Sickle Cell DiseasePhase 1NCT07431398
Single-dose Pharmacokinetics of Pociredir in Participants With Sickle Cell Disease
A Phase 1 study testing Pociredir in people with Sickle Cell Disease, run by Fulcrum Therapeutics at 6 sites in United States.
Trial summary
This clinical trial is a study to evaluate the pharmacokinetics of the tablet formulation Pociredir in fasted and fed state participants with Sickle Cell Disease (SCD). Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Sickle Cell Disease
- What is being tested?
- Pociredir
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 13 participants
- Where
- 6 sitesUnited States
- Study dates
- 13 Dec 2025to 1 Jun 2026
- Phase
- Phase 1
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Documented SCD at the time of screening, as confirmed through review of medical records or high-performance liquid chromatography (HPLC)/electrophoresis.
- Participant, who if female and of childbearing potential, agrees to use 2 effective methods of contraception, one which must be highly effective, or practice abstinence starting at the time of the ICF signing to 90 days after the last dose of study drug, and, who if male, agrees to use condoms or practice abstinence from the time of ICF signing to 90 days after the last dose of study drug.
- Total Hb ≥ 5.5 grams/deciliter (g/dL) and ≤ 12 g/dL (males) or ≤ 10.6 g/dL (females) at screening
- Participant must meet all of the following laboratory values at screening:
- Absolute neutrophil count ≥ 1.5 × 10^9/L (cells/liter)
- Platelets ≥ 80 × 10^9/L
- Absolute reticulocyte count > 100 × 10^9/L
- Participants who meet all other inclusion and exclusion criteria for this study, and per Investigator's recommendation may continue crizanlizumab, and/or L-glutamine, must be on a stable dose for at least 6 months
Who cannot join
- Participant has had any of the following in the 14 days prior to dosing: major surgery, serious illness, infection (clinically significant bacterial, fungal, parasitic or viral infection which requires therapy), fever not resolved within 3 days and requiring treatment, or sickle cell complication requiring care from a medical provider in a hospital or emergency care setting.
- Participant has a serious medical condition other than SCD that, in the opinion of the Investigator, would preclude them from participating in the study, or which is unresolved or requiring ongoing treatment.
- Elective surgery planned for the time period of the study.
- Use of any medications that induce or inhibit cytochrome P450 (CYP) 3A4, inhibit P-glycoprotein, breast cancer resistance protein, or multidrug and toxin extrusion protein 2-K, or are substrates of CYP2B6 within 14 days prior to first dose of study drug or anticipated need for any of these medications during the study.
- Participation in any other study with an investigational agent within the past 30 days or 5 half-lives, whichever is longer, prior to the first dose of study drug.
- For Fed Cohort Only: Participant has special dietary restrictions or inability to consume standard meals as required in the study.
- Note: Other protocol specified criteria may apply.
Trial locations and contacts
6 sites in 1 country.
6 sites in 1 country
United States6 sites
University of Texas Health Science Center Houston
Houston, Texas, 77030
Advanced Pharma - Miami
Miami, Florida, 33147
Neuro-Behavioral Clinical Research
North Canton, Ohio, 44720
Omega Research Group
Orlando, Florida, 32808
Sonar Clinical Research
Riverdale, Georgia, 30274
Worldwide Clinical Trials
San Antonio, Texas, 78217
About this study
Official title: A Phase 1, Open-Label Study to Assess Pharmacokinetics After Single Doses of Pociredir in Participants With Sickle Cell Disease
This clinical trial is a study to evaluate the pharmacokinetics of the tablet formulation Pociredir in fasted and fed state participants with Sickle Cell Disease (SCD).
Read the detailed description
The study is designed to assess the pharmacokinetics of the tablet formulation of pociredir under fasted conditions in up to approximately 12 study participants with SCD (Fasted Cohort). An additional cohort of up to approximately 12 study participants with SCD may be enrolled to evaluate the potential effect of food on the PK of the tablet formulation (Fed Cohort). The fasted cohort will be conducted first.
