MedPath

A Study to Evaluate the Efficacy and Safety of Efgartigimod PH20 Subcutaneous in Adult Patients With Primary Immune Thrombocytopenia

Phase 3
Completed
Conditions
Primary Immune Thrombocytopenia
Interventions
Biological: Efgartigimod PH20 SC
Other: Placebo PH20 SC
Registration Number
NCT04687072
Lead Sponsor
argenx
Brief Summary

This is a phase 3, multicenter, randomized, double-blinded, placebo-controlled, parallel-group trial to evaluate the efficacy, safety, and effect on QoL/PRO of efgartigimod PH20 SC treatment in adult patients with primary ITP.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
207
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Efgartigimod PH20 SCEfgartigimod PH20 SCPatients receiving efgartigimod PH20 SC treatment
Placebo PH20 SCPlacebo PH20 SCPatients receiving placebo PH20 SC treatment
Primary Outcome Measures
NameTimeMethod
Percentage of Participants With Chronic Immune Thrombocytopenia (ITP) With a Sustained Platelet Count Response Between Weeks 19 and 24Up to 6 weeks (between Weeks 19 and 24)

A participant was considered a responder for this endpoint (i.e., had a sustained platelet count response) if the participant had platelet counts of ≥50 × 10\^9/L for ≥4 of the 6 analysis visits between Weeks 19 and 24.

Secondary Outcome Measures
NameTimeMethod
Extent of Disease Control Over the 24-Week Treatment Period in the Chronic ITP PopulationUp to 24 weeks

Extent of disease control was defined as the number of cumulative weeks over the planned 24-week treatment period with platelet counts of ≥50×10\^9/L in the chronic ITP population.

Percentage of Participants in the Overall Population (Chronic and Persistent ITP) With a Sustained Platelet Count Response Between Weeks 19 and 24Up to 6 weeks (between Weeks 19 and 24)

A participant was considered a responder for this endpoint (i.e., had a sustained platelet count response) if the participant had platelet counts of ≥50 × 10\^9/L for ≥4 of the 6 analysis visits between Weeks 19 and 24.

Percentage of Participants in the Overall Population With Sustained Platelet Count Response Between Weeks 17 and 24Up to 8 weeks (between Weeks 17 and 24)

A participant was considered a responder for this endpoint (i.e., had a sustained platelet count response) if the participant had platelet counts of ≥50 × 10\^9/L for ≥6 of the 8 analysis visits between weeks 17 and 24.

Percentage of Participants in the Overall Population Achieving Overall Platelet Count Response at Any Time During the 24-week Treatment PeriodUp to 24 weeks

A participant was considered a responder for this endpoint (i.e., had an overall platelet count response) if the participant had platelet counts of ≥50 × 10\^9/L for ≥4 analysis visits at any time during the 24-week treatment period.

Extent of Disease Control Until Week 12 in the Overall PopulationUp to 12 weeks

Extent of disease control was defined as the number of cumulative weeks until Week 12 with platelet counts of ≥50×10\^9/L in the overall population.

Percentage of Participants in the Overall Population Achieving Overall Platelet Count Response at Any Time Until Week 12Up to 12 weeks

A participant was considered a responder for this endpoint (i.e., had an overall platelet count response) if the participant had platelet counts of ≥50 × 10\^9/L for ≥4 analysis visits at any time until Week 12.

Mean Change From Baseline in Platelet Count at Each Visit in the Overall PopulationBaseline and Weeks 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, Safety and Efficacy Follow-up Visit 1 (SEFU1) (up to Week 29), and SEFU2 (up to Week 33)

Change from Baseline at time point t = value at time point t - Baseline value. Baseline was defined as the last available value prior to first administration of the investigational medicinal product (IMP).

Time to Platelet Count Response in the Overall PopulationUp to 24 weeks

Time to platelet count response, defined as the time to have 2 consecutive platelet counts of ≥50 × 10\^9/L via Kaplan-Meier estimates.

Extent of Disease Control Over the 24-Week Treatment Period in the Overall PopulationUp to 24 weeks

Extent of disease control was defined as the number of cumulative weeks over the planned 24-week treatment period with platelet counts of ≥30×10\^9/L with at least ≥20×10\^9/L above Baseline in the overall population.

