CompletedNCT04631562Updated Aug 20, 2024Results posted

Study of ALXN1820 in Healthy Adult Participants

A Phase 1 interventional study of ALXN1820 SC and ALXN1820 IV in Healthy, sponsored by Alexion Pharmaceuticals, Inc.. Completed at 3 sites in 2 countries. Per ClinicalTrials.gov, last updated 2024-08-20.

Sponsored by Alexion Pharmaceuticals, Inc. · Phase 1, Interventional, and Basic science

Phase: Phase 1
Study type: Interventional
Enrollment: 66
Allocation: Randomized
Sex: All

Study summary

This is a Phase 1, randomized, double-blind, placebo-controlled single and multiple ascending dose study designed to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and immunogenicity of ALXN1820 administered subcutaneously (SC) (ALXN1820 SC) and intravenously (IV) (ALXN1820 IV).

Read the detailed description

This study will include up to 10 different dosing cohorts, with each cohort consisting of 2 groups (ALXN1820 group, placebo group). Participants will be randomly assigned in a 3:1 ratio to each of these 2 groups, respectively, within all 10 cohorts, to receive either a single or multiple doses of ALXN1820 SC, a single dose of ALXN1820 IV, or a single or multiple doses of placebo.

The study will be conducted in healthy adult participants and will also include a multiple SC dose cohort in healthy participants of Japanese descent.

Conditions studied

Healthy

Keywords

ALXN1820
Properdin
Pharmacodynamics
Pharmacokinetics

In context

Lead sponsor

Alexion Pharmaceuticals, Inc. is the lead sponsor of 249 studies on the registry; 25 are open to participants now.

Of its 98 completed or terminated interventional studies of FDA-regulated products, 70 (71%) have results posted.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: Child (0–17), Adult (18–64), Older adult (65+)
Sexes eligible: All
Accepts healthy volunteers: Yes

Inclusion criteria

Body weight 50 to 100 kilograms (kg); body mass index 17 to 32 kg/meter squared.
Cohort 9 only: Japanese participants (defined as those participants whose parents and grandparents are both Japanese and who have spent less than 5 years outside of Japan).
Satisfactory medical assessment.
Must follow protocol-specified contraception guidance while on treatment and for up to 6 months after last dose.
Vaccination requirement:
- Vaccination with tetravalent meningococcal conjugate vaccine at least 56 days and not more than 2 years, 6 months prior to dosing;
- Vaccination with serogroup B meningococcal vaccine at least 56 days prior to dosing, with a booster at least 28 days prior to dosing, with at least 28 days between the first and second injections.

Exclusion criteria

Exclusion Criteria:

Current/recurrent diseases or relevant medical history.
History of any Neisseria infection.
Hepatitis B/C, human immunodeficiency virus.
History of latent or active tuberculosis (TB), or positive TB test.
Active systemic infection within 14 days of dosing.
Risk of meningococcal infections due to living/working conditions.
History of complement deficiency or complement activity below the reference range.
Participation 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.
Acquired complement deficiencies (for example, those receiving eculizumab).

Study design

Phase: Phase 1
Primary purpose: Basic science
Allocation: Randomized
Intervention model: Sequential assignment
Masking: Double (Participant, Investigator)
Enrollment: 66 participants (actual)

Study arms

Experimental
ALXN1820
Participants will receive ALXN1820 SC or ALXN1820 IV according to their assigned cohort. ALXN1820 SC will be evaluated in single and multiple ascending doses while ALXN1820 IV will be evaluated in a single dose cohort only.
Drug: ALXN1820 SC · Drug: ALXN1820 IV
Placebo comparator
Placebo
Participants will receive Placebo SC or Placebo IV according to their assigned cohort.
Drug: Placebo SC · Drug: Placebo IV

Interventions

DrugALXN1820 SC
ALXN1820 SC will be administered as a manual SC push or SC infusion via a syringe pump. Doses will range from 12.5 milligrams (mg) to a maximum of 2250 mg. Multiple dosing duration will range from 3 to 5 weeks.
DrugALXN1820 IV
ALXN1820 IV (450 mg) will be administered as an IV infusion.
DrugPlacebo SC
Placebo SC will be administered as a manual SC push or SC infusion via a syringe pump.
DrugPlacebo IV
Placebo IV will be administered as an IV infusion.

