Sickle Cell Disease (SCD)Phase 2PHOENIXNCT05565092
Safety, Efficacy, Pharmacokinetic, and Pharmacodynamic Study of ALXN1820 in Adult Participants With Sickle Cell Disease
A Phase 2 study testing ALXN1820 in people with Sickle Cell Disease (SCD), run by Alexion Pharmaceuticals, Inc. at 2 sites in United States.
Trial summary
The primary objective of this study is to assess the safety and tolerability of ALXN1820 SC (subcutaneous) in participants with SCD (Sickle Cell Disease). Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Sickle Cell Disease (SCD)
- What is being tested?
- ALXN1820
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 2 participants
- Where
- 2 sitesUnited States
- Study dates
- 22 Feb 2023to 9 Jan 2024
- Phase
- Phase 2
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Confirmed diagnosis of SCD (HbSS, or HbSβ0-thalassemia).
- Body weight ≥ 40 kg (inclusive) at Screening.
- Must follow protocol-specified contraception guidance while on treatment and for up to 6 months after last dose.
- Hemoglobin between 5.5 and 10 g/dL at Screening
- Have had 1 to 10 VOCs in the past 12 months.
- Patients receiving hydroxyurea must have been on a stable dose for ≥ 3 months prior to providing informed consent, with no anticipated need for dose adjustment during the study.
- Patients will be vaccinated with MCV4 and serogroup B meningococcal vaccinations at least 14 days before dosing, if not already vaccinated within 3 years before the first dose.
- Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae vaccination are up to date according to current national/local vaccination guidelines for patients with SCD.
Who cannot join
- Planned initiation, termination, or dose alteration of hydroxyurea during the study.
- Receiving Voxelotor (OXBRYTA) or crizanlizumab (ADAKVEO) within 60 days of providing informed consent.
- Receiving treatment with recombinant human erythropoetins (eg, epoetin alfa).
- Treated with complement inhibitors within 6 months prior to the first dose.
- Patients who are on chronic transfusion or receive a transfusion within 60 days of first dose.
- Any significant disease or disorder which, in the opinion of the Investigator, may put the participant at risk.
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- Hepatitis B (positive hepatitis surface antigen [HBsAg] or positive core antibody (anti-HBc) with negative surface antibody [anti-HBs]) or hepatitis C viral infection (hepatitis C virus [HCV] antibody positive, except for patients with documented successful treatment and documented sustained virologic response) at Screening.
- Active systemic bacterial, viral, or fungal infection within 14 days prior to dosing.
- Participation (ie, last protocol-required study visit) in a clinical study within 90 days or 5 half-lives of the investigational agent, whichever is longer, before initiation of dosing on Day 1.
- Participation in more than 1 clinical study of a monoclonal antibody (mAb), or participation in a clinical study of a mAb within the 6 months or 5 half-lives of the mAb, whichever is longer, prior to Screening, during which the participant was exposed to the active study drug.
- Severe renal impairment (estimated glomerular filtration rate [eGFR] < 30 mL/min/1.73 m2 ) or on chronic dialysis.
- History of allergy or hypersensitivity to excipients of ALXN1820 (eg, polysorbate 80).
- History of complement deficiency.
- History of N meningitidis, S pneumoniae, or H influenzae infection.
- History of malignancy with the exception of a nonmelanoma skin cancer or carcinoma in situ of the cervix that has been treated with no evidence of recurrence within 5 years.
- Participants who are pregnant or breastfeeding.
Trial locations and contacts
2 sites in 1 country.
United States2 sites
Research Site
Hollywood, Florida, 33023
Research Site
Indianapolis, Indiana, 46260
About this study
Official title: A Phase 2a, Randomized, Open-Label Study to Evaluate Multiple Dosing Regimens of Subcutaneous ALXN1820 in Adult Participants With Sickle Cell Disease
The primary objective of this study is to assess the safety and tolerability of ALXN1820 SC (subcutaneous) in participants with SCD (Sickle Cell Disease).