Extent of Disease Control Over the 24-Week Treatment Period in the Overall Population for Participants With Baseline Platelet Count of <15×10^9/LUp to 24 weeks

Extent of disease control was defined as the number of cumulative weeks over the planned 24-week treatment period with platelet counts of ≥30×10\^9/L with at least ≥20×10\^9/L above Baseline in the overall population.

Number of the World Health Organization (WHO)-Classified Bleeding Events (Grade ≥1) in the Overall PopulationUp to 24 weeks

Assessed using the WHO bleeding scale. The WHO bleeding scale is a five-point scale where Grade 0 = no bleeding; Grade 1 = petechial bleeding; Grade 2 = mild blood loss; Grade 3 = gross blood loss (requires transfusion); and Grade 4 = debilitating blood loss, associated with fatality.

Percentage of Participants With a Platelet Count International Working Group (IWG) ResponseUp to 24 weeks

IWG complete response was defined as platelet counts of ≥100 × 10\^9/L and the absence of bleeding events (WHO Grading = 0 \[no bleeding\]) for at least 2 separate, consecutive analysis visits at least 7 days apart.

IWG response was defined as platelet counts of ≥30 × 10\^9/L and a 2-fold increase of platelet count from Baseline and the absence of bleeding events (WHO grading = 0) for at least 2 separate, consecutive analysis visits that were at least 7 days apart.

Initial response was defined as platelet counts of ≥30 × 10\^9/L and a 2-fold increase from the Baseline platelet count at analysis visit 5.

Rate of Receipt of Rescue Therapy (Rescue Per Participant Per Month) in the Overall PopulationUp to 24 weeks

Rescue therapy was defined as an occurrence where the participant needed treatment with 1 or more rescue treatments. An occurrence was defined as a period of maximum 5 days where 1 or more rescue treatments were administered simultaneously or consecutively to the trial participant. The following rescue treatments were permitted: methylprednisolone, dexamethasone, prednisone, normal immunoglobulins, anti-D (Rho) immunoglobins, or platelet transfusions.

Percentage of Participants for Whom Dose and/or Frequency of Concurrent ITP Therapies Have Increased at Week 12 or Later in the Overall PopulationUp to 13 weeks (between Weeks 12 and 24)

A change in ITP therapy was defined as either an increase in the dose and/or frequency of a concurrent ITP therapy relative to Baseline or the initiation of a new concurrent ITP therapy.

Change From Baseline in Functional Assessment of Chronic Illness Therapy Fatigue Scale (FACIT-Fatigue) at Week 24 in the Overall PopulationBaseline and Week 24

The FACIT-fatigue scale is a short, 13-item, easy-to-administer tool that measures an individual's level of fatigue during his/her usual daily activities over the past week. The level of fatigue was measured by recording item responses on a 5-point Likert scale ranging from 0 "not at all" to 4 "very much". All items were summed to create a single fatigue score with a range from 0 to 52, where a higher FACIT-F score indicated more severe symptoms. A negative change score from Baseline indicated improvement in quality of life (QoL).

Change From Baseline in Functional Assessment of Cancer Therapy Questionnaire-Th6 (Fact-Th6) at Week 24 in the Overall PopulationBaseline and Weeks 4, 8, 12, 16, 20, and 24

The FACT-Th6 uses a 5-level Likert scale (0=not at all to 4=very much), with participants rating their degree of concern in the past 7 days. The 6 selected items pertain to ability to do usual activities, worry about problems with bleeding or bruising, worry about the possibility of serious bleeding, avoidance of physical or social activity because of concern with bleeding or bruising and frustration due to the inability to carry out usual activities. All items were summed to create a single score with a range from 0 to 24, where a higher score indicated less severe symptoms. A positive change score from Baseline indicated improvement in QoL.

Change From Baseline in Short Form-36 (SF-36) at Week 24 in the Overall PopulationBaseline and Week 24

The SF-36 is a 36-item scale constructed to survey health-related QoL on 8 domains: limitations in physical activities due to health problems; limitations in social activities due to physical or emotional problems; limitations in usual role activities due to physical health problems; bodily pain; general mental health (psychological distress and well-being); limitations in usual role activities due to emotional problems; vitality (energy and fatigue); and general health perceptions. The scores from the 8 domains were evaluated independently and aggregated into 2 norm-based summary component measures of physical and mental health. The summary component scores could range from 0 to 100, where a higher score indicated improvement in QoL. A positive change score from Baseline indicated improvement in QoL.