What researchers measure

Primary outcomes

Number of Participants With Treatment-related Adverse Events (TEAEs) For ALXN1820 SC And ALXN1820 IV
An adverse event (AE) was defined as any unfavorable and unintended sign (for example, including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal product or procedure, whether or not considered related to the medicinal product or procedure, which occurred during the course of the clinical study. TEAEs were defined as any AEs that commenced after the start of administration of study intervention. Serious AEs (SAEs) were defined as any untoward medical occurrence that met at least 1 of the following serious criteria: resulted in death, was life-threatening, required in-patient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect, other medically important serious event. A summary of all SAEs and Other AEs (nonserious) regardless of causality is located in the 'Reported AEs' Section.
Time frame: Cohorts 1 to 6: Baseline up to Day 127; Cohorts 8 to 9: Baseline up to Day 155

Secondary outcomes

Area Under The Concentration-time Curve (AUC) From Time 0 (Dosing) To Time Infinity (AUC0-inf) And AUC During The Dosing Interval (AUCtau) of Serum ALXN1820 For Single Dose Cohorts
Time frame: Up to 126 days following the first day of dosing
Area Under The Concentration-time Curve During The Dosing Interval (AUCtau) Of Serum ALXN1820 For Multiple Dose Cohorts
Time frame: Up to 154 days following the first day of dosing
Maximum Observed Serum Concentration (Cmax) Of Serum ALXN1820 For Single Dose Cohorts
Time frame: Up to 126 days following the first day of dosing
Maximum Observed Serum Concentration (Cmax) Of Serum ALXN1820 For Multiple Dose Cohorts
Time frame: Up to 154 days following the first day of dosing
Change From Baseline in Serum Concentrations Of Total Properdin For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts
Time frame: Baseline, Day 127
Change From Baseline in Serum Concentrations Of Free Properdin For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts
Time frame: Baseline, Day 127
Change From Baseline In Serum Concentrations of Total Properdin For ALXN1820 SC- Multiple Dose Cohorts
Time frame: Baseline, Day 155
Change From Baseline In Serum Concentrations of Free Properdin For ALXN1820 SC- Multiple Dose Cohorts
Time frame: Baseline, Day 155
Change From Baseline In Complement Alternative Pathway (CAP) Activity Using The Wieslab Alternative Pathway (AP) Assay For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts
Time frame: Baseline, Day 127
Change From Baseline In Complement Alternative Pathway Activity Using The Wieslab Alternative Pathway Assay For ALXN1820 SC- Multiple Dose Cohorts
Time frame: Baseline, Day 155
Number Of Participants With Positive Antidrug Antibodies (ADAs) To ALXN1820 SC And ALXN1820 IV
Time frame: Baseline up to Day 155
Absolute Bioavailability Of ALXN1820 SC
The absolute bioavailability was expressed as ratio and was calculated as the geometric mean for the AUC\[0-inf\] for SC divided by the geometric mean for the AUC\[0-inf\] for IV. Least square means were calculated with cohort, treatment, and sequence as the fixed effects, and participant-participant (sequence) as a random effect.
Time frame: Baseline up to Day 127

Results

Posted Mar 15, 2024

Participant flow

Participant flow — Overall Study
Milestone	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)	All Placebo
Started	5	6	5	5	5	6	7	6	15
Received at least 1 dose of study drug	5	6	5	5	5	6	7	6	15
Completed	5	6	5	4	5	6	6	5	14
Not completed	0	0	0	1	0	0	1	1	1
Withdrew: Withdrawal by subject	0	0	0	0	0	0	0	1	0
Withdrew: Other	0	0	0	0	0	0	0	0	1
Withdrew: Lost to follow-up	0	0	0	1	0	0	0	0	0
Withdrew: Adverse event	0	0	0	0	0	0	1	0	0

Outcome measures

PrimaryNumber of Participants With Treatment-related Adverse Events (TEAEs) For ALXN1820 SC And ALXN1820 IV

An adverse event (AE) was defined as any unfavorable and unintended sign (for example, including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal product or procedure, whether or not considered related to the medicinal product or procedure, which occurred during the course of the clinical study. TEAEs were defined as any AEs that commenced after the start of administration of study intervention. Serious AEs (SAEs) were defined as any untoward medical occurrence that met at least 1 of the following serious criteria: resulted in death, was life-threatening, required in-patient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect, other medically important serious event. A summary of all SAEs and Other AEs (nonserious) regardless of causality is located in the 'Reported AEs' Section.

