Avatrombopag for the Treatment of Thrombocytopenia in Pediatric Subjects With Immune Thrombocytopenia for ≥6 Months

Phase 3

Active, not recruiting

Brief Summary: A Phase 3b Study to Evaluate the Efficacy and Safety of Avatrombopag for the Treatment of Thrombocytopenia in Pediatric Subjects with Immune Thrombocytopenia for ≥6 Months

Detailed Description: Subjects will be randomized in to blinded therapy of avatrombopag or placebo in a 3:1 ratio for a period of 12 weeks. Subjects who complete the 12 week treatment period and are eligible may continue to the open label extension phase which will last 2 years.

Recruitment & Eligibility

Inclusion Criteria

Male or female participants ≥1 and <18 years of age at Screening and Baseline with a diagnosis of primary ITP for ≥6 months duration and has had an insufficient response to a previous treatment, in the opinion of the Investigator.
Participant has an average of 2 platelet counts <30×10^9/L with no single count >35×10^9/L in the screening period

Exclusion Criteria

Participants must not have a known history of secondary ITP, any history of arterial or venous thrombosis, including partial or complete thrombosis, known inherited thrombocytopenia, a history of myelodysplastic syndrome (MDS) or known history of congenital heart abnormalities or arrhythmias.

Arm && Interventions

Group	Intervention	Description
Experimental: Avatrombopag Double Blind	Avatrombopag	Study is 3:1 randomization ratio (avatrombopag to placebo). Investigational product administered orally once daily for 12 weeks
Placebo Comparator:Placebo Double Blind	Placebo	Study is 3:1 randomization ratio (avatrombopag to placebo). Investigational product administered orally once daily for 12 weeks
Avatrombopag Open Label Extension	Avatrombopag	Investigational product administered orally for up to 2 years.

Primary Outcome Measures

Name	Time	Method
Durable Platelet Response	Last 8 weeks of 12 week treatment regimen	The proportion of subjects achieving at least 6 out of 8 weekly platelet counts ≥50×10\^9/L during the last 8 weeks of the 12 week Treatment Period in the Core Phase, in the absence of rescue medication
Alternative Primary: Platelet Response	12 weeks of treatment	The proportion of subjects for whom at least 2 consecutive platelet assessments are ≥50×10\^9/L over the 12 weeks of treatment in the Core Phase in the absence of rescue medication.

Secondary Outcome Measures

Name	Time	Method
Percentage of Weeks Platelet Count ≥50×10^9/L	12 weeks of treatment	The percentage of weeks subjects have a platelet count ≥50×10\^9/L during 12 weeks of treatment in the Core Phase, in the absence of rescue therapy.
Platelet Response at Day 8	Day 8	The proportion of subjects with a platelet count ≥50×10\^9/L at day 8, in the absence of rescue therapy.
Percentage of Weeks Platelet Count Between ≥50×10^9/L and ≤150×10^9/L	12 weeks of treatment	The percentage of weeks subjects have a platelet count between ≥50×10\^9/L and ≤150×10\^9/L, during 12 weeks of treatment in the Core Phase, in the absence of rescue therapy.
Rescue Medications	12 weeks of treatment	The proportion of subjects who require rescue medications during 12 weeks of treatment in the Core Phase of the study.
Incidence of Any Bleeding Event (WHO Grade 1-4)	12 weeks of treatment	Overall incidence of bleeding events associated with ITP measured using the WHO Bleeding Scale (Grade 1-4).

Locations (62): Site 112
🇺🇸
Phoenix, Arizona, United States
Site 103
🇺🇸
Long Beach, California, United States
Site 119
🇺🇸
Orange, California, United States
Site 109
🇺🇸
Sacramento, California, United States
Site 101
🇺🇸
San Francisco, California, United States
Site 111
🇺🇸
Aurora, Colorado, United States
Site 120
🇺🇸
Wilmington, Delaware, United States
Site 117
🇺🇸
Gainesville, Florida, United States
Site 116
🇺🇸
Atlanta, Georgia, United States
Site 107
🇺🇸
Peoria, Illinois, United States
Scroll for more (52 remaining)
Site 112
🇺🇸Phoenix, Arizona, United States