Sickle Cell DiseasePhase 2RESCUENCT07282210
Efficacy and Safety of SIL-8301 for Control of Hemolysis in a Uniform Sickle Cell Disease Endotype
A Phase 2 study testing Senicapoc in people with Sickle Cell Disease and Sickle Cell Anaemia, run by Biossil Inc. at 4 sites in Canada.
Trial summary
SIL-8301 (senicapoc) is being developed for the chronic treatment of patients with sickle cell disease in both adults and children. The purpose of this study is to compare the effects of senicapoc to placebo in patients with sickle cell disease that have had fewer than 2 acute sickle-related painful crises per year… Read more about this study
- Who is it for?
- Ages 16 to 50 years
- Conditions the study is for
- Sickle Cell Disease, Sickle Cell Anaemia, Sickle Cell Anemia
- What is being tested?
- Senicapoc
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 65 participants
- Where
- 4 sitesCanada
- Study dates
- Nov 2026to Oct 2031
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
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 16 to 50 years
- All sexes
- No healthy volunteers
- Child, Adult
Who may be able to join
- Documented diagnosis of sickle cell disease (SCD)
- 16-50 years of age
- Hemoglobin (Hb) ≤ 9.5 g/dL
- History of no more than 1 acute SCD-related painful crises requiring a visit to a medical facility per year within the preceding 2 years
- Steady-state hemolysis
- Current treatment with hydroxyurea
Who cannot join
- Receipt of senicapoc in a previous investigational study
- Current Red Blood Cell (RBC) transfusion or exchange transfusion program
- History of pulmonary hypertension
- Active cardiovascular, neurologic, endocrine, hepatic, or renal disorders
- Diagnosis of cancer (except non-melanoma skin cancer in situ, cervical cancer in situ, or breast cancer in situ) within the last 5 years
- History of liver disease
Trial locations and contacts
4 sites in 1 country. Contact the study team or a site near you to ask about taking part.
Canada4 sites, 4 recruiting
- Recruiting
Centre Hospitalier de l'Université de Montréal (CHUM)
Montreal, Quebec
- Recruiting
McGill University Health Centre
Montreal, Quebec
- Recruiting
The Hospital for Sick Children
Toronto, Ontario
- Recruiting
University Health Network, Toronto General Hospital
Toronto, Ontario
About this study
Official title: A Multicenter, Randomized, Double-blind, Placebo-controlled Study With an Open-label Extension to Determine Efficacy and Safety of SIL-8301 in Sickle Cell Disease (SCD) Patients With a Predominantly Hemolytic Phenotype
SIL-8301 (senicapoc) is being developed for the chronic treatment of patients with sickle cell disease in both adults and children. The purpose of this study is to compare the effects of senicapoc to placebo in patients with sickle cell disease that have had fewer than 2 acute sickle-related painful crises per year over the preceding 2 years, and have a predominantly hemolytic phenotype, defined as evidence of ongoing hemolysis and a baseline Hb of 9.5 g/dL or less, despite receiving hydroxyurea (an oral drug used for treatment of sickle cell disease) as standard of care. Participants will take senicapoc or matching placebo daily and continue on hydroxyurea as prescribed for up to 24 weeks. Eligible participants that complete the 24 weeks will have an opportunity to receive senicapoc for up to 2 years in an optional open label extension.