Time frame:: Cohorts 1 to 6: Baseline up to Day 127; Cohorts 8 to 9: Baseline up to Day 155
Reported as:: Count of participants · Participants

Number of Participants With Treatment-related Adverse Events (TEAEs) For ALXN1820 SC And ALXN1820 IV
Participants	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)	All Placebo
Number of Participants With Treatment-related Adverse Events (TEAEs) For ALXN1820 SC And ALXN1820 IV	1	0	0	4	2	0	1	3	2

SecondaryArea Under The Concentration-time Curve (AUC) From Time 0 (Dosing) To Time Infinity (AUC0-inf) And AUC During The Dosing Interval (AUCtau) of Serum ALXN1820 For Single Dose Cohorts

Time frame:: Up to 126 days following the first day of dosing
Reported as:: Geometric mean · hours*micrograms/milliliters

Area Under The Concentration-time Curve (AUC) From Time 0 (Dosing) To Time Infinity (AUC0-inf) And AUC During The Dosing Interval (AUCtau) of Serum ALXN1820 For Single Dose Cohorts
hours*micrograms/milliliters	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC
AUC0-inf	1708.745740 ± NA	11871.887397 ± 18.11	22447.444516 ± 24.22	65994.232565 ± 23.56	70222.568018 ± 13.41	157445.098602 ± 15.80
AUCtau	1301.090561 ± 35.33	11356.654811 ± 18.25	21767.138401 ± 24.61	56467.567738 ± 37.45	69126.480691 ± 13.16	151825.555391 ± 15.02

SecondaryArea Under The Concentration-time Curve During The Dosing Interval (AUCtau) Of Serum ALXN1820 For Multiple Dose Cohorts

Time frame:: Up to 154 days following the first day of dosing
Reported as:: Geometric mean · hours*micrograms/milliliters

Area Under The Concentration-time Curve During The Dosing Interval (AUCtau) Of Serum ALXN1820 For Multiple Dose Cohorts
hours*micrograms/milliliters	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)
Area Under The Concentration-time Curve During The Dosing Interval (AUCtau) Of Serum ALXN1820 For Multiple Dose Cohorts	13047.247486 ± 11.96	14895.697459 ± 6.63

SecondaryMaximum Observed Serum Concentration (Cmax) Of Serum ALXN1820 For Single Dose Cohorts

Time frame:: Up to 126 days following the first day of dosing
Reported as:: Geometric mean · micrograms/milliliters

Maximum Observed Serum Concentration (Cmax) Of Serum ALXN1820 For Single Dose Cohorts
micrograms/milliliters	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC
Maximum Observed Serum Concentration (Cmax) Of Serum ALXN1820 For Single Dose Cohorts	2.346 ± 17.85	12.892 ± 10.48	29.342 ± 22.53	99.256 ± 33.98	162.518 ± 46.73	246.140 ± 17.14

SecondaryMaximum Observed Serum Concentration (Cmax) Of Serum ALXN1820 For Multiple Dose Cohorts

Time frame:: Up to 154 days following the first day of dosing
Reported as:: Geometric mean · micrograms/milliliters

Maximum Observed Serum Concentration (Cmax) Of Serum ALXN1820 For Multiple Dose Cohorts
micrograms/milliliters	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)
Maximum Observed Serum Concentration (Cmax) Of Serum ALXN1820 For Multiple Dose Cohorts	90.53 ± 12.40	100.97 ± 7.94

SecondaryChange From Baseline in Serum Concentrations Of Total Properdin For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts

Time frame:: Baseline, Day 127
Reported as:: Mean · micrograms/milliliters

Change From Baseline in Serum Concentrations Of Total Properdin For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts
micrograms/milliliters	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC	Placebo
Change From Baseline in Serum Concentrations Of Total Properdin For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts	3.744 ± 0.8941	2.093 ± 1.3870	1.788 ± 1.7589	5.580 ± 3.1652	3.014 ± 2.0181	15.017 ± 7.1687	1.240 ± 1.4712

SecondaryChange From Baseline in Serum Concentrations Of Free Properdin For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts

Time frame:: Baseline, Day 127
Reported as:: Mean · nanograms/milliliters

Change From Baseline in Serum Concentrations Of Free Properdin For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts
nanograms/milliliters	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC	Placebo
Change From Baseline in Serum Concentrations Of Free Properdin For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts	848.0 ± 508.40	1096.7 ± 1815.02	1200.0 ± 1078.61	20.8 ± 2667.17	1188.4 ± 975.93	5171.8 ± 910.95	-26.6 ± 1749.15

SecondaryChange From Baseline In Serum Concentrations of Total Properdin For ALXN1820 SC- Multiple Dose Cohorts

