Clinical trial NCT06435845: Phase 2 Study on the Pharmacokinetics and Safety of RLYB212 in Pregnant Women at Higher Risk for HPA-1a Alloimmunization
Official title: A Phase 2, Multicenter, Open-label Study to Evaluate the Pharmacokinetics and Safety of RLYB212 in Pregnant Women at Higher Risk for HPA-1a Alloimmunization
Study type: INTERVENTIONAL
Overall status: ACTIVE_NOT_RECRUITING
Phase: PHASE2
Conditions: Fetal and Neonatal Alloimmune Thrombocytopenia
Lead sponsor: Rallybio
Sponsor class: INDUSTRY
First posted: 2024-05-30
Enrollment: 8
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: PREVENTION

Brief summary: The purpose of this Phase 2 study is to assess the pharmacokinetics (PK) and safety of RLYB212 in HPA-1b/b pregnant women at higher risk for HPA-1a alloimmunization and FNAIT.

Detailed description: This study is a single-arm, open-label, multicenter study of RLYB212 in HPA-1b/b pregnant participants at higher risk for the occurrence of HPA-1a alloimmunization and FNAIT. A laboratory testing paradigm will be applied at screening to identify women at higher risk for HPA-1a alloimmunization. Study IPA2202 is comprised of three phases: a two-part screening phase, an antenatal treatment phase, and a postpartum follow-up phase. Study duration for each participant is anticipated to be \~44 weeks, inclusive of the screening visits through the Week 10 postpartum visit.

Eligibility criteria: Inclusion Criteria:

Pregnant women who present at Gestational Week 6 or after and confirmed to be: HPA-1b/b (HPA-1a negative), HLA-DRB3\*01:01 positive, Anti-HPA-1a alloantibody negative, Carrying an HPA-1a/b (HPA-1a positive) fetus

Exclusion Criteria:

* Prior history of HPA-1a related fetal and neonatal alloimmune thrombocytopenia
* Multiple pregnancy (more than 1 fetus)
* Prior history of platelet transfusion or other blood transfusions
* Known sensitivity and/or immediate hypersensitivity to any components of RLYB212 or its formulation
* Any co-morbid medical or obstetric condition(s), laboratory abnormality, concomitant treatment, or other reason that, in the investigator's opinion, could adversely affect the safety of the participant and/or fetus, impair the assessment of study results, or preclude compliance with the study

Primary outcomes:
measure: Number of Participants with treatment related adverse events as defined by CTCAE 5.0
timeFrame: Approx. Gestational Week (GW) <16, 16, 18, 20, 24, 26, 28, 30, 32, 34, 36, 38; at birth (~40), Post Partum (PP) Week 4, 10 week
measure: Maternal exposure to RLYB212 as measured in serum
timeFrame: Approx. GW 16, 18, 20, 24, 26, 28, 30, 32, 34, 36, 38, at birth (~40), PP Week 4
Secondary outcomes:
measure: Neonatal exposure to RLYB212 as measured in cord blood
timeFrame: At birth (~GW 40)
measure: Number of HPA-1a positive neonates with treatment related adverse events as defined by CTCAE v5.0
timeFrame: At birth (~GW 40), Approx. PP Week 4
measure: Anti-RLYB212 antibodies as measured in serum
timeFrame: Approx. GW 16, 20, 24, 28, 32, 36, at birth (~40), PP Week 4
measure: Pregnancy Outcomes: incidence of live births, spontaneous abortions, elective abortions, still births or premature births
timeFrame: At birth (~GW 40)
measure: Frequency of Neonatal Thrombocytopenia as measured by platelet count within 72 hours of delivery
timeFrame: At birth (~GW 40)
measure: Frequency of HPA-1a Alloimmunization as measured by anti-HPA-1a alloantibodies
timeFrame: Approx. PP Week 10
measure: Neonatal Outcomes: general health and overall status as defined by absolute values and percentiles
timeFrame: 4-6 weeks following delivery
Other outcomes:
Locations:
city: Leiden
country: Netherlands
facility: Leids Universitair Medisch Centrum
state: Zuid-Holland
city: Oslo
country: Norway
facility: Oslo University Hospital- Ullevål
city: Stockholm
country: Sweden
facility: Södersjukhuset
Study officials:
References: