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Paroxysmal Nocturnal HemoglobinuriaPhase 3ACCESS-EXTNCT05744921

A Study in Adult Patients With Paroxysmal Nocturnal Hemoglobinuria (PNH) to Evaluate How Safe Long-term Treatment With Pozelimab + Cemdisiran Combination Therapy is and How Well it Works

A Phase 3 study testing Pozelimab and Cemdisiran in people with Paroxysmal Nocturnal Hemoglobinuria, run by Regeneron Pharmaceuticals at 50 sites in 21 countries.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
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Trial summary

This study is researching an experimental treatment combination with two experimental drugs called pozelimab and cemdisiran. The study is focused on people with paroxysmal nocturnal hemoglobinuria (PNH). Read more about this study

Who is it for?
Ages 18 years and older
Conditions the study is for
Paroxysmal Nocturnal Hemoglobinuria
What is being tested?
Pozelimab and Cemdisiran
Type of treatment
Injection or infusion
Could I receive a placebo?
No, everyone receives an active treatment
How many people
202 participants
Where
50 sitesin 21 countries
Study dates
7 Mar 2023to 10 Oct 2028
Phase
Phase 3
Are there results?
Not yet: the study is under way

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

  • Patients Entering from the Parent Study
  • Patients with PNH who have completed, without permanent discontinuation, study treatment in the parent study (R3918-PNH-2021[NCT05133531]), including the post-Open-label treatment period (OLTP) transition period, if applicable.
  • Willing and able to comply with clinic visits and study-related procedures, including meningococcal vaccinations required per protocol.
  • Patients Entering with C5 polymorphism
  • Patients with PNH who have a documented C5 polymorphism rendering them refractory to eculizumab or ravulizumab (eg, p.Arg885His, p.Arg885Cys), as described in the protocol
  • Diagnosis of PNH confirmed by high-sensitivity flow cytometry testing with PNH granulocytes or monocytes
Show all 9Show fewer
  • Active disease, as defined by the presence of 1 or more PNH-related sign or symptom as described in the protocol
  • LDH level ≥2 × upper limit of normal (ULN) at the screening visit
  • Willing and able to comply with clinic visits and study-related procedures, including meningococcal vaccinations required per protocol

Who cannot join

  • Patients Entering from the Parent Study
  • Significant protocol deviation(s) in the parent study based on the investigator's judgment and to the extent that these would (if continued) impact the study objectives and/or safety of the patient
  • Any new condition or worsening of an existing condition which, in the opinion of the investigator, would make the patient unsuitable for enrollment or could interfere with the patient participating in or completing the study
  • Patients Entering with C5 polymorphism
  • Prior treatment with complement inhibitors within 5 half-lives of the respective agent prior to screening, except for prior eculizumab or ravulizumab which are not exclusionary
  • Receipt of an organ transplant, history of bone marrow transplantation or other hematologic transplant
Show all 13Show fewer
  • Not meeting meningococcal vaccination requirements and, at a minimum, documentation of quadrivalent meningococcal vaccination within 5 years prior to enrollment and serotype B vaccine within 3 years prior to enrollment as described in the protocol
  • Positive hepatitis B surface antigen or hepatitis C virus Ribonucleic acid (RNA) during screening
  • Patients with known HIV with history of opportunistic infections in the last 1 year as described in the protocol
  • Known hereditary complement deficiency
  • Documented history of active, uncontrolled, ongoing systemic autoimmune diseases
  • Documented history of liver cirrhosis or patients with liver disease with evidence of current impaired liver function or patients with elevations in Alanine aminotransferase (ALT) or Aspartate aminotransferase (AST) (unrelated to PNH or its complications) as described in the protocol
  • Note: Other protocol-defined Inclusion/ Exclusion Criteria apply

Trial locations and contacts

50 sites in 21 countries. Contact the study team or a site near you to ask about taking part.

