Safety and Treatment Satisfaction in Adults With Chronic ITP After Switching to Avatrombopag From Eltrombopag or Romiplostim

Prospective, Multi-center, Open-label Study Measuring Safety and Treatment Satisfaction in Adult Subjects With Chronic Immune Thrombocytopenia (ITP) After Switching to Avatrombopag From Eltrombopag or Romiplostim

Evaluate the safety and tolerability of avatrombopag given for 90 days after stopping treatment with eltrombopag or romiplostim.

Study Overview

• Status: Completed
• Conditions: Immune Thrombocytopenia
• Intervention / Treatment: Drug: Avatrombopag Oral Tablet

Detailed Description

This Phase 4, prospective, multi-center, open-label study will evaluate safety, platelet count, and subject reported medication satisfaction in adult subjects with chronic ITP after switching to avatrombopag from eltrombopag or romiplostim. At least 100 subjects will be enrolled, 50 (±10) who have received eltrombopag and 50 (±10) who have received romiplostim for at least 90 days prior to study entry.

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • Arizona
    • Tucson, Arizona, United States, 85745
      • Sobi Site 110
  • California
    • Whittier, California, United States, 90603
      • Sobi Site 119
  • District of Columbia
    • Washington, District of Columbia, United States, 20010
      • Sobi Site 123
  • Florida
    • Miami, Florida, United States, 33143
      • Sobi Site 129
    • Ocala, Florida, United States, 34474
      • Sobi Site 120
    • Saint Petersburg, Florida, United States, 33709
      • Sobi Site 125
    • Tampa, Florida, United States, 33606
      • Sobi Site 118
  • Illinois
    • Chicago, Illinois, United States, 60612
      • Sobi Site 126
    • Peoria, Illinois, United States, 61614
      • Sobi Site 109
  • Louisiana
    • New Orleans, Louisiana, United States, 70112
      • Sobi Site 124
  • Maryland
    • Bethesda, Maryland, United States, 20817
      • Sobi Site 101
  • Nebraska
    • Lincoln, Nebraska, United States, 68506
      • Sobi Site 103
  • North Carolina
    • Chapel Hill, North Carolina, United States, 27514
      • Sobi Site 121
    • Greenville, North Carolina, United States, 27834
      • Sobi Site 116
  • Ohio
    • Cleveland, Ohio, United States, 44106
      • Sobi Site 128
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19104
      • Sobi Site 127
    • York, Pennsylvania, United States, 17403
      • Sobi Site 102
  • South Carolina
    • Rock Hill, South Carolina, United States, 29732
      • Sobi Site 104
  • Texas
    • Dallas, Texas, United States, 75246
      • Sobi Site 113
  • Utah
    • Salt Lake City, Utah, United States, 84132
      • Sobi Site 108

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Subject has been undergoing treatment for primary ITP with eltrombopag or romiplostim for at least 90 days prior to the Screening Visit/Visit 1.
• Subject has had a previous response (at any time) to either eltrombopag or romiplostim, defined as at least 2 platelet counts ≥50×10⁹/L. Subject is willing and able to comply with all aspects of the protocol, including completing the self-administered Treatment Satisfaction Medication Questionnaire (TSQM).

Exclusion Criteria:

• Subject is currently receiving chemotherapy or radiation for any form of cancer.
• Subject with conditions that are likely to prevent them from accurately and reliably completing study assessments, including evidence of moderate to severe dementia, and/or severe and progressive medical illness, as determined by the Investigator.
• Any previous avatrombopag use.
• Previous participation in this study; a subject may not re-enroll after prior discontinuation or completion.
• Enrollment in another clinical study with any investigational drug or device within 30 days of Baseline (or 5 half-lives, whichever is longer); however, participation in observational studies within the previous 30 days is permitted.

