Trial Outcomes & Findings for A Phase 3 Study to Evaluate the Long-term Safety, Tolerability and Efficacy of Efgartigimod PH20 SC in Adult Participants With Bullous Pemphigoid (NCT NCT05681481)
NCT ID: NCT05681481
Last Updated: 2026-02-25
Results Overview
Adverse events, Serious Adverse event and Adverse events of special interest. Adverse events in the 'Infections and infestations' SOC were defined as AESIs because efgartigimod causes a transient reduction in total IgG levels.
TERMINATED
PHASE3
64 participants
Up to 56 weeks
2026-02-25
Participant Flow
This study was conducted at 38 sites that enrolled participants in 17 countries. On 13 Jan 2025 the sponsor terminated the study early due to a lack of efficacy of efgartigimod when administered with concomitant OCS in the antecedent study (ARGX-113-2009).
The study enrolled participants with bullous pemphigoid (BP) who completed the week-36/end-of-treatment period (EoTP) visit in ARGX-113-2009. A total of 64 participants (of 98 eligible participants) rolled over from ARGX-113-2009.
Participant milestones
| Measure |
Efgartigimod PH20 SC
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Overall Study
STARTED
|
64
|
|
Overall Study
COMPLETED
|
17
|
|
Overall Study
NOT COMPLETED
|
47
|
Reasons for withdrawal
| Measure |
Efgartigimod PH20 SC
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Overall Study
Adverse Event
|
5
|
|
Overall Study
Death
|
1
|
|
Overall Study
Lost to Follow-up
|
2
|
|
Overall Study
Participant-specified withdrawal criterion met
|
1
|
|
Overall Study
Physician Decision
|
3
|
|
Overall Study
Study terminated by sponsor
|
26
|
|
Overall Study
Withdrawal by Subject
|
7
|
|
Overall Study
Withdrawal of consent
|
2
|
Baseline Characteristics
A Phase 3 Study to Evaluate the Long-term Safety, Tolerability and Efficacy of Efgartigimod PH20 SC in Adult Participants With Bullous Pemphigoid
Baseline characteristics by cohort
| Measure |
Efgartigimod PH20 SC
n=64 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Age, Continuous
|
70.6 years
STANDARD_DEVIATION 10.17 • n=24 Participants
|
|
Sex: Female, Male
Female
|
48 Participants
n=24 Participants
|
|
Sex: Female, Male
Male
|
16 Participants
n=24 Participants
|
|
Race/Ethnicity, Customized
Asian
|
10 Participants
n=24 Participants
|
|
Race/Ethnicity, Customized
White
|
52 Participants
n=24 Participants
|
|
Race/Ethnicity, Customized
Other
|
2 Participants
n=24 Participants
|
|
Race/Ethnicity, Customized
Hispanic or Latino
|
1 Participants
n=24 Participants
|
|
Race/Ethnicity, Customized
Not Hispanic or Latino
|
63 Participants
n=24 Participants
|
PRIMARY outcome
Timeframe: Up to 56 weeksPopulation: Safety analysis set: all participants who rolled over from ARGX-113-2009, provided informed consent for ARGX-113-2010, and received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010.
Adverse events, Serious Adverse event and Adverse events of special interest. Adverse events in the 'Infections and infestations' SOC were defined as AESIs because efgartigimod causes a transient reduction in total IgG levels.
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=50 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Number of Participants With Treatment-emergent AEs, SAEs and AESIs
AE
|
40 Participants
|
|
Number of Participants With Treatment-emergent AEs, SAEs and AESIs
SAE
|
13 Participants
|
|
Number of Participants With Treatment-emergent AEs, SAEs and AESIs
AESI
|
25 Participants
|
PRIMARY outcome
Timeframe: Up to 56 weeksPopulation: Safety analysis set: all participants who rolled over from ARGX-113-2009, provided informed consent for ARGX-113-2010, and received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010.
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=50 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Number of Participants Who Discontinued Treatment Because of Safety Concerns
|
4 Participants
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Only participants evaluable for CRoff for \>=8 weeks are reported here.
CRoff = complete remission while receiving efgartigimod PH20 SC and being off oral corticosteroid therapy for at least 8 weeks. Complete remission is defined as the absence of new lesions, complete healing of existing lesions and absence of pruritus.