The study will include screening period: Day -28 to Day -2; In-patient confinement period: Days -1 to 3; check-in on day -1; single dose of pociredir on day 1; discharge on Day 3; outpatient visit: Day 4; end of study (EOS) visit: Days 8-11
Eligible participants who meet all inclusion and none of the exclusion criteria will be admitted to the clinical site on Day -1, the day before dosing. Participants may be discharged on Day 3 following completion of 48-hour PK sampling or may remain in-clinic through Day 4 if needed. Fasted Cohort: Participants will fast for at least 10 hours prior to dosing and remain fasted for 4 hours post-dose. Water intake will be restricted for 1 hour before and after administration of the investigational medicinal product (IMP). Fed Cohort (if conducted): Participants will fast for at least 10 hours prior to breakfast and will receive a standard high-fat breakfast starting 30 minutes before dosing.
Pharmacokinetic samples will be collected up to 72 hours post-dose. Participants are required to remain in-clinic for the first 48 hours post-dose and may return to the site for subsequent Outpatient and EOS visits.
- Conditions
- Sickle Cell Disease
- Being tested
- Pociredir
- Keywords
- Sickle Cell Disease, Hemoglobin subunit beta, fetal hemoglobin, Pharmacokinetics, Pociredir, FTX-6058, Tablet Pharmacokinetics Study, Anemia, Sickle Cell, Hematologic diseases, Small Molecule
- Medical subject headings
- Anemia, Sickle Cell, beta-Thalassemia, Hematologic Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PociredirDrug
Pociredir tablet formulation
| Study group | Role | What they receive |
|---|---|---|
| Fasted Cohort | Experimental | Pociredir single dose tablet formulation under fasted conditions. Receives: Drug: Pociredir |
| Fed Cohort | Experimental | Pociredir single dose tablet formulation under fed conditions (after a high-fat breakfast). Receives: Drug: Pociredir |
What is being measured
The primary outcome is the main question the study is designed to answer.
Plasma concentration of pociredir under fasted and fed conditions
Measured: Day 1 through Day 4
Maximum plasma concentration (Cmax) of pociredir under fasted and fed conditions
Measured: Day 1 through Day 4
Area under the plasma concentration-time curve from time 0 to 24 hours (AUC(0-24)) of pociredir under fasted and fed conditions
Measured: Day 1 through Day 4
Area under the plasma concentration-time curve from time 0 to the last measurable concentration (AUC(0-tlast)) of pociredir under fasted and fed conditions
Measured: Day 1 through Day 4
Area under the plasma concentration-time curve from time 0, extrapolated to infinity (AUC(0-inf)), of pociredir under fasted and fed conditions
Measured: Day 1 through Day 4
Time to maximum plasma concentration (Tmax) of pociredir under fasted and fed conditions
Measured: Day 1 through Day 4
Terminal disposition rate constant (λz) of pociredir under fasted and fed conditions
Measured: Day 1 through Day 4
Terminal half-life (t1/2) of pociredir under fasted and fed conditions
Measured: Day 1 through Day 4
Apparent volume of distribution during the terminal phase (Vz/F) of pociredir under fasted and fed conditions
Measured: Day 1 through Day 4
Apparent clearance (CL/F) of pociredir under fasted and fed conditions
Measured: Day 1 through Day 4
Secondary outcomes (13)
Number of participants with treatment emergent adverse events (TEAEs) under fasted and fed conditions
Measured: Up to Day 11
Number of participants with clinically significant changes in safety assessments under fasted and fed conditions
Measured: Up to Day 11
Number of participants with clinically significant findings in clinical laboratory evaluations, vital signs, electrocardiogram (ECGs) and physical examination
Measured: Up to Day 11
Plasma concentration of pociredir under fasted and fed conditions compared to healthy participants
Measured: Day 1 through Day 4
Cmax of pociredir under fasted and fed conditions compared to healthy participants
Measured: Day 1 through Day 4
AUC(0-24) of pociredir under fasted and fed conditions compared to healthy participants
Measured: Day 1 through Day 4
AUC(0-tlast) of pociredir under fasted and fed conditions compared to healthy participants
Measured: Day 1 through Day 4
AUC(0-inf), under fasted and fed conditions compared to healthy participants
Measured: Day 1 through Day 4
Tmax of pociredir under fasted and fed conditions compared to healthy participants
Measured: Day 1 through Day 4
λz of pociredir under fasted and fed conditions compared to healthy participants
Measured: Day 1 through Day 4
t1/2 of pociredir under fasted and fed conditions compared to healthy participants
Measured: Day 1 through Day 4
Vz/F of pociredir under fasted and fed conditions compared to healthy participants
Measured: Day 1 through Day 4
CL/F of pociredir under fasted and fed conditions compared to healthy participants
Measured: Day 1 through Day 4
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Feb 2026