Time frame:: Baseline, Day 155
Reported as:: Mean · micrograms/milliliters

Change From Baseline In Serum Concentrations of Total Properdin For ALXN1820 SC- Multiple Dose Cohorts
micrograms/milliliters	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)	All Placebo
Change From Baseline In Serum Concentrations of Total Properdin For ALXN1820 SC- Multiple Dose Cohorts	6.018 ± 2.5094	9.878 ± 1.6731	0.418 ± 0.2806

SecondaryChange From Baseline In Serum Concentrations of Free Properdin For ALXN1820 SC- Multiple Dose Cohorts

Time frame:: Baseline, Day 155
Reported as:: Mean · nanograms/milliliters

Change From Baseline In Serum Concentrations of Free Properdin For ALXN1820 SC- Multiple Dose Cohorts
nanograms/milliliters	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)	All Placebo
Change From Baseline In Serum Concentrations of Free Properdin For ALXN1820 SC- Multiple Dose Cohorts	3775.2 ± 1480.18	3762.0 ± 796.41	154.5 ± 480.34

SecondaryChange From Baseline In Complement Alternative Pathway (CAP) Activity Using The Wieslab Alternative Pathway (AP) Assay For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts

Time frame:: Baseline, Day 127
Reported as:: Mean · percentage of activity

Change From Baseline In Complement Alternative Pathway (CAP) Activity Using The Wieslab Alternative Pathway (AP) Assay For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts
percentage of activity	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC	Placebo
Change From Baseline In Complement Alternative Pathway (CAP) Activity Using The Wieslab Alternative Pathway (AP) Assay For ALXN1820 SC And ALXN1820 IV-Single Dose Cohorts	-15.6800 ± 19.06770	5.0833 ± 28.14281	1.6600 ± 18.75241	10.3750 ± 35.92282	3.100 ± 23.43683	6.6500 ± 20.32956	5.8091 ± 25.66349

SecondaryChange From Baseline In Complement Alternative Pathway Activity Using The Wieslab Alternative Pathway Assay For ALXN1820 SC- Multiple Dose Cohorts

Time frame:: Baseline, Day 155
Reported as:: Mean · percentage of activity

Change From Baseline In Complement Alternative Pathway Activity Using The Wieslab Alternative Pathway Assay For ALXN1820 SC- Multiple Dose Cohorts
percentage of activity	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)	All Placebo
Change From Baseline In Complement Alternative Pathway Activity Using The Wieslab Alternative Pathway Assay For ALXN1820 SC- Multiple Dose Cohorts	27.9714 ± 34.63436	2.6667 ± 25.02420	7.0000 ± 15.05169

SecondaryNumber Of Participants With Positive Antidrug Antibodies (ADAs) To ALXN1820 SC And ALXN1820 IV

Time frame:: Baseline up to Day 155
Reported as:: Count of participants · Participants

Number Of Participants With Positive Antidrug Antibodies (ADAs) To ALXN1820 SC And ALXN1820 IV
Participants	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)	All Placebo
Number Of Participants With Positive Antidrug Antibodies (ADAs) To ALXN1820 SC And ALXN1820 IV	0	0	0	0	0	0	2	1	0

SecondaryAbsolute Bioavailability Of ALXN1820 SC

The absolute bioavailability was expressed as ratio and was calculated as the geometric mean for the AUC\[0-inf\] for SC divided by the geometric mean for the AUC\[0-inf\] for IV. Least square means were calculated with cohort, treatment, and sequence as the fixed effects, and participant-participant (sequence) as a random effect.

Time frame:: Baseline up to Day 127
Reported as:: Geometric least squares mean · Ratio

Absolute Bioavailability Of ALXN1820 SC
Ratio	Cohort 4: ALXN1820 450 mg SC
Absolute Bioavailability Of ALXN1820 SC	89.307 (67.806 to 117.625)

Adverse events

Collected over Baseline up to Day 155. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
Group	Deaths	Serious	Other
Cohort 1: ALXN1820 12.5 mg SC	0/5 (0%)	0/5 (0%)	4/5 (80%)
Cohort 2: ALXN1820 50 mg SC	0/6 (0%)	0/6 (0%)	6/6 (100%)
Cohort 3: ALXN1820 150 mg SC	0/5 (0%)	0/5 (0%)	2/5 (40%)
Cohort 4: ALXN1820 450 mg SC	0/5 (0%)	0/5 (0%)	4/5 (80%)
Cohort 5: ALXN1820 450 mg IV	0/5 (0%)	0/5 (0%)	4/5 (80%)
Cohort 6: ALXN1820 1200 mg SC	0/6 (0%)	0/6 (0%)	6/6 (100%)
Cohort 8: ALXN1820 150 mg SC (QW*5)	0/7 (0%)	0/7 (0%)	6/7 (85.7%)
Cohort 9: ALXN1820 150 mg SC (QW*5)	0/6 (0%)	0/6 (0%)	5/6 (83.3%)
All Placebo	0/15 (0%)	0/15 (0%)	11/15 (73.3%)

