A Study to Assess the Concentration of Rozanolixizumab in the Breast Milk of Healthy Lactating Women

An Open-Label, Single-Dose Study to Assess the Concentration of Rozanolixizumab in the Breast Milk of Healthy Lactating Women

The purpose of the study is to assess the concentration of rozanolixizumab in mature breast milk of healthy study participants following administration of a single dose of rozanolixizumab

Study Overview

• Status: Completed
• Conditions: Healthy Participants
• Intervention / Treatment: Drug: Rozanolixizumab

• Study Type: Interventional
• Enrollment (Actual): 15
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Texas
    • San Antonio, Texas, United States, 78209
      • UP0141 2
  • Utah
    • Salt Lake City, Utah, United States, 84124
      • UP0141 1

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion criteria

• Study participant must be minimum 18 years at the time of signing the informed consent form (ICF)
• Study participant is lactating and will be at least 6 weeks postpartum on Day 1 of the study
• Study participant has voluntarily decided, prior to having knowledge of this study, to cease breast milk feeding (by any means) in relation to her current period of lactation. Study participant agrees to cease or suspend breast milk feeding by Day 1 of the study and to not resume breast milk feeding (by any means) or donate expressed breast milk for 8 weeks following administration of rozanolixizumab. Participants may decide to resume breast milk feeding 8 weeks after administration of rozanolixizumab, with the agreement that any breast milk collected (to maintain milk supply) during that 8-week period will be discarded
• Study participant is female

A female participant is eligible to participate if she is not pregnant and at least 1 of the following conditions applies:

• A woman of childbearing potential (WOCBP) who agrees to follow the contraceptive guidance during the Sampling Period and for at least 1 week after the last dose of study treatment OR
• Not a WOCBP (ie, premenopausal female with documented hysterectomy, documented bilateral salpingectomy, or documented bilateral oophorectomy)

Exclusion criteria

• Study participant has history of breast implants, breast augmentation, or breast reduction surgery
• Study participant has received live vaccine(s) within 4 weeks prior to Screening or plans to receive such vaccines during the study
• Study participant has received treatment with biologic agents (such as monoclonal antibodies including marketed drugs) within 3 months or 5 half-lives (whichever is longer) prior to dosing
• Study participant has had exposure to more than 3 new chemical entities within 12 months prior to dosing
• Study participant has had an active clinically significant infection within the last 6 weeks

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Rozanolixizumab arm; Study participants enrolled in this arm will receive a single dose of subcutaneous rozanolixizumab	Drug: Rozanolixizumab; Dose formulation: Solution for injection Route of administration: Subcutaneous infusion; Other Names: UCB7665

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Concentration of Rozanolixizumab in Breast Milk Over a 7-day Sampling Period	The concentration of Rozanolixizumab in breast milk was calculated over the 7-day sampling period. Here, '<=' denotes 'less than or equal to'; '>' denotes 'greater than'; 'min' indicates minutes; and 'hrs' indicates hours.	Predose (within 30 min) on Day 1 and at 0 to <=3, >3 to <=6, >6 to <=9, >9 to <=12, >12 to <=24, >24 to <=36, >36 to <=48, >48 to <=60, >60 to <=72, >72 to <=84, >84 to <=96, >96 to <=108, >108 to <=120, >120 to<=132, and >132 to<=144 hrs (Day 7) postdose

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Estimated Daily Infant Dosage	The estimated daily infant dosage of Rozanolixizumab from breast milk was calculated based on the concentration of Rozanolixizumab in mature human breast milk. Estimated daily infant dosage (milligram per kilogram per day [mg/kg/day]) was equal to the milk-to-plasma ratio (M/P ratio) multiplied by the average maternal plasma concentration (Cav, plasma), and the standardized mean breastmilk intake by infant, which is 150 milliliters of breast milk per kilogram of infant body weight per day (150 mL/kg/day).	Predose (within 30 min) on Day 1 and at 0 to <=3, >3 to <=6, >6 to <=9, >9 to <=12, >12 to <=24, >24 to <=36, >36 to <=48, >48 to <=60, >60 to <=72, >72 to <=84, >84 to <=96, >96 to <=108, >108 to <=120, >120 to<=132, and >132 to<=144 hrs (Day 7) postdose
Relative Infant Dose of Rozanolixizumab From Breast Milk	The relative infant dose of Rozanolixizumab from breast milk was calculated by dividing the estimated daily infant dosage (mg/kg/day) by maternal dosage (mg/kg/day) and then multiplying the result by 100.	Predose (within 30 min) on Day 1 and at 0 to <=3, >3 to <=6, >6 to <=9, >9 to <=12, >12 to <=24, >24 to <=36, >36 to <=48, >48 to <=60, >60 to <=72, >72 to <=84, >84 to <=96, >96 to <=108, >108 to <=120, >120 to<=132, and >132 to<=144 hrs (Day 7) postdose
Percentage of Participants With Treatment-emergent Adverse Events (TEAEs)	An Adverse Event (AE) was any untoward medical occurrence in a participant or clinical study participant, temporally associated with the use of study medication, whether or not considered related to the study medication. A Treatment-emergent adverse events (TEAEs) were defined as any adverse events with a start date/time on or after dosing of the study medication and up to 8 weeks inclusive after dosing of the study medication. The participant data was rounded to one decimal place.	From Day 1 Visit up to the Safety Follow-Up Visit (Day 57)

Collaborators and Investigators

• Sponsor: UCB Biopharma SRL
• Investigators: Study Director: UCB Cares, 001 844 599 2273

Study record dates

Study Major Dates

• Study Start (Actual): December 3, 2024
• Primary Completion (Actual): May 12, 2025
• Study Completion (Actual): May 12, 2025

Study Registration Dates

• First Submitted: December 2, 2024
• First Submitted That Met QC Criteria: December 2, 2024
• First Posted (Actual): December 6, 2024

Study Record Updates

• Last Update Posted (Actual): June 4, 2026
• Last Update Submitted That Met QC Criteria: May 8, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Phase 1; rozanolixizumab; UCB7665; Healthy lactating women
• Additional Relevant MeSH Terms: Immunosuppressive Agents; Immunologic Factors; Physiological Effects of Drugs; rozanolixizumab
• Other Study ID Numbers: UP0141

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Due to the small sample size in this trial, individual participant-level data cannot be adequately anonymized as there is a reasonable likelihood that individual participants could be re-identified. For this reason, data from this trial cannot be shared.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No