A Study to Evaluate of the Efficacy and Safety of Imsidolimab (ANB019) in the Treatment of Acneiform Rash

The number of facial inflammatory lesions (papules and pustules) on the face (excluding the neck and scalp area) was counted. Papule was a small, solid elevation 5 mm or less in diameter. Pastule was a small, circumscribed elevation of the skin that contains yellow-white exudate.

The acneiform rash CTCAE grading scale of severity was 6-point scale ranging from 0-5.

Scale 0=no evidence of rash. Scale 1= papules and/or pustules covering <10% body surface area (BSA), which may or may not be associated with symptoms of pruritus or tenderness.

Scale 2=papules and/or pustules covering 10-30% BSA, which may or may not be associated with symptoms of pruritus or tenderness; associated with psychosocial impact; limiting instrumental activities of daily living (ADL); papules and/or pustules covering >30% BSA with or without mild symptoms.

Scale 3=papules and/or pustules covering >30% BSA with moderate or severe symptoms; limiting self-care ADL; associated with local superinfection with oral antibiotics.

Scale 4=life-threatening consequences; papules and/or pustules covering any %BSA, which may or may not be associated with symptoms of pruritus or tenderness and are associated with extensive superinfection with intravenous (IV) antibiotics indicated.

Scale 5=death.

Time to first response of 1 grade improvement from baseline on the acneiform rash CTCAE grading scale: Date of the first response of 1 grade improvement from baseline on the acneiform rash CTCAE grading scale - Date of the first dose of study treatment (or from randomization for any participant randomized but not treated) + 1.

The MESTT grading scale of the acneiform rash severity was a 3-point scale ranging from 1 to 3:

Scale 1 = 1A: papules or pustules ≤5; OR 1 area of erythema or edema <1 centimeter (cm) in size. 1B: papules or pustules ≤5; OR 1 area of erythema or edema <1 cm in size; AND pain or pruritus.

Scale 2 = 2A: papules or pustules 6-20; OR 2-5 areas of erythema or edema <1 cm in size. 2B: Papules or pustules 6-20; OR 2-5 areas of erythema or edema <1 cm in size; AND pain, pruritus, or effect on emotions or functioning.

Scale 3 = 3A: papules or pustules > 20; OR more than 5 areas of erythema or edema <1 cm in size. 3B: papules or pustules > 20; OR more than 5 areas of erythema or edema <1 cm in size; AND pain, pruritus, or effect on emotions or functioning.

Grading was performed individually for the face, scalp, chest, and back. The sum of all body region scores yielded the total score (range: 4 to 12).

Time to first response of 1 grade improvement from baseline on the acneiform rash modified MESTT grading scale (total score): Date of onset of the first response of 1 grade improvement from baseline on the acneiform rash modified MESTT grading scale (total score) - Date of the first dose of study treatment (or from randomization for any participant randomized but not treated) + 1.

The MESTT grading scale of the acneiform rash severity was a 3-point scale ranging from 1 to 3:

Scale 1 = 1A: papules or pustules ≤5; OR 1 area of erythema or edema <1cm in size. 1B: papules or pustules ≤5; OR 1 area of erythema or edema <1 cm in size; AND pain or pruritus.

Scale 2 = 2A: papules or pustules 6-20; OR 2-5 areas of erythema or edema <1 cm in size. 2B: Papules or pustules 6-20; OR 2-5 areas of erythema or edema <1 cm in size; AND pain, pruritus, or effect on emotions or functioning.

Scale 3 = 3A: papules or pustules > 20; OR more than 5 areas of erythema or edema <1 cm in size. 3B: papules or pustules > 20; OR more than 5 areas of erythema or edema <1 cm in size; AND pain, pruritus, or effect on emotions or functioning.

Grading was performed individually for the face. The score ranged from 1 to 3.

Time to first response of 1 grade improvement from baseline on the acneiform rash modified MESTT grading scale (facial assessment): Date of onset of the first response of 1 grade improvement from baseline on the acneiform rash modified MESTT grading scale (facial assessment) - Date of the first dose of study treatment (or from randomization for any participant randomized but not treated) + 1.

The intensity of pruritus was evaluated by asking participants to assign a numerical score representing the worst intensity over the last 24 hours of their symptoms on a scale from 0 to 10, with 0 indicating no itch and 10 indicating the worst imaginable itch.

The intensity of pruritus was evaluated by asking participants to assign a numerical score representing the worst intensity over the last 24 hours of their symptoms on a scale from 0 to 10, with 0 indicating no itch and 10 indicating the worst imaginable itch.

The intensity of pain was evaluated by asking participants to assign a numerical score representing the worst intensity over the last 24 hours of their symptoms on a scale from 0 to 10, with 0 indicating no pain and 10 indicating the worst imaginable pain.

The intensity of pain was evaluated by asking participants to assign a numerical score representing the worst intensity over the last 24 hours of their symptoms on a scale from 0 to 10, with 0 indicating no pain and 10 indicating the worst imaginable pain.

The FACT-EGFRi-18 was an 18-item likert-scaled questionnaire, arranged in three dimensions: physical (seven items), social/emotional (six items), and functional well-being (five items). The response scores ranged from 0 (not at all) to 4 (very much).

The total score was obtained by multiplying the sum of the subscale by the number of items in the scale (18), and then dividing by the number of items actually answered.

The total score ranged from 0-72 with a higher score represented a high level of symptomatology (problems).

An adverse event (AE) was any untoward medical occurrence in a participant temporally associated with the use of a study treatment, whether or not considered related to study treatment. An AE could therefore be any unfavorable and unintended sign (including abnormal laboratory finding), symptom, or disease temporally associated with use of study treatment that did not necessarily have a causal relationship with this treatment. An AE was considered "serious" if there was any of the following outcomes: death, life-threatening, Inpatient hospitalization or prolongation of existing hospitalization, persistent or significant incapacity or substantial disruption of ability to conduct normal life functions, congenital anomaly/birth defect, other important medical events. An AE was considered treatment-emergent if the date of onset was during or after first dose of study treatment, or if the AE present at baseline worsened in either intensity or frequency after first dose of study treatment.