Incidence and Prevalence of Antibodies to Efgartigimod and/or rHuPH20 in the Overall PopulationUp to 35 weeks

Anti-drug antibody (ADA) incidence was defined as the percentage of participants with treatment-induced or treatment boosted ADA (denominator: number of evaluable participants). ADA prevalence was defined as the percentage of participants with treatment-unaffected ADA, treatment-induced ADA or treatment-boosted ADA (denominator: number of evaluable participants).

Titers of Antibodies to Efgartigimod and/or rHuPH20 in the Overall PopulationWeeks 3, 7, 11, 15, 19, 23, 24, SEFU1 (up to Week 29), and SEFU2 (up to Week 33)

A titer was determined in the samples with a positive assay response.

Incidence and Prevalence of Neutralizing Antibodies (NAb) to Efgartigimod and/or rHuPH20 in the Overall PopulationUp to 35 weeks

Samples were tested for the presence of NAb against efgartigimod and/or rHuPH20 and titers for NAb against rHuPH20.

NAb incidence is defined as the total percentage of participants with participant classification "baseline negative-postbaseline positive" and "baseline positive-postbaseline positive". NAb prevalence is defined as the total percentage of participants with participant classification "baseline negative-postbaseline positive," "baseline positive-postbaseline positive," or "baseline positive-postbaseline negative".

Serum Efgartigimod Trough Concentration (Ctrough) in the Overall PopulationPredose on Weeks 1, 2, 3, 17, 19, 21, 23, and 24

All pharmacokinetic (PK) samples were collected predose, on the day of IMP administration.

Percentage Change From Baseline in Total IgG in the Overall PopulationBaseline and Weeks 1, 2, 3, 17, 19, 21, 23, and 24

Samples were collected predose, on the day of IMP administration.

Number of Participants With Antiplatelet Antibodies in the Overall PopulationWeeks 7, 15, 23, and 24

The antiplatelet antibody was positive if optical density value \>0.129.

Trial Locations

Locations (200)