- Conditions
- Sickle Cell Disease, Sickle Cell Anaemia, Sickle Cell Anemia
- Being tested
- Senicapoc, Placebo
- Keywords
- senicapoc, Anemia, Hemolytic, Congenital, Anemia, Hemolytic, Anemia, Hematologic Diseases, Hemic and Lymphatic Diseases, Hemoglobinopathies, Genetic Diseases, Inborn, Congenital, Hereditary, and Neonatal Diseases and Abnormalities, Anemia, Sickle Cell, Anaemia, Sickle Cell
- Medical subject headings
- Anemia, Sickle Cell, Anemia, Hemolytic, Congenital, Anemia, Hemolytic, Anemia, Hematologic Diseases, Hemic and Lymphatic Diseases, Hemoglobinopathies, Genetic Diseases, Inborn
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
SenicapocDrug
Also called SIL-8301
10 mg tablets; administered at a loading dose of 20 mg twice daily for 4 days, followed by a maintenance dose of 10 mg once daily for up to 24 weeks
PlaceboDrug
Tablets similar in size and color; matching administration schedule
| Study group | Role | What they receive |
|---|---|---|
| Senicapoc (SIL-8301) | Experimental | 20 mg twice daily for 4 days, followed by 10 mg once daily for up to 24 weeks Receives: Drug: Senicapoc |
| Placebo | Placebo comparator | Matching placebo tablets twice daily for 4 days, followed by once daily for up to 24 weeks Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Hb response rate
Proportion of participants achieving an increase in Hb of > 1 g/dL from baseline
Measured: 24 Weeks
Secondary outcomes (11)
Change from baseline in Hb (g/dL)
Measured: 24 Weeks
Change from baseline in lactate dehydrogenase (LDH) (u/L)
Measured: 24 Weeks
Change from baseline in indirect bilirubin (µmol/L)
Measured: 24 Weeks
Change from baseline in reticulocyte count (%)
Measured: 24 Weeks
Proportion of participants with a Hb increase of > 2g/dL from baseline
Measured: 24 Weeks
Percent change from baseline in urine albumin-creatinine ratio (uACR)
Measured: 24 Weeks
Change from baseline in overall score and subscale domain scores of the Participant-Reported Outcomes Measurement Information System (PROMIS)
The PROMIS-29 assessment for adult participants assesses depressive symptoms, anxiety, physical function, pain interference, fatigue, sleep disturbance, and ability to participate in social roles and activities.
The PROMIS Pediatric-25 assessment for participants <18 years of age assesses depressive symptoms, anxiety, physical function and mobility, pain interference, fatigue, and peer relationships.
For both PROMIS assessments, a higher score indicates worse symptoms except for higher physical function values which indicate better physical function.
Measured: 24 Weeks
Sickle cell disease complication rate
Proportion of participants experiencing at least one new or worsening hemolytic complication at any time during the study
Measured: 24 Weeks
Proportion of participants with at least one category of improvement from baseline in Clinician and Patient Global Impression of Change
Measured: 24 Weeks
Frequency of acute sickle cell-related painful crises
Measured: 28 Weeks
Incidence of AEs, SAEs, and sickle cell disease related AEs
Measured: 28 Weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Dec 2025
- Study startNov 2026 (estimated)
- Primary completionOct 2029 (estimated)
- Study completionOct 2031 (estimated)
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 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 65 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Biossil Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07282210
- Sponsor's protocol ID
- SIL-8301-001
- Acronym
- RESCUE
- Status last verified
- Oct 2026
- First submitted
- 13 Nov 2025
- Last updated
- 2 Nov 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 2 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Multicenter, Randomized, Double-blind, Placebo-controlled Study With an Open-label Extension to Determine Efficacy and Safety of SIL-8301 in Sickle Cell Disease (SCD) Patients With a Predominantly Hemolytic Phenotype
- ClinicalTrials.gov ID
- NCT07282210
- Acronym / sponsor ID
- RESCUE / SIL-8301-001
- Conditions
- Sickle Cell Disease, Sickle Cell Anaemia, Sickle Cell Anemia
- Keywords
- senicapoc, Anemia, Hemolytic, Congenital, Anemia, Hemolytic, Anemia, Hematologic Diseases, Hemic and Lymphatic Diseases, Hemoglobinopathies, Genetic Diseases, Inborn
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 65 participants (estimated)
- Lead sponsor
- Biossil Inc.Industry (pharma, biotech, devices)
- Study start
- Nov 2026 (estimated)
- Primary completion
- Oct 2029 (estimated)
- Study completion
- Oct 2031 (estimated)
- First posted
- 15 Dec 2025 (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.
