Bullous Pemphigoid
Conditions
Brief summary
The purpose of this study is to evaluate the safety of efgartigimod PH20 SC over a longer period of time in adult participants with moderate-to-severe bullous pemphigoid (BP) who have completed ARGX-113-2009 study. The study will also evaluate the efficacy of efgartigimod PH20 SC. Eligible participants can roll over from the main study (ARGX-113-2009) to this open-label extension study (ARGX-113-2010). The study consists of a treatment period of up to 48 weeks in which participants could receive efgartigimod PH20 SC according to their clinical status. After the first 5 visits, the participants will visit the study centres at least once every 4 weeks. The participants who are not receiving efgartigimod PH20 SC (after the main study or currently on the study), will enter an observation period with study visits at least once every 8 weeks. If the participant relapses, they can re-enter the treatment period where they will receive efgartigimod PH20 SC. The treatment and observation period is followed by a follow-up period of 8 weeks. Oral or topical corticosteroids can be administered at the investigator's discretion.
Interventions
BIOLOGICALefgartigimod PH20 SC
Subcutaneous injection of efgartigimod coformulated with rHuPH20, a permeation enhancer
DRUGPrednisone
Oral Prednisone
Sponsors
argenx
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Has completed the week 36 visit of ARGX-113-2009 * Is capable of providing signed informed consent and complying with protocol requirements * Agrees to use contraceptive measures consistent with local regulations and the following: Women of childbearing potential must have a negative urine pregnancy test at baseline before receiving the study drug and must use one of the contraception methods described in the protocol from signing the ICF until the last dose of the study drug
Exclusion criteria
* Clinically significant disease, recent major surgery (within 3 months of baseline), or intends to have surgery during the study; or any other medical condition that, in the investigator's opinion would confound the results of the study or put the participant at undue risk * Known hypersensitivity to the study drug or 1 of its excipients * Permanently discontinued IMP in ARGX-113-2009 due to an adverse event (AE) considered related to the study drug and for whom the benefit/risk balance is not considered positive
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants With Treatment-emergent AEs, SAEs and AESIs | Up to 56 weeks | 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. |
| Number of Participants Who Discontinued Treatment Because of Safety Concerns | Up to 56 weeks | — |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants Achieving CRoff for ≥ 8 Weeks | Up to 56 weeks | 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. |
| Number of Participants Achieving CRoff or PRoff for ≥ 8 Weeks | Up to 56 weeks | 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. |
| Number of Participants Achieving CRmin for ≥ 8 Weeks | Up to 56 weeks | 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) |
| Number of Participants Achieving Complete Remission While Off Both Oral Corticosteroids and Efgartigimod PH20 SC for ≥ 8 Weeks | Up to 56 weeks | 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 |
| Number of Participants Achieving CR or PR While Off Both OCS and Efgartigimod PH20 SC for ≥ 8 Weeks | Up to 56 weeks | 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. |
| Duration of Sustained Remission | Up to 56 weeks | 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. |
| Number of Participants Who Relapsed | Up to 56 weeks | 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 |
| Time to Relapse | Up to 56 weeks | 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 |
| BPDAI Activity Score, Percent Change From Baseline to Last Assessment | Up to 56 weeks | 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. |
| IGA-BP Score at Last Assessment | Up to 56 weeks | 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). |
| Itch NRS 24-hour Average Score, Change From Baseline to Last Assessment | Up to 56 weeks | 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) |
| Number of Participants Who Failed Treatment | Up to 56 weeks | Treatment failure is defined as the absence of CDA despite receiving efgartigimod PH20 SC with escalated dosages of prednisone (or equivalent OCS) |
Countries
Australia, Bulgaria, China, Croatia, Czechia, Germany, Greece, Hungary, Israel, Italy, Japan, Netherlands, Serbia, Slovakia, Spain, United Kingdom, United States
Participant flow
Recruitment details
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).
Pre-assignment details
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.
Baseline characteristics
| Characteristic | — |
|---|---|
| Age, Continuous | 70.6 years STANDARD_DEVIATION 10.17 |
| Race/Ethnicity, Customized Asian | 10 Participants |
| Race/Ethnicity, Customized Hispanic or Latino | 1 Participants |
| Race/Ethnicity, Customized Not Hispanic or Latino | 63 Participants |
| Race/Ethnicity, Customized Other | 2 Participants |
| Race/Ethnicity, Customized White | 52 Participants |
| Sex: Female, Male Female | 48 Participants |
| Sex: Female, Male Male | 16 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 1 / 50 |
| other Total, other adverse events | 38 / 50 |
| serious Total, serious adverse events | 13 / 50 |
Outcome results
None listed