Investigator site 0010036

🇺🇸

Los Angeles, California, United States

Investigator site 0010040

🇺🇸

Columbus, Ohio, United States

Investigator Site 0010115

🇺🇸

Pittsburgh, Pennsylvania, United States

Investigator Site 0300009

🇬🇷

Thessaloníki, Greece

Investigator Site 9720013

🇮🇱

Ashkelon, Israel

Investigator Site 9720012

🇮🇱

Haifa, Israel

Investigator Site 9720008

🇮🇱

Jerusalem, Israel

Investigator Site 0520007

🇲🇽

Mexico, Mexico

Investigator Site 0400006

🇷🇴

Bucuresti, Romania

Investigator Site 0400016

🇷🇴

Cluj-Napoca, Romania

Investigator Site 0400007

🇷🇴

Craiova, Romania

Investigator Site 0070015

🇷🇺

Syktyvkar, Russian Federation

Investigator Site 3810008

🇷🇸

Kragujevac, Serbia

Investigator Site 9720011

🇮🇱

Jerusalem, Israel

Investigator Site 9720009

🇮🇱

Tel Aviv, Israel

Investigator Site 0860012

🇨🇳

Nanchang, China

Investigator Site 9950007

🇬🇪

Tbilisi, Georgia

Investigator Site 3530002

🇮🇪

Dublin, Ireland

Investigator Site 3530001

🇮🇪

Galway, Ireland

Investigator Site 0300008

🇬🇷

Athens, Greece

Investigator Site 0300010

🇬🇷

Athens, Greece

Investigator Site 9620002

🇯🇴

Amman, Jordan

Investigator Site 0810023

🇯🇵

Shimotsuke, Japan

Investigator Site 0480026

🇵🇱

Nowy Sącz, Poland

Investigator Site 0400009

🇷🇴

Bucuresti, Romania

Investigator Site 0660001

🇹🇭

Bangkok Noi, Thailand

Investigator Site 0660005

🇹🇭

Bangkok, Thailand

Investigator Site 2160006

🇹🇳

Sfax, Tunisia

Investigator Site 0900014

🇹🇷

Kocaeli, Turkey

Investigator Site 0900017

🇹🇷

Tekirdağ, Turkey

Investigator Site 0860009

🇨🇳

Kunming, China

Investigator Site 0860011

🇨🇳

Zhengzhou, China

Investigator Site 0010102

🇺🇸

Minneapolis, Minnesota, United States

Investigator Site 0610005

🇦🇺

Westmead, Australia

Investigator Site 0860014

🇨🇳

Shanxi, China

Investigator site 0010112

🇺🇸

Chicago, Illinois, United States

Investigator Site 0010104

🇺🇸

Weston, Florida, United States

Investigator Site 0610010

🇦🇺

Clayton, Australia

Investigator Site 3590017

🇧🇬

Plovdiv, Bulgaria

Investigator Site 0860055

🇨🇳

Huizhou, China

Investigator Site 9950006

🇬🇪

Tbilisi, Georgia

Investigator Site 0300007

🇬🇷

Patra, Greece

Investigator Site 0330009

🇫🇷

Créteil, France

Investigator site 0490008

🇩🇪

Essen, Germany

Investigator Site 0390037

🇮🇹

Alessandria, Italy

Investigator site 0390014

🇮🇹

Milan, Italy

Investigator Site 0330018

🇫🇷

Montpellier, France

Investigator Site 9950008

🇬🇪

Tbilisi, Georgia

Investigator Site 0390041

🇮🇹

Napoli, Italy

Investigator Site 0390015

🇮🇹

Novara, Italy

Investigator Site 0340007

🇪🇸

Barcelona, Spain

Investigator Site 9950019

🇬🇪

Tbilisi, Georgia

Investigator Site 3530003

🇮🇪

Dublin, Ireland

Investigator Site 0270003

🇿🇦

Johannesburg, South Africa

Investigator Site 0490012

🇩🇪

Gießen, Germany

Investigator Site 9720010

🇮🇱

Haifa, Israel

Investigator Site 0390011

🇮🇹

Reggio Calabria, Italy

Investigator Site 0390043

🇮🇹

Ferrara, Italy

Investigator Site 0390045

🇮🇹

Meldola, Italy

Investigator site 0390018

🇮🇹

Reggio Emilia, Italy

Investigator Site 0810054

🇯🇵

Kumamoto, Japan

Investigator Site 0810017

🇯🇵

Saitama, Japan

Investigator Site 0810052

🇯🇵

Tokyo, Japan

Investigator Site 0810048

🇯🇵

Tsukuba, Japan

Investigator Site 0810012

🇯🇵

Ōgaki, Japan

Investigator Site 0520004

🇲🇽

Chihuahua, Mexico

Investigator Site 0820008

🇰🇷

Seoul, Korea, Republic of

Investigator Site 0480037

🇵🇱

Skorzewo, Poland