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=18 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Number of Participants Achieving CRoff for ≥ 8 Weeks
|
3 Participants
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Only participants evaluable for CRoff or PRoff for \>=8 weeks are reported here.
CRoff / PRoff = complete or partial remission while receiving efgartigimod PH20 SC and being off oral corticosteroid therapy for at least 8 weeks. Complete remission is defined as the absence of new lesions, complete healing of existing lesions and absence of pruritus. Partial remission is defined as the presence of only new transient lesions.
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=17 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Number of Participants Achieving CRoff or PRoff for ≥ 8 Weeks
|
3 Participants
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Only participants evaluable for CRmin for \>=8 weeks are reported here.
Minimal oCRmin = complete remission while being on minimal dose of OCS for ≥ 8 weeks. OCS = oral corticosteroid. Complete remission is defined as the absence of new lesions, complete healing of existing lesions and absence of pruritus Minimal OCS therapy is defined as ≤0.10 mg/kg/day of prednisone (or an equivalent dose of another oral corticosteroid)
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=13 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Number of Participants Achieving CRmin for ≥ 8 Weeks
|
4 Participants
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Only participants evaluable for CR while off both OCS therapy and Efgartigimod PH20 SC for \>=8 weeks are reported here.
CR = complete remission; OCS = oral corticosteroids; Complete remission is defined as the absence of new lesions, complete healing of existing lesions and absence of pruritus
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=46 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Number of Participants Achieving Complete Remission While Off Both Oral Corticosteroids and Efgartigimod PH20 SC for ≥ 8 Weeks
|
10 Participants
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Only participants evaluable for CR or PR while off both OCS therapy and Efgartigimod PH20 SC for \>=8 weeks are reported here.
CR = complete remission; PR = partial remission; OCS = oral corticosteroids Complete remission is defined as the absence of new lesions, complete healing of existing lesions and absence of pruritus. Partial remission is defined as the presence of only new transient lesions.
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=46 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Number of Participants Achieving CR or PR While Off Both OCS and Efgartigimod PH20 SC for ≥ 8 Weeks
|
10 Participants
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Only participants evaluable for duration of sustained remission are reported here.
Sustained remission is defined as healing of lesions with no nontransient lesions (ie, BPDAI activity score of 0) and absence of pruritus while the participant was off concurrent BP therapy (and, for participants enrolled prior to protocol amendment 2, efgartigimod PH20 SC) for ≥8 weeks. New lesions that heal within 1 week or pruritus lasting \<1 week and clearing without treatment were not considered to change the condition of sustained remission.
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=7 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Duration of Sustained Remission
|
NA days
Interval 54.0 to
The median survival time and upper 95% CI could not be calculated due to insufficient number of participants with events
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Rollover set: all participants who rolled over from ARGX-113-2009 and provided informed consent for ARGX-113-2010. Only participants evaluable for relapse from CDA, CR or PR onset are reported here.
Relapse is defined as the appearance of 3 or more new lesions a month or at least 1 large lesion that did not heal within 1 week, or extension of established lesions or daily pruritus in a participant who had achieved CDA (Control of disease activity): the point at which new lesions cease to form and established lesions begin to heal, and pruritic symptoms start to abate
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=63 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Number of Participants Who Relapsed
|
37 Participants
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Only participants evaluable for time to relapse from CDA, CR or PR onset are reported here.
Relapse is defined as the appearance of 3 or more new lesions a month or at least 1 large lesion that did not heal within 1 week, or extension of established lesions or daily pruritus in a participant who had achieved CDA (Control of disease activity): the point at which new lesions cease to form and established lesions begin to heal, and pruritic symptoms start to abate
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=37 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Time to Relapse
|
169.0 days
Interval 108.0 to 301.0
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Only participants with an assessment at baseline and at least one post-baseline assessment are reported here.
The Bullous Pemphigoid Disease Area Index (BPDAI) is an internationally validated tool to objectively measure disease activity. The BPDAI differentiates scores for skin (erosions/blisters and urticaria/erythema) and mucous membrane activity in several anatomical locations. BPDAI activity scores range from 0 to 360, with a higher score representing more severe disease.
