A Real World Study of Treatment Patterns and Effectiveness of Standard of Care in Primary Immune Thrombocytopenia Patients

Second-line treatments of interest, either as monotherapy or in a combination therapy, included:

• Thrombopoietin Receptor Agonists (TPO-RAs): romiplostim, eltrombopag, avatrombopag.
• Clusters of differentiation 20 (CD20) inhibitors: rituximab
• Other therapies: fostamatinib
• Immunosuppressants: azathioprine, mycophenolate mofetil
• Splenectomy

Activities included:

• Switch to new treatment
• Restart the same second-line treatment
• Have rescue treatment without second-line treatment
• First-line treatment without second-line treatment
• Enter a treatment-free interval
• End of EHR/claims disenrollment
• Death

Treatment free interval was defined as at least 6 months with no second-line treatment or rescue treatment.

Treatment free interval was defined as at least 6 months with no second-line treatment or rescue treatment.

Reduction was defined as a discontinuation of at least one therapeutic agent with maintenance of at least one therapeutic agent.

An add-on was the inclusion of a new, additional second-line treatment ≥28 days after initiation of the initial second-line treatment.

Measured among patients with at least one platelet count within 3 months of treatment initiation.

Pre-defined platelet counts were categorized as follows:

• ≥30 × 10^9/L,
• ≥ 50 × 10^9/L, and
• ≥100 × 10^9/L

Measured among patients with at least one platelet count within 3 months of treatment initiation. No initial response was defined as platelet counts <30 × 10^9/L within 3 months of treatment initiation.

Measured among patients with at least one platelet count within 6 months of treatment initiation. Response levels were categorized as follows:

• response (≥ 50 × 10^9/L), and
• complete response (≥100 × 10^9/L)

Real-world durable response was defined as ≥75% of platelet counts ≥50 × 10^9/L with a minimum of 2 platelet measurements and without other therapies.

Real-world durable response was defined as ≥75% of platelet counts ≥50 × 10^9/L with a minimum of 2 platelet measurements and without other therapies.

Thrombotic events may have included pulmonary embolism, deep vein thrombosis, cerebral venous thrombosis, transient ischemic attack.

Healthcare visits included outpatient visits, IP admissions, intensive care unit (ICU) admissions, and ED visits.

Healthcare visits included outpatient visits, IP admissions, ICU admissions, and ED visits.

Patient responders were defined as patients who reach a response level of ≥ 50 × 10^9/L within 6 months. Treatment failure was defined as platelet count <30 × 10^9/L.

Patient responders were defined as patients who reach a response level of ≥ 50 × 10^9/L within 6 months.

Patient responders were defined as patients who reach a response level of ≥ 50 × 10^9/L within 6 months.

Patient responders were defined as patients who reach a response level of ≥ 50 × 10^9/L within 6 months.

Patient responders were defined as patients who reach a response level of ≥ 50 × 10^9/L within 6 months.

Patient responders were defined as patients who reach a response level of ≥ 50 × 10^9/L within 6 months.

Patient responders were defined as patients who reach a response level of ≥ 50 × 10^9/L within 6 months.

Patient responders were defined as patients who reach a response level of ≥ 50 × 10^9/L within 6 months. Treatment-free response was defined as platelet count ≥30 × 10^9/L at 3 months after discontinuing second-line treatment.