- Conditions
- Sickle Cell Disease (SCD)
- Being tested
- ALXN1820
- Keywords
- Sickle Cell Disease, ALXN1820, SCD
- Medical subject headings
- Anemia, Sickle Cell
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ALXN1820Drug
ALXN1820 will be administered subcutaneously.
| Study group | Role | What they receive |
|---|---|---|
| ALXN1820 300 mg once weekly | Experimental | Participants will receive 300 milligrams (mg) once weekly (QW). Receives: Drug: ALXN1820 |
| ALXN1820 600 mg once every 4 weeks | Experimental | Participants will receive 600 mg once every 4 weeks (Q4W). Receives: Drug: ALXN1820 |
| ALXN1820 300 mg once every 2 weeks (Optional cohort) | Experimental | Participants will receive 300 mg once every 2 weeks (Q2W). Receives: Drug: ALXN1820 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of Participants With Treatment-Emergent Adverse Events and Serious Adverse Events
Measured: Baseline through Day 211 (Cohorts 1 and 2) and through Day 169 (Optional Cohort 3)
Secondary outcomes (8)
Pharmacokinetics: Serum ALXN1820 Concentration
Measured: Baseline through Day 211 (Cohorts 1 and 2) and through Day 169 (Optional Cohort 3)
Change From Baseline in Serum Concentration of Total and Free Properdin Through Day 211 (Cohorts 1 and 2) and Day 169 (Optional Cohort 3)
Measured: Baseline through Day 211 (Cohorts 1 and 2) and Day 169 (Optional Cohort 3)
Change From Baseline Complement Alternative Pathway Activity Through Day 211 (Cohorts 1 and 2) and Day 169 (Optional Cohort 3)
Measured: Baseline through Day 211 (Cohorts 1 and 2) and Day 169 (Optional Cohort 3)
Change From Baseline in Complement Biomarkers Through Week 12 (Cohorts 1 and 2)
Measured: Baseline, Week 12
Change From Baseline in Hemoglobin Level at Week 12 (Cohorts 1 and 2)
Measured: Baseline, Week 12
Change From Baseline in Hemolysis Markers at Week 12 (Cohorts 1 and 2)
Measured: Baseline, Week 12
Change From Baseline in Hemopexin at Week 12 (Cohorts 1 and 2)
Measured: Baseline, Week 12
Number of Participants With Antidrug Antibodies to ALXN1820
Measured: Baseline through Day 211 (Cohorts 1 and 2) and through Day 169 (Optional Cohort 3)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 Oct 2022
- Study start22 Feb 2023
- Primary completion9 Jan 2024
- Study completion9 Jan 2024
Why it stopped: Sponsor decision to terminate program.
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for Sickle Cell Disease (SCD)Studies of the same condition, open and under way.
- More trials run by Alexion Pharmaceuticals, Inc.The sponsor's other registered studies.
- 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
- None (open label)
- Enrolment
- 2 participants (actual)
Sponsor and investigators
- Lead sponsor
- Alexion Pharmaceuticals, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05565092
- Sponsor's protocol ID
- ALXN1820-SCD-201
- Other IDs
- 2022-001615-74
- Acronym
- PHOENIX
- Status last verified
- Jan 2025
- First submitted
- 15 Sep 2022
- Last updated
- 13 Jan 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: Alexion has a public commitment to allow requests for access to study data and will be supplying a protocol, CSR, and plain language summaries.
Study at a glance
From the registry record, last updated by the sponsor on 13 Jan 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 2a, Randomized, Open-Label Study to Evaluate Multiple Dosing Regimens of Subcutaneous ALXN1820 in Adult Participants With Sickle Cell Disease
- ClinicalTrials.gov ID
- NCT05565092
- Acronym / sponsor ID
- PHOENIX / ALXN1820-SCD-201
- Conditions
- Sickle Cell Disease (SCD)
- Keywords
- Sickle Cell Disease, ALXN1820, SCD
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: Sponsor decision to terminate program.
- Enrolment
- 2 participants (actual)
- Lead sponsor
- Alexion Pharmaceuticals, Inc.Industry (pharma, biotech, devices)
- Study start
- 22 Feb 2023 (actual)
- Primary completion
- 9 Jan 2024 (actual)
- Study completion
- 9 Jan 2024 (actual)
- First posted
- 4 Oct 2022 (actual)
- Results
- Posted 13 Jan 2025
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The primary objective of this study is to assess the safety and tolerability of ALXN1820 SC (subcutaneous) in participants with SCD (Sickle Cell Disease).