Most frequent other events

Showing 10 of 72

Most frequent other events
Event	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)	All Placebo
HeadacheNervous system disorders	0/5	1/6	0/5	3/5	2/5	1/6	1/7	0/6	3/15
COVID-19Infections and infestations	0/5	0/6	0/5	0/5	1/5	3/6	3/7	0/6	2/15
Viral upper respiratory tract infectionInfections and infestations	0/5	0/6	0/5	0/5	0/5	3/6	2/7	0/6	1/15
NasopharyngitisInfections and infestations	0/5	0/6	0/5	0/5	2/5	1/6	0/7	0/6	0/15
NauseaGastrointestinal disorders	1/5	0/6	1/5	2/5	0/5	0/6	0/7	0/6	1/15
Infusion site erythemaGeneral disorders	0/5	0/6	0/5	2/5	0/5	0/6	0/7	0/6	0/15
Neck painMusculoskeletal and connective tissue disorders	0/5	1/6	0/5	2/5	0/5	0/6	0/7	0/6	0/15
Upper respiratory tract infectionInfections and infestations	1/5	2/6	0/5	0/5	0/5	0/6	1/7	0/6	3/15
VomitingGastrointestinal disorders	1/5	0/6	0/5	0/5	0/5	2/6	0/7	0/6	0/15
DiarrhoeaGastrointestinal disorders	1/5	1/6	0/5	0/5	0/5	0/6	1/7	0/6	4/15

Baseline characteristics

The Safety Set included all participants who received at least 1 dose of study drug.

Age, Categorical
Age, Categorical(Participants)	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)	All Placebo	Total
<=18 years	0	0	0	0	0	0	0	0	0	0
Between 18 and 65 years	5	6	5	5	5	6	7	6	15	60
>=65 years	0	0	0	0	0	0	0	0	0	0

Sex: Female, Male
Sex: Female, Male(Participants)	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)	All Placebo	Total
Female	3	6	1	3	2	3	5	0	9	32
Male	2	0	4	2	3	3	2	6	6	28

Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)	All Placebo	Total
Hispanic or Latino	0	1	0	0	0	0	0	0	1	2
Not Hispanic or Latino	5	4	5	4	3	6	7	6	12	52
Unknown or Not Reported	0	1	0	1	2	0	0	0	2	6

Race (NIH/OMB)
Race (NIH/OMB)(Participants)	Cohort 1: ALXN1820 12.5 mg SC	Cohort 2: ALXN1820 50 mg SC	Cohort 3: ALXN1820 150 mg SC	Cohort 4: ALXN1820 450 mg SC	Cohort 5: ALXN1820 450 mg IV	Cohort 6: ALXN1820 1200 mg SC	Cohort 8: ALXN1820 150 mg SC (QW*5)	Cohort 9: ALXN1820 150 mg SC (QW*5)	All Placebo	Total
American Indian or Alaska Native	0	0	0	0	0	0	0	0	0	0
Asian	2	1	0	0	0	0	0	6	3	12
Native Hawaiian or Other Pacific Islander	0	0	1	0	0	0	0	0	0	1
Black or African American	0	0	0	0	0	0	0	0	1	1
White	3	5	4	3	5	5	7	0	11	43
More than one race	0	0	0	2	0	1	0	0	0	3
Unknown or Not Reported	0	0	0	0	0	0	0	0	0	0

Study locations

3 sites

Research Site
Herston, 4006, Australia
Research Site
London, SE1 1YR, United Kingdom
Research Site
London, SE5 9RS, United Kingdom

References and documents

Study documents

Study protocol · Jul 6, 2021
Statistical analysis plan · Nov 28, 2022

Documents are hosted by the registry — open the source record to download them.

Individual participant data

Plan to share: No

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on Aug 20, 2024, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT04631562
Lead sponsor: Alexion Pharmaceuticals, Inc.
Collaborators: Syneos Health
Responsible party: Sponsor
First posted: Nov 17, 2020
Start date: Jan 13, 2021
Primary completion: Sep 1, 2022
Completion: Sep 1, 2022
Results posted: Mar 15, 2024
Last update: Aug 20, 2024

Oversight

Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Jul 2024. You cannot join it, but the record below documents what was studied.

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Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

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Alexion Pharmaceuticals, Inc.

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