- Study start13 Dec 2025
- Primary completion1 Jun 2026
- Study completion1 Jun 2026
Why it stopped: Sponsor decision
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Sickle Cell DiseaseStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Sequential
- Masking
- None (open label)
- Enrolment
- 13 participants (actual)
Sponsor and investigators
- Lead sponsor
- Fulcrum Therapeutics
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07431398
- Sponsor's protocol ID
- 6058-CLP-104
- Status last verified
- Jun 2026
- First submitted
- 18 Feb 2026
- Last updated
- 18 Jun 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 18 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 1, Open-Label Study to Assess Pharmacokinetics After Single Doses of Pociredir in Participants With Sickle Cell Disease
- ClinicalTrials.gov ID
- NCT07431398
- Acronym / sponsor ID
- 6058-CLP-104
- Conditions
- Sickle Cell Disease
- Keywords
- Sickle Cell Disease, Hemoglobin subunit beta, fetal hemoglobin, Pharmacokinetics, Pociredir, FTX-6058, Tablet Pharmacokinetics Study, Anemia, Sickle Cell
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: Sponsor decision
- Enrolment
- 13 participants (actual)
- Lead sponsor
- Fulcrum TherapeuticsIndustry (pharma, biotech, devices)
- Study start
- 13 Dec 2025 (actual)
- Primary completion
- 1 Jun 2026 (actual)
- Study completion
- 1 Jun 2026 (actual)
- First posted
- 24 Feb 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This clinical trial is a study to evaluate the pharmacokinetics of the tablet formulation Pociredir in fasted and fed state participants with Sickle Cell Disease (SCD).
Detailed description
The study is designed to assess the pharmacokinetics of the tablet formulation of pociredir under fasted conditions in up to approximately 12 study participants with SCD (Fasted Cohort). An additional cohort of up to approximately 12 study participants with SCD may be enrolled to evaluate the potential effect of food on the PK of the tablet formulation (Fed Cohort). The fasted cohort will be conducted first.
The study will include screening period: Day -28 to Day -2; In-patient confinement period: Days -1 to 3; check-in on day -1; single dose of pociredir on day 1; discharge on Day 3; outpatient visit: Day 4; end of study (EOS) visit: Days 8-11
Eligible participants who meet all inclusion and none of the exclusion criteria will be admitted to the clinical site on Day -1, the day before dosing. Participants may be discharged on Day 3 following completion of 48-hour PK sampling or may remain in-clinic through Day 4 if needed. Fasted Cohort: Participants will fast for at least 10 hours prior to dosing and remain fasted for 4 hours post-dose. Water intake will be restricted for 1 hour before and after administration of the investigational medicinal product (IMP). Fed Cohort (if conducted): Participants will fast for at least 10 hours prior to breakfast and will receive a standard high-fat breakfast starting 30 minutes before dosing.
Pharmacokinetic samples will be collected up to 72 hours post-dose. Participants are required to remain in-clinic for the first 48 hours post-dose and may return to the site for subsequent Outpatient and EOS visits.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Sequential
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Fasted Cohort | Experimental | Drug: PociredirPociredir single dose tablet formulation under fasted conditions. |
| Fed Cohort | Experimental | Drug: PociredirPociredir single dose tablet formulation under fed conditions (after a high-fat breakfast). |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (8 listed)
- Documented SCD at the time of screening, as confirmed through review of medical records or high-performance liquid chromatography (HPLC)/electrophoresis.
- Participant, who if female and of childbearing potential, agrees to use 2 effective methods of contraception, one which must be highly effective, or practice abstinence starting at the time of the ICF signing to 90 days after the last dose of study drug, and, who if male, agrees to use condoms or practice abstinence from the time of ICF signing to 90 days after the last dose of study drug.
- Total Hb ≥ 5.5 grams/deciliter (g/dL) and ≤ 12 g/dL (males) or ≤ 10.6 g/dL (females) at screening
- Participant must meet all of the following laboratory values at screening:
- Participants who meet all other inclusion and exclusion criteria for this study, and per Investigator's recommendation may continue crizanlizumab, and/or L-glutamine, must be on a stable dose for at least 6 months
Key exclusion criteria (7 listed)
- Participant has had any of the following in the 14 days prior to dosing: major surgery, serious illness, infection (clinically significant bacterial, fungal, parasitic or viral infection which requires therapy), fever not resolved within 3 days and requiring treatment, or sickle cell complication requiring care from a medical provider in a hospital or emergency care setting.