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| ALXN1820 300 mg once weekly | Experimental | Drug: ALXN1820Participants will receive 300 milligrams (mg) once weekly (QW). |
| ALXN1820 600 mg once every 4 weeks | Experimental | Drug: ALXN1820Participants will receive 600 mg once every 4 weeks (Q4W). |
| ALXN1820 300 mg once every 2 weeks (Optional cohort) | Experimental | Drug: ALXN1820Participants will receive 300 mg once every 2 weeks (Q2W). |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (8 listed)
- Confirmed diagnosis of SCD (HbSS, or HbSβ0-thalassemia).
- Body weight ≥ 40 kg (inclusive) at Screening.
- Must follow protocol-specified contraception guidance while on treatment and for up to 6 months after last dose.
- Hemoglobin between 5.5 and 10 g/dL at Screening
- Have had 1 to 10 VOCs in the past 12 months.
Key exclusion criteria (16 listed)
- Planned initiation, termination, or dose alteration of hydroxyurea during the study.
- Receiving Voxelotor (OXBRYTA) or crizanlizumab (ADAKVEO) within 60 days of providing informed consent.
- Receiving treatment with recombinant human erythropoetins (eg, epoetin alfa).
- Treated with complement inhibitors within 6 months prior to the first dose.
- Patients who are on chronic transfusion or receive a transfusion within 60 days of first dose.
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 |
|---|---|---|
| ALXN1820ALXN1820 will be administered subcutaneously. | Drug | ALXN1820 300 mg once every 2 weeks (Optional cohort), ALXN1820 300 mg once weekly, ALXN1820 600 mg once every 4 weeks |
Primary outcome
Number of Participants With Treatment-Emergent Adverse Events and Serious Adverse Events
Time frame: Baseline through Day 211 (Cohorts 1 and 2) and through Day 169 (Optional Cohort 3)
8 secondary outcomes
Pharmacokinetics: Serum ALXN1820 Concentration
Time frame: Baseline through Day 211 (Cohorts 1 and 2) and through Day 169 (Optional Cohort 3)
Change From Baseline in Serum Concentration of Total and Free Properdin Through Day 211 (Cohorts 1 and 2) and Day 169 (Optional Cohort 3)
Time frame: Baseline through Day 211 (Cohorts 1 and 2) and Day 169 (Optional Cohort 3)
Change From Baseline Complement Alternative Pathway Activity Through Day 211 (Cohorts 1 and 2) and Day 169 (Optional Cohort 3)
Time frame: Baseline through Day 211 (Cohorts 1 and 2) and Day 169 (Optional Cohort 3)
Change From Baseline in Complement Biomarkers Through Week 12 (Cohorts 1 and 2)
Time frame: Baseline, Week 12
Change From Baseline in Hemoglobin Level at Week 12 (Cohorts 1 and 2)
Time frame: Baseline, Week 12
Change From Baseline in Hemolysis Markers at Week 12 (Cohorts 1 and 2)
Time frame: Baseline, Week 12
Change From Baseline in Hemopexin at Week 12 (Cohorts 1 and 2)
Time frame: Baseline, Week 12
Number of Participants With Antidrug Antibodies to ALXN1820
Time frame: Baseline through Day 211 (Cohorts 1 and 2) and through Day 169 (Optional Cohort 3)
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 13 Jan 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Related InfoLink provided by the sponsor.
- Related InfoLink provided by the sponsor.
- Individual participant dataSharing planned: Yes. Alexion has a public commitment to allow requests for access to study data and will be supplying a protocol, CSR, and plain language summaries.
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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.
2 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 ALXN1820 in people with Sickle Cell Disease (SCD), run by Alexion Pharmaceuticals, Inc. at 2 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 16 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 13 Jan 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 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 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?
Yes. Results are posted in the registry (first posted 13 Jan 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
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?
Number of Participants With Treatment-Emergent Adverse Events and Serious Adverse Events (time frame: Baseline through Day 211 (Cohorts 1 and 2) and through Day 169 (Optional Cohort 3)). 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 13 Jan 2025.