Un estudio para evaluar la eficacia, seguridad y farmacocinética de la monoterapia con axatilimab en participantes japoneses con enfermedad de injerto contra huésped crónica activa recurrente o refractaria

Axatilimab at the protocol-defined dose.

IV infusion

• Axatilimab

ORR was defined as the percentage of participants with a physician-assessed complete response (CR) or a physician-assessed partial response (PR), evaluated as defined by the 2014 National Institutes of Health (NIH) Consensus Development Project on Criteria for Clinical Trials in chronic graft-versus-host disease (cGVHD). A participant was considered an objective responder if they had an overall response of CR or PR at any timepoint up to the beginning of Cycle 7. CR was defined as the resolution of all manifestations in each organ or site, and PR was defined as improvement in at least 1 organ or site without progression in any other organ or site.

The mLSS is a 28-item instrument comprising 7 subscales, designed to assess the impact of cGVHD on a participant's symptoms. Participants were asked to indicate the degree of "bother" during the past 7 days due to symptoms in 7 domains (skin, eyes and mouth, breathing, eating and digestion, muscles and joints, energy, emotional distress) potentially affected by cGVHD. A mLSS responder is defined as a participant who achieved at least a 7-point improvement from baseline in the normalized mLSS score. This score is on a 0-100 scale, calculated as the average of the subscale scores.

ORR was defined as the percentage of participants with a physician-assessed CR or a physician-assessed PR, evaluated as defined by the 2014 NIH Consensus Development Project on Criteria for Clinical Trials in cGVHD. A participant was considered an objective responder if they had an overall response of CR or PR at any post-baseline visit. CR was defined as the resolution of all manifestations in each organ or site, and PR was defined as improvement in at least 1 organ or site without progression in any other organ or site.

Duration of response was defined as the time from the first response of either CR or PR until progression of cGVHD, start of another anti-GVHD treatment, or death from any cause, whichever was earlier. CR was defined as the resolution of all manifestations in each organ or site, and PR was defined as improvement in at least 1 organ or site without progression in any other organ or site. DOR was assessed for participants whose first CR or PR occurred during the first 6 treatment cycles. A response was followed until the response ended, regardless of whether the response ended during the first 6 treatment cycles or after Cycle 6.

Organ-specific response rate was defined as the percentage of participants with a CR or PR for the 9 individual organs based on the 2014 NIH Consensus Development Project on Criteria for Clinical Trials in cGVHD (skin, eyes, mouth, esophagus, upper gastrointestinal (GI) tract, lower GI, liver, lungs, and joints and fascia) in participants with each corresponding organ involvement at baseline.

Participants may have been taking a corticosteroid upon study entry. At the discretion of the investigator, the corticosteroid dose may have been tapered after the first 4 weeks of study drug administration for participants who achieved either a PR or CR. Percent reduction was calculated as the ([difference between the baseline value and the post-baseline value]/divided by the baseline value) x 100.

Participants may have been taking a corticosteroid upon study entry. At the discretion of the investigator, the corticosteroid dose may have been tapered after the first 4 weeks of study drug administration for participants who achieved either a PR or CR.

An adverse event was defined as any untoward medical occurrence associated with the use of a drug in humans, whether or not it is considered drug related. An AE could therefore have been any unfavorable or unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of study drug. For the purposes of analysis, all AEs were considered to be TEAEs unless the AE could unequivocally be defined as not treatment emergent.

An adverse event was defined as any untoward medical occurrence associated with the use of a drug in humans, whether or not it is considered drug related. For the purposes of analysis, all AEs were considered to be TEAEs unless the AE could unequivocally be defined as not treatment emergent. The severity of AEs was assessed using Common Terminology Criteria for Adverse Events version 5.0 (CTCAE v5.0) Grades 1 through 5. Grade 1: mild; asymptomatic or mild symptoms; clinical or diagnostic observations only; treatment not indicated. Grade 2: moderate; minimal, local, or noninvasive treatment indicated; limiting age-appropriate activities of daily living. Grade 3: severe or medically significant but not immediately life-threatening; hospitalization or prolongation of hospitalization indicated; disabling; limiting self-care activities of daily living. Grade 4: life-threatening consequences; urgent treatment indicated. Grade 5: fatal.

The Karnofsky/Lansky performance status allows participants to be classified as to their functional impairment on a scale from 0 to 100. The lower the score, the worse the survival for most serious illnesses. The score can be used to compare the effectiveness of different therapies and to assess the prognosis in individual participants. The Karnofsky scale is designed for participants aged 16 years and older, and the Lansky scale is designed for participants younger than 16 years. Change from baseline was calculated as the post-baseline value minus the baseline value.

Antibodies to axatilimab were evaluated in plasma samples collected from all participants.

Plasma samples were collected for pharmacokinetic (PK) analysis.