Clinical Trials Administrator contact

844-734-6643

clinicaltrials@regeneron.com

50 sites in 21 countries

South Korea8 sites, 8 recruiting

  • Pusan National University Hospital

    Busan, 49241

    Recruiting

  • Gachon University Gil Medical Center

    Incheon, Namdong-Gu, 21565

    Recruiting

  • Severance Hospital Yonsei University Health System

    Seoul, 03722

    Recruiting

  • Samsung Medical Center

    Seoul, 06351

    Recruiting

  • The Catholic University of Korea, Seoul St. Mary's Hospital

    Seoul, 06591

    Recruiting

  • Ewha Womans University Mokdong Hospital

    Seoul, 07985

    Recruiting

  • St. Vincent Hospital

    Suwon, Gyeonggi-do, 16247

    Recruiting

  • Ajou University Medical Center

    Suwon, Gyeonggi-do, 16499

    Recruiting

Other trials in South Korea

Taiwan7 sites, 7 recruiting

  • Changhua Christian Hospital

    Changhua, 500

    Recruiting

  • Hualien Tzu Chi Hospital

    Hualien City, 97002

    Recruiting

  • China Medical University Hospital

    Taichung, Central Taiwan, 40447

    Recruiting

  • Taichung Veterans General Hospital (VGHTC)

    Taichung, 4070

    Recruiting

  • National Taiwan University Hospital

    Taipei, 10002

    Recruiting

  • Tri-Service General Hospital

    Taipei, 11490

    Recruiting

  • Chang Gung Memorial Hospital - Linkou Branch

    Taoyuan, Hunan Province, 33305

    Recruiting

Other trials in Taiwan

India5 sites, 5 recruiting

  • Postgraduate Institute of Medical Education & Research

    Chandigarh, 160012

    Recruiting

  • Bhagwan Mahaveer Cancer Hospital and Research Centre (BMCHRC)

    Jaipur, 302017

    Recruiting

  • Amrita Institute of Medical Sciences (AIMS) and Research Centre Aims

    Kochi, Kerala, 682041

    Recruiting

  • K J Somaiya Super Specialty Hospital & Research Centre

    Mumbai, Maharashtra, 400022

    Recruiting

  • Rajiv Gandhi Cancer Institute & Research Center (RGCIRC) - Rohini Campus

    New Delhi, National Capital Territory of Delhi, 110085

    Recruiting

Other trials in India

Thailand4 sites, 4 recruiting

  • King Chulalongkorn Memorial Hospital

    Bangkok, 10330

    Recruiting

  • Chiang Mai University

    Chiang Mai, 50200

    Recruiting

  • Prince Of Songkla Hospital, Prince Of Songkhla University

    Hat Yai, Changwat Songkhla, 90110

    Recruiting

  • Faculty of Medicine Khon Kaen University

    Khon Kaen, 40002

    Recruiting

Other trials in Thailand

Malaysia3 sites, 3 recruiting

  • Hospital Ampang

    Ampang, Selangor, 68000

    Recruiting

  • Hospital Queen Elizabeth

    Kota Kinabalu, Sabah, 88200

    Recruiting

  • Hospital Tg Ampuan Afzan

    Kuantan, Pahang, 25200

    Recruiting

Other trials in Malaysia

Poland3 sites, 2 recruiting

  • In-Vivo Sp. z o.o.

    Bydgoszcz, Kuyavian-Pomeranian Voivodeship, 85-048

    Recruiting

  • Szpital Uniwersytecki Nr2 Bydgoszcz

    Bydgoszcz, 85-168

    Completed

  • University Clinical Center Medical University of Gdansk

    Gdansk, Pomeranian Voivodeship, 80-214

    Recruiting

Other trials in Poland

Brazil2 sites, 2 recruiting

  • Liga Paranaense de Combate Ao Cancer - Hospital Erasto Gaertner

    Curitiba, Jardim Santo Andre, 09090-790

    Recruiting

  • A Beneficencia Portuguesa de Sao Paulo, BP Mirante

    São Paulo, 01321-001

    Recruiting

Other trials in Brazil

Italy2 sites, 2 recruiting

  • Aou Careggi

    Florence, Firenze, 50139

    Recruiting

  • SC Hematology, AOU Città della Salute e della Scienza di Torino

    Torino, 10126

    Recruiting

Other trials in Italy

Japan2 sites, 1 recruiting

  • Japanese Red Cross Aichi Medical Center Nagoya Daini Hospital

    Nagoya, Aichi-ken, 466-8650

    Withdrawn

  • University of Tsukuba Hospital

    Tsukuba, Ibaraki, 305-8576

    Recruiting

Other trials in Japan

Spain2 sites, 2 recruiting

  • Hospital Clinic de Barcelona

    Barcelona, 08036

    Recruiting

  • Hospital Universitario Basurto

    Bilbao, Vizcaya, 48013

    Recruiting

Other trials in Spain

Turkey (Türkiye)2 sites, 2 recruiting

  • Ege University Faculty of Medicine

    Bornova, İzmir, 35100

    Recruiting

  • Istanbul University

    Istanbul, 34418

    Recruiting

Other trials in Turkey (Türkiye)

Canada1 site, 1 recruiting

  • Toronto General Hospital

    Toronto, Ontario, M5G 2C4

    Recruiting

Other trials in Canada

Colombia1 site, 1 recruiting

  • Hospital Pablo Tobon Uribe

    Medellín, Antioquia, 050034

    Recruiting

Other trials in Colombia

Hungary1 site, 1 recruiting

  • Semmelweis University/Semmelweis Egyetem

    Budapest, 1083

    Recruiting

Other trials in Hungary

Jordan1 site, 1 recruiting

  • Jordan University Hospital (JUH)

    Amman, 11942

    Recruiting

Other trials in Jordan

Mexico1 site, 1 recruiting

  • Servicio de Hematologia del Hospital Universitario de la UANL

    Monterrey, Nuevo León, 64460

    Recruiting

Other trials in Mexico

Peru1 site, 1 recruiting

  • Clinica San Felipe

    Lima, 15072

    Recruiting

Other trials in Peru

Philippines1 site, 1 recruiting

  • St Lukes Medical Center

    Quezon City, National Capital Region, 1634

    Recruiting

Other trials in Philippines

Romania1 site, 1 recruiting

  • Prof Dr Ion Chiricuta Cancer Institute

    Cluj-Napoca, Cluj, 400015

    Recruiting

Other trials in Romania

Singapore1 site, 1 recruiting

  • National University Hospital

    Singapore, 119074

    Recruiting

Other trials in Singapore

United Kingdom1 site, 1 recruiting

  • Leeds Teaching Hospitals NHS Trust - St. James Institute of Oncology

    Leeds, LS97TF

    Recruiting

Other trials in United Kingdom

About this study

Official title: An Open-Label Extension Study to Evaluate the Long-Term Safety, Tolerability, and Efficacy of Pozelimab and Cemdisiran Combination Therapy in Patients With Paroxysmal Nocturnal Hemoglobinuria

This study is researching an experimental treatment combination with two experimental drugs called pozelimab and cemdisiran. The study is focused on people with paroxysmal nocturnal hemoglobinuria (PNH). The aim of this study is to see how safe and effective the pozelimab + cemdisiran combination is for people with PNH in the long term. The pozelimab + cemdisiran combination may be referred to as "study drugs" in this section.

This study is looking at several other research questions, including:

  • How effective is the pozelimab + cemdisiran combination?
  • What side effects may happen from taking the study drugs?
  • How much of each study drug is in the blood at different times?
  • Whether the body makes antibodies against the study drugs (which could make the drugs less effective or could lead to side effects)
Being tested
Pozelimab, Cemdisiran
Keywords
PNH
Medical subject headings
Hemoglobinuria, Paroxysmal

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • PozelimabDrug

    Also called REGN3918

    Administered per the protocol

  • CemdisiranDrug

    Also called ALN-CC5

    Administered per the protocol

Study groups in NCT05744921
Study groupRoleWhat they receive
PNH Transition PatientsExperimentalPatients with PNH who completed treatment/ protocol requirements (as applicable) in the parent study (R3918-PNH-2021 [NCT05133531])
Receives: Drug: Pozelimab; Drug: Cemdisiran
C5 Polymorphism PatientsExperimentalPatients who have not been treated in either parent study but who have a documented complement component 5 (C5) variation rendering them refractory to eculizumab/ravulizumab. Note: Loading dose of pozelimab administered IV on Day 1.
Receives: Drug: Pozelimab; Drug: Cemdisiran

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Incidence of treatment-emergent serious adverse events (SAEs)

    An SAE is any untoward medical occurrence that at any dose:

    • Results in death
    • Is life-threatening
    • Requires in-patient hospitalization or prolongation of existing hospitalization.
    • Results in persistent or significant disability/incapacity
    • Is a congenital anomaly/birth defect.
    • Is an important medical event

    Measured: Up to week 108

  2. Severity of treatment-emergent SAEs

    Measured: Up to week 108

  3. Incidence of treatment emergent adverse events of special interest (AESIs)

    An AESI (serious or non-serious) is one of scientific and medical concern specific to the sponsor's product or program, for which ongoing monitoring and rapid communication by the Investigator to the sponsor can be appropriate. Such an event might warrant further investigation in order to characterize and understand it

    Measured: Up to week 108

  4. Severity of treatment emergent AESIs

    Measured: Up to week 108

  5. Incidence of adverse events (AEs) leading to permanent treatment discontinuation

    Any untoward medical occurrence in a patient administered a study drug which may or may not have a causal relationship with the study drug.

    Measured: Up to week 108

  6. Severity of adverse events (AEs) leading to permanent treatment discontinuation

    Any untoward medical occurrence in a patient administered a study drug which may or may not have a causal relationship with the study drug.

    Measured: Up to week 108

  7. Percent change from baseline in lactate dehydrogenase (LDH)

    Measured: Baseline to week 36

Secondary outcomes (53)

  1. Adequate control of hemolysis (LDH ≤1.5 × ULN)

    Measured: Post-baseline through week 108

  2. Transfusion avoidance

    Not requiring red blood cell (RBC) transfusion as per protocol algorithm based on hemoglobin values

    Measured: Post-baseline through week 36

  3. Transfusion avoidance

    Not requiring red blood cell (RBC) transfusion as per protocol algorithm based on hemoglobin values

    Measured: Post-baseline through week 48

  4. Transfusion avoidance

    Not requiring red blood cell (RBC) transfusion as per protocol algorithm based on hemoglobin values

    Measured: Post-baseline through week 76

  5. Transfusion avoidance

    Not requiring red blood cell (RBC) transfusion as per protocol algorithm based on hemoglobin values

    Measured: Post-baseline through week 108

  6. Breakthrough hemolysis (defined as LDH ≥2 × ULN [subsequent to initial achievement of LDH ≤1.5 × ULN] concomitant with signs or symptoms associated with hemolysis)

    Measured: Post-baseline through week 36

  7. Breakthrough hemolysis (defined as LDH ≥2 × ULN [subsequent to initial achievement of LDH ≤1.5 × ULN] concomitant with signs or symptoms associated with hemolysis)

    Measured: Post-baseline through week 48

  8. Breakthrough hemolysis (defined as LDH ≥2 × ULN [subsequent to initial achievement of LDH ≤1.5 × ULN] concomitant with signs or symptoms associated with hemolysis)

    Measured: Post-baseline through week 76

  9. Breakthrough hemolysis (defined as LDH ≥2 × ULN [subsequent to initial achievement of LDH ≤1.5 × ULN] concomitant with signs or symptoms associated with hemolysis)

    Measured: Post-baseline through week 108

  10. Hemoglobin stabilization

    Patients who do not receive an RBC transfusion and have no decrease in hemoglobin level of ≥2 g/dL

    Measured: Post-baseline through week 36

  11. Hemoglobin stabilization

    Patients who do not receive an RBC transfusion and have no decrease in hemoglobin level of ≥2 g/dL

    Measured: Post-baseline through week 48

  12. Hemoglobin stabilization

    Patients who do not receive an RBC transfusion and have no decrease in hemoglobin level of ≥2 g/dL

    Measured: Post-baseline through week 76

  13. Hemoglobin stabilization

    Patients who do not receive an RBC transfusion and have no decrease in hemoglobin level of ≥2 g/dL

    Measured: Post-baseline through week 108

  14. Percent change in LDH

    Measured: From baseline to week 48

  15. Percent change in LDH

    Measured: From baseline to week 76

  16. Percent change in LDH

    Measured: From baseline to week 108

  17. Change in fatigue

    Measured by the FACIT-Fatigue scale The FACIT-F is a 13-item, self-reported PRO measure assessing an individual's level of fatigue during their usual daily activities over the past week. This questionnaire is part of the FACIT measurement system, a compilation of questions measuring health-related QoL in patients with cancer and other chronic illnesses. The FACIT-fatigue assesses the level of fatigue using a 5-point Likert scale ranging from 0 (not at all) to 4 (very much). Scores range from 0 to 52, with higher scores indicating greater fatigue.

    Measured: From baseline to week 36

  18. Change in fatigue

    Measured by the FACIT-Fatigue scale The FACIT-F is a 13-item, self-reported PRO measure assessing an individual's level of fatigue during their usual daily activities over the past week. This questionnaire is part of the FACIT measurement system, a compilation of questions measuring health-related QoL in patients with cancer and other chronic illnesses. The FACIT-fatigue assesses the level of fatigue using a 4-point Likert scale ranging from 0 (not at all) to 4 (very much). Scores range from 0 to 52, with higher scores indicating greater fatigue.

