Safety and Efficacy of ALXN1720 in Adults With Generalized Myasthenia Gravis
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ClinicalTrials.gov Identifier: NCT05556096 |
Recruitment Status :
Recruiting
First Posted : September 27, 2022
Last Update Posted : December 21, 2022
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Generalized Myasthenia Gravis | Combination Product: ALXN1720 Combination Product: Placebo | Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 254 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Intervention Model Description: | This is a treatment study with 2 parallel intervention groups. The study is blinded for sponsor staff, sponsor designees, investigative site personnel, other staff directly associated with the conduct of the study, and study participants. |
Masking: | Double (Participant, Investigator) |
Primary Purpose: | Treatment |
Official Title: | A Phase 3, Randomized, Double-blind, Placebo-controlled, Parallel, Multicenter Study to Evaluate the Safety and Efficacy of ALXN1720 in Adults With Generalized Myasthenia Gravis |
Actual Study Start Date : | November 21, 2022 |
Estimated Primary Completion Date : | July 1, 2025 |
Estimated Study Completion Date : | June 30, 2027 |

Arm | Intervention/treatment |
---|---|
Experimental: ALXN1720
Participants will receive a weight-based maintenance treatment with ALXN1720 on Day 1, followed by weight-based maintenance treatment of ALXN1720 on Week 1 (Day 8) and once every week (Q1W) thereafter for a total of 26 weeks. Following this randomized controlled treatment (RCT) period, all participants will receive ALXN1720 in an open-label extension (OLE) period of 96 weeks.
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Combination Product: ALXN1720
Combination product consisting of syringe prefilled with ALXN1720. |
Placebo Comparator: Placebo
Participants will receive placebo during the 26-week RCT period, after which they will enter the OLE period of the study and receive ALXN1720.
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Combination Product: Placebo
Combination product consisting of syringe prefilled with placebo. |
- Change From Baseline in Myasthenia Gravis-Activities of Daily Living (MG-ADL) Total Score at Week 26 [ Time Frame: Baseline, Week 26 ]
- Change From Baseline in Quantitative Myasthenia Gravis (QMG) Total Score at Week 26 [ Time Frame: Baseline, Week 26 ]
- Percentage of Responders Based on Reduction of the MG-ADL Total Score at Week 26 [ Time Frame: Baseline up to Week 26 ]Responders based on reduction by >= 3 points in the change from baseline in the MG-ADL total score at Week 26
- Percentage of Responders based on Reduction of the QMG Total Score at Week 26 [ Time Frame: Baseline up to Week 26 ]Responders based on reduction by >= 5 points in the change from baseline in the QMG total score at Week 26
- Change From Baseline in Myasthenia Gravis Composite (MGC) Total Score at Week 26 [ Time Frame: Baseline, Week 26 ]

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Diagnosis of MG with generalized muscle weakness meeting the clinical criteria defined by Myasthenia Gravis Foundation of America (MGFA) Class II, III or IV
- Positive serological test for autoantibodies against AChR.
Exclusion Criteria:
- History of thymectomy or any other thymic surgery within 12 months prior to Screening
- Untreated thymic malignancy, carcinoma, or thymoma
- History of Neisseria meningitidis infection
- Pregnancy, breastfeeding, or intention to conceive during the course of the study.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT05556096
Contact: AstraZeneca Clinical Study Information Center | 1-877-240-9479 | information.center@astrazeneca.com |
United States, Georgia | |
Research Site | Recruiting |
Gainesville, Georgia, United States, 30501 | |
United States, Kentucky | |
Research Site | Recruiting |
Lexington, Kentucky, United States, 40503 | |
United States, Nevada | |
Research Site | Recruiting |
Las Vegas, Nevada, United States, 89145 | |
United States, South Carolina | |
Research Site | Recruiting |
North Charleston, South Carolina, United States, 29406 | |
Spain | |
Research Site | Recruiting |
Madrid, Spain, 28034 | |
Research Site | Recruiting |
Madrid, Spain, 28046 | |
Research Site | Recruiting |
Pamplona, Spain, 31008 | |
Research Site | Recruiting |
San Sebastián de los Reyes, Spain, 28702 |
Responsible Party: | Alexion Pharmaceuticals |
ClinicalTrials.gov Identifier: | NCT05556096 |
Other Study ID Numbers: |
ALXN1720-MG-301 |
First Posted: | September 27, 2022 Key Record Dates |
Last Update Posted: | December 21, 2022 |
Last Verified: | December 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | Alexion has a public commitment to allow requests for access to study data and will be supplying a protocol, CSR, and plain language summaries. |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | Yes |
ALXN1720 anti-acetylcholine receptor antibody-positive acetylcholine receptor AChR generalized myasthenia gravis myasthenia gravis |
MG gMG complement component 5 C5 minibody VHH antibody |
Myasthenia Gravis Muscle Weakness Muscular Diseases Musculoskeletal Diseases Neuromuscular Manifestations Neurologic Manifestations Nervous System Diseases Pathologic Processes Paraneoplastic Syndromes, Nervous System Nervous System Neoplasms |
Neoplasms by Site Neoplasms Paraneoplastic Syndromes Autoimmune Diseases of the Nervous System Neurodegenerative Diseases Neuromuscular Junction Diseases Neuromuscular Diseases Autoimmune Diseases Immune System Diseases |