Investigator Site 0480039

🇵🇱

Toruń, Poland

Investigator Site 3510006

🇵🇹

Braga, Portugal

Investigator Site 0470002

🇳🇴

Bergen, Norway

Investigator Site 0070038

🇷🇺

Nizhny Novgorod, Russian Federation

Investigator Site 0070039

🇷🇺

Smolensk, Russian Federation

Investigator Site 0640002

🇳🇿

Palmerston North, New Zealand

Investigator Site 0640005

🇳🇿

Christchurch, New Zealand

Investigator Site 0270005

🇿🇦

George, South Africa

Investigator Site 0340006

🇪🇸

Barcelona, Spain

Investigator Site 3510005

🇵🇹

Lisboa, Portugal

Investigator Site 3510001

🇵🇹

Porto, Portugal

Investigator Site 0400005

🇷🇴

Bucharest, Romania

Investigator Site 0400012

🇷🇴

Bucuresti, Romania

Investigator Site 0270004

🇿🇦

Observatory, South Africa

Investigator Site 3510007

🇵🇹

Lisboa, Portugal

Investigator Site 0070006

🇷🇺

Kaluga, Russian Federation

Investigator Site 3810006

🇷🇸

Belgrade, Serbia

Investigator Site 0340037

🇪🇸

Madrid, Spain

Investigator site 0340013

🇪🇸

Sevilla, Spain

Investigator Site 0270001

🇿🇦

Pretoria, South Africa

Investigator Site 0340023

🇪🇸

Barcelona, Spain

Investigator Site 0070012

🇷🇺

Tula, Russian Federation

Investigator Site 0340024

🇪🇸

Alava, Spain

Investigator Site 0340036

🇪🇸

Sabadell, Spain

Investigator Site 0270002

🇿🇦

Randburg, South Africa

Investigator Site 8860001

🇨🇳

New Taipei City, Taiwan

Investigator Site 0900003

🇹🇷

Ankara, Turkey

Investigator Site 0660008

🇹🇭

Bangkok, Thailand

Investigator Site 0660009

🇹🇭

Khon Kaen, Thailand

Investigator Site 0900006

🇹🇷

Ankara, Turkey

Investigator Site 0900016

🇹🇷

Edirne, Turkey

Investigator Site 0900004

🇹🇷

İzmir, Turkey

Investigator Site 8860003

🇨🇳

Taoyuan, Taiwan

Investigator Site 0660002

🇹🇭

Bangkok, Thailand

Investigator Site 0900007

🇹🇷

Adapazarı, Turkey

Investigator Site 0660003

🇹🇭

Bangkok, Thailand

Investigator Site 0660006

🇹🇭

Pathum Thani, Thailand

Investigator Site 2160001

🇹🇳

Sousse, Tunisia

Investigator Site 0900019

🇹🇷

Trabzon, Turkey

Investigator Site 2160002

🇹🇳

Tunis, Tunisia

Investigator Site 0900015

🇹🇷

Ankara, Turkey

Investigator Site 0900018

🇹🇷

Malatya, Turkey

Investigator Site 0900009

🇹🇷

Samsun, Turkey

Investigator Site 0900008

🇹🇷

Ankara, Turkey

Investigator Site 0900013

🇹🇷

Istanbul, Turkey

Investigator Site 0900010

🇹🇷

Mersin, Turkey

Investigator site 0440011

🇬🇧

Bradford, United Kingdom

Investigator Site 0440005

🇬🇧

Coventry, United Kingdom

Investigator Site 0440008

🇬🇧

London, United Kingdom

Investigator Site 0440041

🇬🇧

London, United Kingdom

Investigator Site 0440014

🇬🇧

Truro, United Kingdom

Investigator Site 0340022

🇪🇸

Murcia, Spain

Investigator Site 0340004

🇪🇸

Valencia, Spain

Investigator Site 0010116

🇺🇸

Springdale, Arkansas, United States

Investigator Site 3590015

🇧🇬

Sofia, Bulgaria

Investigator Site 0610001

🇦🇺

Hobart, Australia

Investigator site 0010193

🇺🇸

Chicago, Illinois, United States

Investigator Site 0010062

🇺🇸

Fort Wayne, Indiana, United States

Investigator site 0010042

🇺🇸

Iowa City, Iowa, United States

Investigator Site 0010079

🇺🇸

Lisle, Illinois, United States

Investigator Site 0010083

🇺🇸

Detroit, Michigan, United States

Investigator Site 0010095

🇺🇸

Oklahoma City, Oklahoma, United States

Investigator Site 0540001

🇦🇷

Buenos Aires, Argentina

Investigator Site 0540003

🇦🇷

Córdoba, Argentina

Investigator Site 0610002

🇦🇺

Box Hill, Australia

Investigator Site 0540004