    Measured: From baseline to week 48

  19. Change in fatigue

    Measured by the FACIT-Fatigue scale The FACIT-F is a 13-item, self-reported PRO measure assessing an individual's level of fatigue during their usual daily activities over the past week. This questionnaire is part of the FACIT measurement system, a compilation of questions measuring health-related QoL in patients with cancer and other chronic illnesses. The FACIT-fatigue assesses the level of fatigue using a 4-point Likert scale ranging from 0 (not at all) to 4 (very much). Scores range from 0 to 52, with higher scores indicating greater fatigue.

    Measured: From baseline to week 76

  20. Change in fatigue

    Measured by the FACIT-Fatigue scale The FACIT-F is a 13-item, self-reported PRO measure assessing an individual's level of fatigue during their usual daily activities over the past week. This questionnaire is part of the FACIT measurement system, a compilation of questions measuring health-related QoL in patients with cancer and other chronic illnesses. The FACIT-fatigue assesses the level of fatigue using a 4-point Likert scale ranging from 0 (not at all) to 4 (very much). Scores range from 0 to 52, with higher scores indicating greater fatigue.

    Measured: From baseline to weeks 108

  21. Change in physical function (PF) scores on the EORTC QLQ-C30

    EORTC QLQ-C30 (European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire)

    EORTC-QLQ-C30 is a 30-item subject self-report questionnaire composed of both multi-item and single scales, including a global health status/quality of life (GHS/QoL) scale. Participants rate items on a four-point scale, with 1 as "not at all" and 4 as "very much." A change of 5 - 10 points is considered a small change. A change of 10 - 20 points is considered a moderate change.

    Measured: From baseline to week 36

  22. Change in PF scores on the EORTC QLQ-C30

    EORTC QLQ-C30 (European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire)

    EORTC-QLQ-C30 is a 30-item subject self-report questionnaire composed of both multi-item and single scales, including a global health status/quality of life (GHS/QoL) scale. Participants rate items on a four-point scale, with 1 as "not at all" and 4 as "very much." A change of 5 - 10 points is considered a small change. A change of 10 - 20 points is considered a moderate change.

    Measured: From baseline to week 48

  23. Change in PF scores on the EORTC QLQ-C30

    EORTC QLQ-C30 (European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire)

    EORTC-QLQ-C30 is a 30-item subject self-report questionnaire composed of both multi-item and single scales, including a global health status/quality of life (GHS/QoL) scale. Participants rate items on a four-point scale, with 1 as "not at all" and 4 as "very much." A change of 5 - 10 points is considered a small change. A change of 10 - 20 points is considered a moderate change.

    Measured: From baseline to week 76

  24. Change in PF scores on the EORTC QLQ-C30

    EORTC QLQ-C30 (European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire)

    EORTC-QLQ-C30 is a 30-item subject self-report questionnaire composed of both multi-item and single scales, including a global health status/quality of life (GHS/QoL) scale. Participants rate items on a four-point scale, with 1 as "not at all" and 4 as "very much." A change of 5 - 10 points is considered a small change. A change of 10 - 20 points is considered a moderate change.

    Measured: From baseline to week 108

  25. Change in GHS/quality of life (QOL) scale on the EORTC QLQ-C30

    GHS/QoL (Global Health Status/ Quality of Life)

    Global Health Status/Quality of Life (GHS/Qol) Score (Items 29 and 30) Using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30). Participants rate items on a four-point scale, with 1 as "not at all" and 4 as "very much." A change of 5 - 10 points is considered a small change. A change of 10 - 20 points is considered a moderate change.

    Measured: From baseline to week 36

  26. Change in GHS/quality of life (QOL) scale on the EORTC QLQ-C30

    GHS/QoL (Global Health Status/ Quality of Life)

    Global Health Status/Quality of Life (GHS/Qol) Score (Items 29 and 30) Using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30). Participants rate items on a four-point scale, with 1 as "not at all" and 4 as "very much." A change of 5 - 10 points is considered a small change. A change of 10 - 20 points is considered a moderate change.

    Measured: From baseline to week 48

  27. Change in GHS/quality of life (QOL) scale on the EORTC QLQ-C30

    GHS/QoL (Global Health Status/ Quality of Life)

    Global Health Status/Quality of Life (GHS/Qol) Score (Items 29 and 30) Using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30). Participants rate items on a four-point scale, with 1 as "not at all" and 4 as "very much." A change of 5 - 10 points is considered a small change. A change of 10 - 20 points is considered a moderate change.