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=49 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
BPDAI Activity Score, Percent Change From Baseline to Last Assessment
|
0.15 Percent change
Standard Deviation 118.361
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Only participants with an assessment at baseline and at least one post-baseline assessment are reported here.
The Investigator Global Assessment of Bullous Pemphigoid (IGA-BP) is a tool used to asses BP disease activity and severity. The IGA-BP categorizes the severity of BP on a numerical scale of 0 (clear) to 4 (severe).
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=63 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
IGA-BP Score at Last Assessment
0 - Clear
|
28 Participants
|
|
IGA-BP Score at Last Assessment
1 - Almost clear
|
8 Participants
|
|
IGA-BP Score at Last Assessment
2 - Mild
|
19 Participants
|
|
IGA-BP Score at Last Assessment
3 - Moderate
|
4 Participants
|
|
IGA-BP Score at Last Assessment
4 - Severe
|
4 Participants
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Only participants with an assessment at baseline and at least one post-baseline assessment are reported here.
The Itch Numerical Rating Scale (NRS) is used to indicate pruritic symptoms of BP. The score varies between 0 (best outcome) to 10 (worst outcome)
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=63 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Itch NRS 24-hour Average Score, Change From Baseline to Last Assessment
|
0.3 score on a scale
Standard Deviation 3.07
|
SECONDARY outcome
Timeframe: Up to 56 weeksPopulation: Only participants evaluable for treatment failure are reported here.
Treatment failure is defined as the absence of CDA despite receiving efgartigimod PH20 SC with escalated dosages of prednisone (or equivalent OCS)
Outcome measures
| Measure |
Efgartigimod PH20 SC
n=50 Participants
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Number of Participants Who Failed Treatment
|
0 Participants
|
Adverse Events
Efgartigimod PH20 SC
Serious adverse events
| Measure |
Efgartigimod PH20 SC
n=50 participants at risk
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Infections and infestations
Urinary tract infection
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Metabolism and nutrition disorders
Hyperkalaemia
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Neoplasms benign, malignant and unspecified (incl cysts and polyps)
Prostate cancer recurrent
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Neoplasms benign, malignant and unspecified (incl cysts and polyps)
Squamous cell carcinoma of skin
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Respiratory, thoracic and mediastinal disorders
Dyspnoea
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Cardiac disorders
Cardiac failure
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Gastrointestinal disorders
Abdominal distension
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
General disorders
Condition aggravated
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
General disorders
General physical health deterioration
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
General disorders
Oedema peripheral
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Infections and infestations
Appendicitis
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Infections and infestations
Gastroenteritis viral
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Infections and infestations
Herpes zoster
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Infections and infestations
Pneumonia
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Infections and infestations
Sepsis
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Infections and infestations
Septic shock
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Infections and infestations
Staphylococcal bacteraemia
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Infections and infestations
Streptococcal sepsis
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Blood and lymphatic system disorders
Anaemia
|
2.0%
1/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
Other adverse events
| Measure |
Efgartigimod PH20 SC
n=50 participants at risk
Participants rolling over from ARGX-113-2009 study, eligible to receive efgartigimod PH20 SC in this study.
|
|---|---|
|
Gastrointestinal disorders
Diarrhoea
|
6.0%
3/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Gastrointestinal disorders
Nausea
|
6.0%
3/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
General disorders
Injection site paraesthesia
|
8.0%
4/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
General disorders
Oedema peripheral
|
8.0%
4/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Infections and infestations
Nasopharyngitis
|
8.0%
4/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Infections and infestations
Urinary tract infection
|
8.0%
4/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Musculoskeletal and connective tissue disorders
Arthralgia
|
10.0%
5/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Musculoskeletal and connective tissue disorders
Back pain
|
10.0%
5/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Psychiatric disorders
Insomnia
|
6.0%
3/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
|
Skin and subcutaneous tissue disorders
Pruritus
|
6.0%
3/50 • Up to 56 weeks
Adverse events are reported for the safety analysis set which includes the 50 participants who received at least 1 dose of efgartigimod PH20 SC in ARGX-113-2010. Any clinically significant changes occurring during the study were reported as adverse events.
|
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place