🇦🇷

Buenos Aires, Argentina

Investigator Site 0610009

🇦🇺

Adelaide, Australia

Investigator Site 0610004

🇦🇺

Bedford Park, Australia

Investigator Site 0610012

🇦🇺

Garran, Australia

Investigator Site 0610003

🇦🇺

West Perth, Australia

Investigator Site 0610011

🇦🇺

Perth, Australia

Investigator Site 0560003

🇨🇱

Viña Del Mar, Chile

Investigator Site 0860003

🇨🇳

Beijing, China

Investigator Site 0860013

🇨🇳

Beijing, China

Investigator Site 0560002

🇨🇱

Santiago, Chile

Investigator Site 0560004

🇨🇱

Temuco, Chile

Investigator Site 0860008

🇨🇳

Bengbu, China

Investigator Site 0860015

🇨🇳

Shenzhen, China

Investigator Site 0860010

🇨🇳

Wuhan, China

Investigator Site 0860001

🇨🇳

Tianjin, China

Investigator Site 0860006

🇨🇳

Wenzhou, China

Investigator Site 0860005

🇨🇳

Zhejiang, China

Investigator Site 0450005

🇩🇰

Roskilde, Denmark

Investigator Site 0860058

🇨🇳

Zhenjiang, China

Investigator Site 0860002

🇨🇳

Wuxi, China

Investigator site 0860062

🇨🇳

Zhenjiang, China

Investigator Site 9720007

🇮🇱

Petach Tikva, Israel

Investigator Site 0390032

🇮🇹

Milan, Italy

Investigator Site 0390044

🇮🇹

Napoli, Italy

Investigator Site 0390035

🇮🇹

Potenza, Italy

Investigator Site 0390046

🇮🇹

Rome, Italy

Investigator Site 0390033

🇮🇹

Terni, Italy

Investigator Site 0390036

🇮🇹

Varese, Italy

Investigator Site 0810056

🇯🇵

Chiba, Japan

Investigator Site 0810015

🇯🇵

Hirakata, Japan

Investigator Site 0810010

🇯🇵

Hiroshima, Japan

Investigator Site 0810053

🇯🇵

Kanagawa, Japan

Investigator Site 0810051

🇯🇵

Kitakyushu, Japan

Investigator Site 0810018

🇯🇵

Maebashi, Japan

Investigator Site 0810057

🇯🇵

Morioka, Japan

Investigator Site 0810016

🇯🇵

Shibukawa, Japan

Investigator Site 0810044

🇯🇵

Yamanashi, Japan

Investigator Site 0810039

🇯🇵

Shinagawa-Ku, Japan

Investigator Site 9620001

🇯🇴

Irbid, Jordan

Investigator Site 0820005

🇰🇷

Seongnam, Korea, Republic of

Investigator Site 0810038

🇯🇵

Tama, Japan

Investigator Site 0820003

🇰🇷

Seoul, Korea, Republic of

Investigator Site 0820006

🇰🇷

Seoul, Korea, Republic of

Investigator Site 0820004

🇰🇷

Seoul, Korea, Republic of

Investigator Site 0820007

🇰🇷

Seoul, Korea, Republic of

Investigator Site 0520002

🇲🇽

Aguascalientes, Mexico

Investigator Site 0520003

🇲🇽

Monterrey, Mexico

Investigator Site 0520001

🇲🇽

Oaxaca, Mexico

Investigator Site 0480013

🇵🇱

Katowice, Poland

Investigator Site 0640001

🇳🇿

Auckland, New Zealand

Investigator Site 0470003

🇳🇴

Oslo, Norway

Investigator Site 0480014

🇵🇱

Lublin, Poland

Investigator Site 0480033

🇵🇱

Warszawa, Poland

Investigator Site 3510003

🇵🇹

Coimbra, Portugal

Investigator Site 3510002

🇵🇹

Lisboa, Portugal

Investigator Site 3510004

🇵🇹

Porto, Portugal

Investigator Site 0400011

🇷🇴

Sibiu, Romania

Investigator Site 0400008

🇷🇴

Târgu-Mureş, Romania

Investigator Site 0070040

🇷🇺

Kirov, Russian Federation

Investigator Site 0010045

🇺🇸

Washington, District of Columbia, United States

Investigator Site 9950009

🇬🇪

Tbilisi, Georgia

Investigator Site 9950011

🇬🇪

Tbilisi, Georgia

Investigator Site 0070037

🇷🇺

Novosibirsk, Russian Federation

Investigator Site 0070024

🇷🇺

Pyatigorsk, Russian Federation

Investigator Site 0070025

🇷🇺

Saint Petersburg, Russian Federation

Investigator Site 0070026

🇷🇺

Moscow, Russian Federation

Investigator Site 0660004

🇹🇭

Chiang Mai, Thailand

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