Phase 2a Study of ALXN1920 in PMN

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Alexion Pharmaceuticals Inc.

Participant type

Patients

Age range

18-64 years, 65+ years

Gender

Male and Female

Therapeutic area

Diseases [C] - Immune System Diseases [C20]

Trial duration

26 Nov 2025 → ongoing

Decision date (initial)

2025-11-24

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: Safety, Others, Efficacy, Pharmacokinetic, Pharmacodynamic

To evaluate the efficacy of ALXN1920 compared with placebo in participants with PMN who are at a high risk for disease progression using 24-hour UPCR

Secondary objectives 6

1. To evaluate the additional efficacy of ALXN1920 compared with placebo in participants with PMN who are at a high risk for disease progression
2. To evaluate ALXN1920 compared with placebo in participants with PMN who are at a high risk for disease progression using biomarkers in urine
3. To assess the safety and tolerability of ALXN1920 in participants with PMN who are at high risk for disease progression
4. To characterize the PK of ALXN1920 in participants with PMN who are at a high risk for disease progression
5. To characterize the PD of ALXN1920 in participants with PMN who are at a high risk for disease progression
6. To assess the immunogenicity of ALXN1920 in participants with PMN who are at a high risk for disease progression and are treated with ALXN1920

Conditions and MedDRA coding

Primary Mebranous Nephropathy (PMN)

Study design 1 period

Regulatory references

Scientific advice from competent authorities

Food And Drug Administration

Plan to share IPD

Yes

IPD plan description

Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal Vivli.org. All requests will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure. Yes, indicates that AZ are accepting requests for IPD, but this does not mean all requests will be shared. AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA PhRMA Data Sharing Principles. When a request has been approved AstraZeneca will provide access to the anonymized individual patient-level data via secure research environment https://vivli.org/. Signed Data Usage Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information.

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 10

1. Participant must be ≥18 and ≤75 years of age at the time of signing the informed consent.
2. Participants who have a documented diagnosis of PMN, established by positive anti PLA2R antibody level (≥ 20 RU/mL) at Screening, which must be confirmed by a central laboratory.
3. Participants at high risk for disease progression, defined as: a. Receiving ACE inhibitors or ARB for a minimum of 8 weeks prior to Screening, with the dose titrated to the maximally tolerated level; however, participants with less than 8 weeks on ACE or ARB before Screening or who have not yet reached maximally tolerated dose will enter the Run-in Period for up to 8 weeks, b. Participants who are on ACE inhibitors or ARB for a minimum of 8 weeks with SBP < 140 mmHg in ≥ 75% of the readings (within the last 8 weeks) are allowed to be randomized, and c. Having two proteinuria measurements by either a 24-hour urine collection or a spot urine with each > 3.5 g/day, the second measurement showing ≤50% decrease from the first measurement.
4. eGFR ≥ 60 mL/min/1.73 m2 during Screening calculated by CKD-EPI 2021 creatinine formula.
5. Male or female assigned at birth, inclusive of all gender identities.
6. Agree to follow protocol-specified contraception guidance.
7. Signed informed consent as described in protocol which includes compliance with the requirements and restrictions listed in the ICF and in this protocol.
8. Provision of signed and dated written Optional Genetic Research Information informed consent prior to collection of samples for optional genetic research that supports the Genomic Initiative.
9. Participants are willing to receive the background SoC.
10. To reduce the risk of infections, all participants must receive prophylactic treatment with appropriate antibiotics while receiving RTX and be willing to be vaccinated against Neisseria meningitidis.