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
Other: Avatrombopag; Avatrombopag 20 mg oral tablet formulation for 90 days	Drug: Avatrombopag Oral Tablet; Avatrombopag 20 mg given daily for 90 days. Initial dose and dose adjustments will be determined by the physician along with the Doptelet prescribing information; Other Names: Doptelet

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety and Tolerability (Adverse Events)	Safety and Tolerability of Avatrombopag given for 90 days after stopping eltrombopag or romiplostim The incidence and severity of adverse events (AEs), serious adverse events (SAE) and adverse events of special interest (AESIs) will be summarized for all enrolled subjects using counts and percentages. Treatment-emergent AEs and SAEs will be summarized overall, by system organ class, and by preferred term. AESIs will be summarized by event type (thromboembolic events and bleeding events). In addition, treatment-emergent AEs will be summarized by severity and by relationship to study drug. Bleeding events reported during the study will be summarized by WHO grade.	Screening through Day 90 or End of Study

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change From Baseline TSQM Convenience Domain Score	Evaluate the change in subject reported outcomes (TSQM - Treatment Satisfaction Questionnaire for Medication) from Baseline. Convenience domain score ranges from 0 to 100, and a higher score indicates a better outcome. Mean Difference was computed as Day 90 minus Baseline and, therefore, a positive mean difference indicates an increase in the score from Baseline to Day 90.	Day 90
Change From Baseline TSQM Side Effects Domain Score	Evaluate the change in subject reported outcomes (TSQM - Treatment Satisfaction Questionnaire for Medication) from Baseline. Side Effects domain score ranges from 0 to 100, and a higher score indicates a better outcome. Mean Difference was computed as Day 90 minus Baseline and, therefore, a positive mean difference indicates an increase in the score from Baseline to Day 90.	Day 90
Change From Baseline TSQM Effectiveness Domain Score	Evaluate the change in subject reported outcomes (TSQM - Treatment Satisfaction Questionnaire for Medication) from Baseline. Effectiveness domain score ranges from 0 to 100, and a higher score indicates a better outcome. Mean Difference was computed as Day 90 minus Baseline and, therefore, a positive mean difference indicates an increase in the score from Baseline to Day 90.	Day 90
Change From Baseline TSQM Global Satisfaction Domain Score	Evaluate the change in subject reported outcomes (TSQM - Treatment Satisfaction Questionnaire for Medication) from Baseline. Global Satisfaction domain score ranges from 0 to 100, and a higher score indicates a better outcome. Mean Difference was computed as Day 90 minus Baseline and, therefore, a positive mean difference indicates an increase in the score from Baseline to Day 90.	Day 90
Proportion of Subjects Who Have a Platelet Count Between ≥50×10^9/L to ≤200×10^9/L		Day 15
Proportion of Subjects Who Have a Platelet Count Between ≥50×10^9/L to ≤200×10^9/L		Day 30
Proportion of Subjects Who Have a Platelet Count Between ≥50×10^9/L to ≤200×10^9/L		Day 60
Proportion of Subjects Who Have a Platelet Count Between ≥50×10^9/L to ≤200×10^9/L		Day 90

Collaborators and Investigators

• Sponsor: Sobi, Inc.

Study record dates

Study Major Dates

• Study Start (Actual): March 15, 2021
• Primary Completion (Actual): January 3, 2024
• Study Completion (Actual): January 3, 2024

Study Registration Dates

• First Submitted: November 11, 2020
• First Submitted That Met QC Criteria: November 19, 2020
• First Posted (Actual): November 20, 2020

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: December 20, 2024
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Keywords: ITP
• Additional Relevant MeSH Terms: Cytopenia; Pathologic Processes; Autoimmune Diseases; Immune System Diseases; Hemorrhage; Skin Manifestations; Hematologic Diseases; Blood Coagulation Disorders; Hemorrhagic Disorders; Blood Platelet Disorders; Thrombotic Microangiopathies; Purpura, Thrombocytopenic; Purpura; Thrombocytopenia; Purpura, Thrombocytopenic, Idiopathic
• Other Study ID Numbers: AVA-ITP-401

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No