SIL-8301 (senicapoc) is being developed for the chronic treatment of patients with sickle cell disease in both adults and children. The purpose of this study is to compare the effects of senicapoc to placebo in patients with sickle cell disease that have had fewer than 2 acute sickle-related painful crises per year over the preceding 2 years, and have a predominantly hemolytic phenotype, defined as evidence of ongoing hemolysis and a baseline Hb of 9.5 g/dL or less, despite receiving hydroxyurea (an oral drug used for treatment of sickle cell disease) as standard of care. Participants will take senicapoc or matching placebo daily and continue on hydroxyurea as prescribed for up to 24 weeks. Eligible participants that complete the 24 weeks will have an opportunity to receive senicapoc for up to 2 years in an optional open label extension.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Senicapoc (SIL-8301) | Experimental | Drug: Senicapoc20 mg twice daily for 4 days, followed by 10 mg once daily for up to 24 weeks |
| Placebo | Placebo comparator | Drug: PlaceboMatching placebo tablets twice daily for 4 days, followed by once daily for up to 24 weeks |
Who may qualify
- Ages
- 16 to 50 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult
Key inclusion criteria (6 listed)
- Documented diagnosis of sickle cell disease (SCD)
- 16-50 years of age
- Hemoglobin (Hb) ≤ 9.5 g/dL
- History of no more than 1 acute SCD-related painful crises requiring a visit to a medical facility per year within the preceding 2 years
- Steady-state hemolysis
Key exclusion criteria (6 listed)
- Receipt of senicapoc in a previous investigational study
- Current Red Blood Cell (RBC) transfusion or exchange transfusion program
- History of pulmonary hypertension
- Active cardiovascular, neurologic, endocrine, hepatic, or renal disorders
- Diagnosis of cancer (except non-melanoma skin cancer in situ, cervical cancer in situ, or breast cancer in situ) within the last 5 years
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 |
|---|---|---|
| SenicapocAlso: SIL-830110 mg tablets; administered at a loading dose of 20 mg twice daily for 4 days, followed by a maintenance dose of 10 mg once daily for up to 24 weeks | Drug | Senicapoc (SIL-8301) |
| PlaceboTablets similar in size and color; matching administration schedule | Drug | Placebo |
Primary outcome
Hb response rate
Time frame: 24 Weeks
Proportion of participants achieving an increase in Hb of > 1 g/dL from baseline
11 secondary outcomes
Change from baseline in Hb (g/dL)
Time frame: 24 Weeks
Change from baseline in lactate dehydrogenase (LDH) (u/L)
Time frame: 24 Weeks
Change from baseline in indirect bilirubin (µmol/L)
Time frame: 24 Weeks
Change from baseline in reticulocyte count (%)
Time frame: 24 Weeks
Proportion of participants with a Hb increase of > 2g/dL from baseline
Time frame: 24 Weeks
Percent change from baseline in urine albumin-creatinine ratio (uACR)
Time frame: 24 Weeks
Change from baseline in overall score and subscale domain scores of the Participant-Reported Outcomes Measurement Information System (PROMIS)
Time frame: 24 Weeks
Sickle cell disease complication rate
Time frame: 24 Weeks
Proportion of participants with at least one category of improvement from baseline in Clinician and Patient Global Impression of Change
Time frame: 24 Weeks
Frequency of acute sickle cell-related painful crises
Time frame: 28 Weeks
Incidence of AEs, SAEs, and sickle cell disease related AEs
Time frame: 28 Weeks
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 2 Nov 2026.
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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.
4 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Senicapoc in people with Sickle Cell Disease and Sickle Cell Anaemia, run by Biossil Inc. at 4 sites in Canada.
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 6 inclusion and 6 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: looking for participants now, as of the sponsor's last update on 2 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 4 sites in Canada. 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. Some participants in this study may receive a placebo. 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 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Head of Clinical Operations ((978) 245-7397, trials@biossil.ai), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Hb response rate (time frame: 24 Weeks). 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 2 Nov 2026.