Exclusion criteria 39

1. History of malignancy within 5 years prior to Screening with the exception of nonmelanoma skin cancer or carcinoma in situ of the cervix that has been treated with no evidence of recurrence.
2. History of hypersensitivity to any ingredient contained in the study intervention, including inability to take or tolerate the allowed concomitant therapies.
3. Documented rapid deterioration of kidney function (20% or greater decline in eGFR sustained over a period of at least 3 months within 24 months before Screening)
4. Participants with BMI > 40.
5. Uncontrolled HTN, defined as BP ≥ 140 mm Hg systolic and/or ≥ 90 mm Hg diastolic on ≥3 BP medications.
6. Laboratory abnormalities at Screening, including: • ALT > 2 × ULN • Direct bilirubin > 2 × ULN • HbA1c at Screening > 6.5%
7. Any other clinically significant laboratory abnormality that, in the opinion of the Investigator, would make the participant inappropriate for the study or put the participant at undue risk.
8. A history of Diabetes Mellitus Type 1 and diagnosis of Diabetes Mellitus Type 2.
9. Current treatment with a biologic medication that may affect immune system functioning or previous treatment with a biologic medication that may affect immune system functioning stopped within 30 days or 5 terminal half-lives of the biologic medication, whichever is longer, prior to Screening Visit.
10. Any previous or current treatment with complement inhibitors (including but not limited to, eculizumab, ravulizumab).
11. Presence of hepatitis B surface antigen (HBsAg) and/or HBV DNA positive at Screening or documented within preceding 3 months. NOTE: a. Participants with known positive HBsAb may be randomized provided they are hepatitis B-vaccinated and have negative HBsAg and HBcAb. b. Participants with isolated anti-HBc positivity (total anti-HBc positive, HBsAg negative) may be randomized if they have negative HBV DNA during the Screening period. c. Participants with evidence of past resolved HBV infection (HBcAb/anti HBc positive and anti HBs positive) may be randomized if HBV DNA is negative; document past infection in Medical History).
12. Anti-CD20 antibody use within 6 months prior to Screening.
13. Participants who are receiving or have received obinutuzumab.
14. Cyclophosphamide use within 6 months prior to Screening.
15. History of life-threatening Nephrotic Syndrome (serum albumin <2.5 g/dL AND either treatment refractory edema or thromboembolic event) within 1 year before Screening.
16. Immunosuppressants other than anti-CD20 antibody or cyclophosphamide used within 12 weeks prior to Screening.
17. Participants who are unable to take at least 1 antimicrobial agent used to prevent N meningitidis.
18. Participation in another investigational drug or investigational device study within 30 days before initiation of study intervention on Day 1 in this study or within 5 half-lives of that investigational product, whichever is greater.
19. Pregnant, breastfeeding, or intending to conceive during the course of the study.
20. History of resistance to RTX defined as one of the following: • having a reduction in proteinuria of <25% after 6 months of treatment with RTX (including any increase in proteinuria), or, • reduction in anti-PLA2R antibody levels < 25% at 3 months, or < 50% at 6 months, after treatment with RTX Note: Participants who previously responded to RTX with either a CR or PR but relapsed at least 6 months after last RTX dose are eligible (relapse is defined as a return of proteinuria to > 3.5 g/day after an initial CR or PR to immunosuppressive therapy
21. History of intolerance or hypersensitivity to ACEi or ARB, including but not limited to angioedema, persistent cough, or clinically significant hypotension attributed to these agents.
22. Positive hepatitis C antibody test result at screening or within 3 months unless HCV RNA negative test is documented.
23. Diagnosis of anti-PLA2R negative MN or anti-PLA2R positive MN but Screening serum anti-PLA2R < 20 RU/mL or kidney disease other than PMN.
24. History of kidney transplant or planned kidney transplant or dialysis during the Treatment Period.
25. History of other solid organ (heart, lung, small bowel, pancreas, or liver) or bone marrow transplant; or planned transplant during the Treatment Period.
26. Splenectomy or functional asplenia.
27. Known or suspected complement deficiency, unless attributable to underlying disease.
28. Positive COVID-19 test at Screening. NOTE: At Screening, SARS‑CoV‑2 status must be confirmed by PCR. Participants with a PCR‑positive result for SARS‑CoV‑2 will be excluded from the study. Rescreening will be permitted once symptoms have resolved and a repeat SARS‑CoV‑2 test is negative, in accordance with local guidelines.
29. Participants with active or latent TB.
30. Hereditary (primary) hypogammaglobulinemia (as confirmed by medical history), including but not limited to X-linked agammaglobulinemia, CVID, or other diagnosed primary immunodeficiency disorders associated with significantly reduced immunoglobulin levels.
31. Participants with history of HIV who are not on anti-retroviral therapy or if on therapy have a known detectable viral load within 1 year of Screening.
32. Known medical or psychological condition(s), including substance abuse, or risk factor that, in the opinion of the Investigator, might interfere with the participant’s full participation in the study, pose any additional risk for the participant, or confound the assessment of the participant or outcome of the study.
33. History of any Neisseria infection.
34. History of unexplained, recurrent infection, or infection requiring treatment with systemic antibiotics within 90 days prior to Day 1.
35. Active systemic bacterial, viral, or fungal infection within 14 days prior to first dose of study intervention.
36. QTc > 480 msec in participants with bundle branch block.
37. Traditional Chinese medicines and Chinese proprietary medicines with systemic immunosuppressive properties including but not limited to Tripterygium Wilfordii or Tripterygium Wilfordii-containing medicines for the treatment of PMN within 6 months prior to Screening.
38. Participants with initiation or dose adjustment of SGLT2i within 12 weeks prior to randomization are excluded. Furthermore, the Investigators should not plan any new initiation or dose adjustment of SGLT2i during the 26‑week Blinded Treatment Period.
39. Use of MRA or ERA within 12 weeks prior to randomization and throughout the study period.

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 1

1. Change from Baseline in proteinuria based on 24-hour UPCR

Secondary endpoints 14

1. Change from Baseline in proteinuria based on 24-hour UPCR
2. Change from Baseline in proteinuria based on spot UPCR
3. Change from Baseline in serum albumin
4. Change from Baseline in anti-PLA2R antibody level
5. Change from Baseline in Peripheral CD19+ B cell count
6. Percentage of participants who achieve a CR
7. Percentage of participants who achieve a CR or PR
8. Change from Baseline for urine biomarkers
9. Incidence of TEAEs and TESAEs over time
10. Change from Baseline in safety parameters, vital signs, ECGs over time
11. Serum and urine ALXN1920 concentrations over time
12. Absolute values, change from Baseline, and percent change from Baseline in serum CAP activity and serum fH levels over time
13. ADA incidence, category of immune response, and titer through the duration of the study
14. Change from Baseline for urine biomarkers

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Placebo 1

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Alexion Pharmaceuticals Inc.

Sponsor organisation

Alexion Pharmaceuticals Inc.

Address

121 Seaport Boulevard

City

Boston

Postcode

02210-2050

Country

United States

Scientific contact point

Organisation

Alexion Pharmaceuticals Inc.

Contact name

European Clinical Trial Information

Public contact point

Organisation

Alexion Pharmaceuticals Inc.

Contact name

European Clinical Trial Information

Locations

3 EU/EEA countries · 9 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 50 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

4 submissions — initial application plus substantial / non-substantial modifications