- Participant has a serious medical condition other than SCD that, in the opinion of the Investigator, would preclude them from participating in the study, or which is unresolved or requiring ongoing treatment.
- Elective surgery planned for the time period of the study.
- Use of any medications that induce or inhibit cytochrome P450 (CYP) 3A4, inhibit P-glycoprotein, breast cancer resistance protein, or multidrug and toxin extrusion protein 2-K, or are substrates of CYP2B6 within 14 days prior to first dose of study drug or anticipated need for any of these medications during the study.
- Participation in any other study with an investigational agent within the past 30 days or 5 half-lives, whichever is longer, prior to the first dose of study drug.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| PociredirPociredir tablet formulation | Drug | Fasted Cohort, Fed Cohort |
Primary outcome
Plasma concentration of pociredir under fasted and fed conditions
Time frame: Day 1 through Day 4
Maximum plasma concentration (Cmax) of pociredir under fasted and fed conditions
Time frame: Day 1 through Day 4
Area under the plasma concentration-time curve from time 0 to 24 hours (AUC(0-24)) of pociredir under fasted and fed conditions
Time frame: Day 1 through Day 4
Area under the plasma concentration-time curve from time 0 to the last measurable concentration (AUC(0-tlast)) of pociredir under fasted and fed conditions
Time frame: Day 1 through Day 4
Area under the plasma concentration-time curve from time 0, extrapolated to infinity (AUC(0-inf)), of pociredir under fasted and fed conditions
Time frame: Day 1 through Day 4
Time to maximum plasma concentration (Tmax) of pociredir under fasted and fed conditions
Time frame: Day 1 through Day 4
Terminal disposition rate constant (λz) of pociredir under fasted and fed conditions
Time frame: Day 1 through Day 4
Terminal half-life (t1/2) of pociredir under fasted and fed conditions
Time frame: Day 1 through Day 4
Apparent volume of distribution during the terminal phase (Vz/F) of pociredir under fasted and fed conditions
Time frame: Day 1 through Day 4
Apparent clearance (CL/F) of pociredir under fasted and fed conditions
Time frame: Day 1 through Day 4
13 secondary outcomes
Number of participants with treatment emergent adverse events (TEAEs) under fasted and fed conditions
Time frame: Up to Day 11
Number of participants with clinically significant changes in safety assessments under fasted and fed conditions
Time frame: Up to Day 11
Number of participants with clinically significant findings in clinical laboratory evaluations, vital signs, electrocardiogram (ECGs) and physical examination
Time frame: Up to Day 11
Plasma concentration of pociredir under fasted and fed conditions compared to healthy participants
Time frame: Day 1 through Day 4
Cmax of pociredir under fasted and fed conditions compared to healthy participants
Time frame: Day 1 through Day 4
AUC(0-24) of pociredir under fasted and fed conditions compared to healthy participants
Time frame: Day 1 through Day 4
AUC(0-tlast) of pociredir under fasted and fed conditions compared to healthy participants
Time frame: Day 1 through Day 4
AUC(0-inf), under fasted and fed conditions compared to healthy participants
Time frame: Day 1 through Day 4
Tmax of pociredir under fasted and fed conditions compared to healthy participants
Time frame: Day 1 through Day 4
λz of pociredir under fasted and fed conditions compared to healthy participants
Time frame: Day 1 through Day 4
t1/2 of pociredir under fasted and fed conditions compared to healthy participants
Time frame: Day 1 through Day 4
Vz/F of pociredir under fasted and fed conditions compared to healthy participants
Time frame: Day 1 through Day 4
CL/F of pociredir under fasted and fed conditions compared to healthy participants
Time frame: Day 1 through Day 4
Results and safety
The study was stopped early (reason given: Sponsor decision). Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Jun 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
6 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing Pociredir in people with Sickle Cell Disease, run by Fulcrum Therapeutics at 6 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 8 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: stopped early, as of the sponsor's last update on 18 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 6 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study was stopped early (reason given: Sponsor decision). Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Plasma concentration of pociredir under fasted and fed conditions (time frame: Day 1 through Day 4). The study lists 10 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Jun 2026.