Phase I Safety and Tolerability Study of Staphylococcal Protein A in Adult Patients With Chronic ITP

Protalex

Status and phase: Terminated; Phase 1

Conditions: Idiopathic Thrombocytopenic Purpura (ITP)

Treatments: Drug: PRTX-100 (Staphylococcal protein A)

Study type: Interventional

Funder types: Industry

Identifiers

NCT00571467

PRTX-100A-201

Details and patient eligibility

About

The primary purpose of this study is to evaluate the safety of multiple doses of Staphylococcal protein A (PRTX-100) in adult patients with Idiopathic Thrombocytopenia Purpura (ITP). The pharmacokinetics, immunogenicity and pharmacodynamics will also be studied.

Patients will be enrolled into 1 of 3 dose groups and receive 4 weekly IV doses of PRTX-100. A Safety Monitoring Committee will review safety data through Day 28 for the first 5 patients in a dose group before escalation to the next higher dose level. Patients will be followed for 8 weeks after dosing for safety, PK, immunogenicity and effect on platelet count(pharmacodynamics).

Enrollment: 9 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Diagnosis of chronic ITP > 4 months
• Mean platelet count <50 x 10^9/L for patients not receiving corticosteroids; or mean platelet count >=50 x 10^9/L for patients receiving stable dose of corticosteroids

Exclusion criteria

• Splenectomy within 45 days of screening
• Rituximab within 6 months prior to screening
• Cyclophosphamide, vincristine, or any other non-monoclonal antibody treatment for ITP within 3 months prior to screening
• IVIG, WinRho or other anti-RhD within 30 days prior to screening

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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9 participants in 1 patient group

PRTX-100 (Staphylococcal protein A)

Experimental group

Description:

Cohort 1: 0.075 mcg/kg Cohort 2: 0.15 mcg/kg Cohort 3: 0.30 mcg/kg

Treatment:

Drug: PRTX-100 (Staphylococcal protein A)