no pain crisis. The subsequent occurrence of two consecutive days with no pain crisis operationally defines the end of the respective VOC event. Rate were derived as annualized rate. Annualized VOC event rate = (Number of VOC events * 365)/ (number of days in the observation period).	Baseline up to Day 180
Sickle Cell Disease (SCD) Electronic Patient Reported Outcome (ePRO) Daily Worst Pain Scores by VOC Status	A VOC was a complication of SCD characterized by vaso-occlusion presenting as recurrent pain episodes. VOC day was defined as the day on which a SCD participant self-reports sickle pain crisis that was recorded in the SCD ePRO. A non-VOC day was defined as the day on which a SCD participant does not self-reports sickle pain crisis. Participants rated their pain by selecting the one number that best described their pain at its worst in the past 24 hours from 0-10, where 0= no pain and 10= as bad as you can imagine. Higher scores indicated worse pain. Data in this outcome measure was presented separately for VOC state and non-VOC state.	Baseline up to Day 180
Sickle Cell Disease Electronic Patient Reported Outcome Daily Worst Tiredness Scores by VOC Status	A VOC was a complication of SCD characterized by vaso-occlusion presenting as recurrent pain episodes. VOC day was defined as the day on which a SCD participant self-reports sickle pain crisis that was recorded in the SCD ePRO. A non-VOC day was defined as the day on which a SCD participant does not self-reports sickle pain crisis. Participants rated their tiredness by selecting the one number that best described their tiredness at its worst in the past 24 hours from 0-10, where 0= no tiredness and 10= as bad as you can imagine. Higher scores indicated worse tiredness. Data in this outcome measure was presented separately for VOC state and non-VOC state.	Baseline up to Day 180
Sickle Cell Disease Electronic Patient Reported Outcome Daily Rating for Ability to Perform Usual Physical Activity (UPA) by VOC Status	A VOC was a complication of SCD characterized by vaso-occlusion presenting as recurrent pain episodes. VOC day was defined as the day on which a SCD participant self-reports sickle pain crisis that was recorded in the SCD ePRO. A non-VOC day was defined as the day on which a SCD participant does not self-reports sickle pain crisis. A measure of participant's ability to perform their UPA (e.g. walking, climbing stairs, or household chores) during a VOC event was assessed on SCD ePRO recorded by participants using a scale ranging from 1-4 scale, where 1= able to perform with no difficulty and 4= unable to perform usual physical activities, where higher score indicated worse status. Data in this outcome measure was presented separately for VOC state and non-VOC state.	Baseline up to Day 180

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent Change in Physician-reported MU VOC Rate Per Unit of Change in VOC Day Rate	MU VOC: acute episode of pain with no other cause other than VOC event that required medical facility visit/contact with health care professional and treatment with oral/parenteral narcotics/NSAIDs. Acute chest syndrome,hepatic/splenic sequestration, priapism also considered MU VOC. MU VOC derived as annualized rate by:(Number of MU VOC events*365)/(number of days in observation period). VOC day rate: VOC day was self-report by participant experiencing VOC during past 24 hours. It was assessed by dichotomous (Yes/No) item on SCD ePRO system, "Did you have pain crisis in past 24 hours?" Response "Yes" indicated VOC day. VOC day rate derived as annualized rate by: (Number of VOC days*365)/(number of days in observation period). Parameter of interest was % change of MU VOC rate per unit of change in VOC Day rate. It was estimated via Negative Binomial model to evaluate association between physician-reported MU VOC rate and SCD ePRO VOC Day rate and was reported with corresponding 95% CI.	Baseline up to Day 180
Percent Change in Physician-reported MU VOC Rate Per Unit of Change in Patient-reported VOC Event Rate	MU VOC: acute episode of pain with no other cause other than VOC event that required medical facility visit/contact with health care professional and treatment with oral/parenteral narcotics/NSAIDs. Acute chest syndrome, hepatic/splenic sequestration, priapism also considered MU VOC. MU VOC derived as annualized rate by:(Number of MU VOC events*365)/(number of days in observation period). VOC Event rate: Patient-reported VOC Event is used to define a sequence of VOC days. The subsequent occurrence of two consecutive days with no pain crisis operationally defines the end of the respective VOC event. Rate were derived as annualized rate by: (Number of VOC events * 365)/ (number of days in the observation period). Parameter of interest was % change of MU VOC rate per unit of change in VOC Event rate. It was estimated via Negative Binomial model to evaluate association between physician-reported MU VOC rate and SCD ePRO VOC Event rate and was reported with corresponding 95% CI.	Baseline up to Day 180

Collaborators and Investigators

• Sponsor: Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

Helpful Links

• To obtain contact information for a study center near you, click here.

Study record dates

Study Major Dates

• Study Start (Actual): February 10, 2022
• Primary Completion (Actual): June 24, 2024
• Study Completion (Actual): June 24, 2024

Study Registration Dates

• First Submitted: May 18, 2022
• First Submitted That Met QC Criteria: June 2, 2022
• First Posted (Actual): June 7, 2022

Study Record Updates

• Last Update Posted (Actual): June 10, 2026
• Last Update Submitted That Met QC Criteria: May 14, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Vaso-occlusive crisis (VOC); Hemoglobin S (HbS)
• Additional Relevant MeSH Terms: Genetic Diseases, Inborn; Hematologic Diseases; Anemia, Hemolytic, Congenital; Anemia, Hemolytic; Anemia; Hemoglobinopathies; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Hemic and Lymphatic Diseases; Anemia, Sickle Cell; Sickle Cell Trait; Vaso-Occlusive Crises
• Other Study ID Numbers: C4071008; NCT05407805 (Registry Identifier: ClinicalTrials.gov)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.