Overview
Sponsor-declared trial summary
Generalized Myasthenia Gravis
Phase 2: To evaluate the PD effect of povetacicept in subjects with gMG, Phase 2 and LTE: To evaluate the safety and tolerability of povetacicept in subjects with gMG
Key facts
- Sponsor
- Vertex Pharmaceuticals Inc.
- Participant type
- Patients
- Age range
- 18-64 years, 65+ years
- Gender
- Male and Female
- Therapeutic area
- Diseases [C] - Nervous System Diseases [C10]
- Trial duration
- 29 May 2026 → ongoing
- Decision date (initial)
- 2026-05-29
- Transition trial
- No
- Low-intervention
- No
- Rare-disease indication
- Yes
- Vulnerable population
- Yes
Trial design
CTIS Part I — objectives, methods, condition coding
Main objective
Scope: Pharmacodynamic, Safety
Phase 2: To evaluate the PD effect of povetacicept in subjects with gMG,
Phase 2 and LTE: To evaluate the safety and tolerability of povetacicept in subjects with gMG
Conditions and MedDRA coding
Generalized Myasthenia Gravis
| Version | Level | Code | Term | System organ class |
|---|---|---|---|---|
| 21.1 | PT | 10028417 | Myasthenia gravis | 100000004852 |
Eligibility criteria
Principal inclusion / exclusion criteria as submitted by sponsor
Inclusion criteria 3
- Age 18-80 years
- Diagnosis of generalized myasthenia gravis with generalized muscle weakness and fitting MGFA clinical classification II-IV
- Additional inclusion criteria are defined in the protocol
Exclusion criteria 3
- History of thymic surgery within 6 months of screening
- History of malignancy within the last 5 years
- Additional exclusion criteria are defined in the protocol
Endpoints
Primary and secondary outcome measures (English text)
Primary endpoints 2
- Phase 2: Percent change in total immunoglobulin G (IgG) [Time Frame: Baseline and At Week 12]
- Phase 2 and LTE: Safety and tolerability as Assessed by Number of Participants with Adverse Events (AEs) and Serious Adverse Events (SAEs)
Investigational products
Investigational medicinal products (IMPs), comparators, placebo, auxiliary
Test 1
ALPN-303 solution for injection in pre-filled syringe
PRD12198433 · Product
- Active substance
- Povetacicept
- Other product name
- Povetacicept
- Pharmaceutical form
- SOLUTION FOR INJECTION IN PRE-FILLED SYRINGE
- Route of administration
- SUBCUTANEOUS INJECTION
- Max daily dose
- 00 mg milligram(s)
- Max total dose
- 00 mg milligram(s)
- Max treatment duration
- 108 Week(s)
- Authorisation status
- Not Authorised
- MA holder
- VERTEX PHARMACEUTICALS, INCORPORATED
- Paediatric formulation
- No
- Orphan designation
- No
Placebo 1
Test IMP without active substance
N/A · Product
- Other product name
- N/A
- Pharmaceutical form
- N/A
- ATC code
- N/A — N/A
- Marketing authorisation
- N/A
- MA holder
- N/A
- MA country
- Iceland
- Paediatric formulation
- No
Sponsors and contacts
Sponsor organisations, regulatory contacts, third parties
Vertex Pharmaceuticals Inc.
- Sponsor organisation
- Vertex Pharmaceuticals Inc.
- Address
- 50 Northern Avenue
- City
- Boston
- Postcode
- 02210-1862
- Country
- United States
Scientific contact point
- Organisation
- Vertex Pharmaceuticals Inc.
- Contact name
- Clinical Trials and Medical Info
Public contact point
- Organisation
- Vertex Pharmaceuticals Inc.
- Contact name
- Clinical Trials and Medical Info
Third parties 1
| Organisation | City, country | Duties |
|---|---|---|
| Parexel International (IRL) Limited ORG-100022780
|
Dublin 2, Ireland | On site monitoring, Code 10, Code 11, Code 12, Code 13, Code 2, Code 5, Data management, Code 8, Code 9 |
Locations
1 EU/EEA country · 7 investigational sites
By country
| Country | MS status | Planned subjects | Sites |
|---|---|---|---|
| Poland | Authorised, recruiting | 5 | 7 |
| Rest of world
United States, Australia, United Kingdom, Turkey
|
— | 25 | — |
Investigational sites
Country notifications
Trial-start, recruitment-start, end and early-termination notifications submitted per Member State
| Country | Trial start | Trial end | Recruitment start | Recruitment end | Early termination |
|---|---|---|---|---|---|
| Poland | 2026-05-29 |
Results and documents
Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial
Documents 11 files
Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.
| Type | Title | Version |
|---|---|---|
| Protocol (for publication) | D1_Protocol Main English VX25-AIS-301 Public | 2.2 |
| Protocol (for publication) | D4_Rating Scale Placeholder English VX25-AIS-301 Public | 2.0 |
| Recruitment arrangements (for publication) | K1_POL Recruitment Procedure Description VX25-AIS-301 Public | 2.1 |
| Recruitment arrangements (for publication) | K2_POL Recruitment Brochure Polish VX25-AIS-301 Public | 2.0 |
| Recruitment arrangements (for publication) | K2_POL Recruitment Dear Patient Letter Polish VX25-AIS-301 Public | 2.0 |
| Recruitment arrangements (for publication) | K2_POL Recruitment Other Consent Navigator English VX25-AIS-301 Public | 2.0 |
| Recruitment arrangements (for publication) | K2_POL Recruitment Telephone Script Polish VX25-AIS-301 Public | 1.0 |
| Subject information and informed consent form (for publication) | L1_POL Country ICF Main Adult LTE Polish VX25-AIS-301 Public | 2.1 |
| Subject information and informed consent form (for publication) | L1_POL Country ICF Main Adult Phase 2 Polish VX25-AIS-301 Public | 2.1 |
| Subject information and informed consent form (for publication) | L1_POL Country ICF Pregnant Form Adult Polish VX25-AIS-301 Public | 2.1 |
| Synopsis of the protocol (for publication) | D1_POL Lay Protocol Synopsis Main Polish VX25-AIS-301 Public | 2.2 |
Application history
1 submissions — initial application plus substantial / non-substantial modifications
| # | Type | Code | Submitted | Reference MS | Conclusion | Decision date |
|---|---|---|---|---|---|---|
| 1 | INITIAL | IN | 2026-02-13 | Poland | Acceptable 2026-05-25
|
2026-05-29 |