A Study of Aspirin and Clopidogrel in Patients With Idiopathic Pulmonary Arterial Hypertension

Kawut, Steven, MD

Status and phase

Completed

Phase 2

Conditions

Hypertension, Pulmonary

Treatments

Drug: Aspirin

Drug: clopidogrel

Study type

Interventional

Funder types

Other

NIH

Identifiers

NCT00105209

RR00645

RR00095

HL67771-01

RR15534

Details and patient eligibility

About

Rationale: Idiopathic pulmonary arterial hypertension (IPAH) is characterized by in situ thrombosis and increased thromboxane A2 (Tx-M) synthesis. While both may be attributable to abnormal platelet function, there are no studies of anti-platelet therapy in IPAH.

Objectives: The purpose of this study is to assess the effects of aspirin (ASA) and clopidogrel on platelet function and eicosanoid metabolism in patients with IPAH.

Full description

This is a randomized, double-blind, placebo-controlled crossover study of aspirin 81 mg once daily and clopidogrel 75 mg once daily. Platelet function is assessed with plasma P-selectin levels and aggregometry after exposure to adenosine diphosphate, arachidonic acid, and collagen. We will assess serum levels of thromboxane B2 and urinary metabolites of thromboxane A2 and prostaglandin I2 (Tx-M and PGI-M, respectively).

Sex

All

Ages

18+ years old

Volunteers

No Healthy Volunteers

Inclusion criteria

Diagnosis of IPAH
≥ 18 years of age
NYHA functional class I, II, or III
Clinical stability (i.e., without change in pulmonary arterial hypertension medical regimen within one month prior to enrollment).

Exclusion criteria

Other forms of PAH
A contraindication to ASA or clopidogrel
Thrombocytopenia (defined as platelet count ≤ 75,000)
History of intracranial hemorrhage or chronic thromboembolic disease
Renal failure
Inability or unwillingness to avoid non-steroidal anti-inflammatory agents, ASA, or warfarin use for the duration of the trial