    Measured: From baseline to week 76

  28. Change in GHS/quality of life (QOL) scale on the EORTC QLQ-C30

    GHS/QoL (Global Health Status/ Quality of Life)

    Global Health Status/Quality of Life (GHS/Qol) Score (Items 29 and 30) Using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30). Participants rate items on a four-point scale, with 1 as "not at all" and 4 as "very much." A change of 5 - 10 points is considered a small change. A change of 10 - 20 points is considered a moderate change.

    Measured: From baseline to week 108

  29. Normalization of LDH

    Measured: From post-baseline through week 108

  30. Rate of red blood cell (RBC) transfusion

    Per protocol algorithm

    Measured: Post-baseline through week 36

  31. Rate of RBC transfusion

    Per protocol algorithm

    Measured: Post-baseline through week 48

  32. Rate of RBC transfusion

    Per protocol algorithm

    Measured: Post-baseline through week 76

  33. Rate of RBC transfusion

    Per protocol algorithm

    Measured: Post-baseline through week 108

  34. Number of units of RBC transfusion

    Per protocol algorithm

    Measured: Post-baseline through week 36

  35. Number of units of RBC transfusion

    Per protocol algorithm

    Measured: Post-baseline through week 48

  36. Number of units of RBC transfusion

    Per protocol algorithm

    Measured: Post-baseline through week 76

  37. Number of units of RBC transfusion

    Per protocol algorithm

    Measured: Post-baseline through week 108

  38. Percentage of days with LDH ≤1.5x upper limit of normal (ULN)

    Measured: Post-baseline through week 36

  39. Percentage of days with LDH ≤1.5x ULN

    Measured: Post-baseline through week 48

  40. Percentage of days with LDH ≤1.5x ULN

    Measured: Post-baseline through week 76

  41. Percentage of days with LDH ≤1.5x ULN

    Measured: Post-baseline through week 108

  42. Change in hemoglobin levels

    Measured: From baseline to week 36

  43. Change in hemoglobin levels

    Measured: From baseline to week 48

  44. Change in hemoglobin levels

    Measured: From baseline to week 76

  45. Change in hemoglobin levels

    Measured: From baseline to week 108

  46. Change in total complement hemolytic activity assay (CH50)

    Measured: Through week 108

  47. Percent change in CH50

    Measured: Through week 108

  48. Concentrations of total pozelimab in serum

    Measured: Through week 108

  49. Concentrations of cemdisiran in plasma

    Measured: Through week 24

  50. Incidence of treatment-emergent anti-drug antibodies to pozelimab

    Measured: Through week 108

  51. Incidence of treatment-emergent anti-drug antibodies to cemdisiran

    Measured: Through week 108

  52. Concentration of total complement component 5 (C5) in plasma

    Measured: Through week 108

  53. Percent change of concentration of total C5 in plasma

    Measured: Through week 108

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted27 Feb 2023
  2. Study start7 Mar 2023
  3. Primary completion10 Oct 2028 (estimated)
  4. Study completion10 Oct 2028 (estimated)

Resources

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 3
Primary purpose
Treatment
Allocation
Non-randomised
Intervention model
Parallel groups
Masking
None (open label)
Enrolment
202 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT05744921
Sponsor's protocol ID
R3918-PNH-2050
Other IDs
2021-004931-10, 2023-510336-36-00, 2023
Acronym
ACCESS-EXT
Status last verified
Nov 2026
First submitted
6 Feb 2023
Last updated
5 Nov 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
Individual data sharing
Yes: All Individual Patient Data (IPD) that underlie publicly available results will be considered for sharing

Questions about this trial

What is this clinical trial studying?

A Phase 3 study testing Pozelimab and Cemdisiran in people with Paroxysmal Nocturnal Hemoglobinuria, run by Regeneron Pharmaceuticals at 50 sites in 21 countries.

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 9 inclusion and 13 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: looking for participants now, as of the sponsor's last update on 5 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 50 sites in South Korea, Taiwan, India, Thailand, Malaysia and 16 more countries. 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 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact Clinical Trials Administrator (844-734-6643, clinicaltrials@regeneron.com), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Incidence of treatment-emergent serious adverse events (SAEs) (time frame: Up to week 108). The study lists 7 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05744921.

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 5 Nov 2026.

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