American Journal of Cardiovascular Drugs

, Volume 19, Issue 2, pp 203–209 | Cite as

Long-Term Effects of Bosentan on Cardiovascular Events in Hispanic Patients with Intermittent Claudication: Four-Year Follow-up of the CLAU Trial

The CLAU Randomized Trial Long-Term Outcome
  • Joaquin De Haro
  • Silvia BledaEmail author
  • Carmen Gonzalez-Hidalgo
  • Ignacio Michel
  • Francisco Acin
Original Research Article



The Clinical and Endothelial Function Assessment after Endothelin Receptor Antagonist (CLAU) trial demonstrated the effect of bosentan on the endothelial function, inflammatory status and claudication distance in Hispanic patients with incipient peripheral arterial disease (PAD). Our aim was to assess the protective effect on cardiovascular events of bosentan versus conventional anti-atherosclerosis therapy.


CLAU included 56 patients with intermittent claudication, randomized 1:1 to receive bosentan for 12 weeks (n = 27) or placebo (n = 29), associating the best medical treatment. Log-rank and hazard ratio (HR) analyses were performed to estimate the relative efficacy of bosentan in preventing incidence of major adverse events (MAE) including target limb revascularization (TLR), amputation, myocardial infarction (MI), and all-cause death; major cardiovascular adverse events (MACE) including TLR, amputation, MI, stroke, and cardiovascular-cause death; and major adverse limb events (MALE), which combines TLR and amputation.


During the follow-up period (34 ± 5 months), five MAE occurred in the control group only (17.2%), including two TLR, one amputation, one stroke, and an MI. The ratio of event-free survival for MAE to 3 years follow-up was higher in the group treated with bosentan (100% vs 66%, p = 0.01, HR = 76; 95% confidence interval 0.05–104,677, p = 0.24). A similar trend was observed in incidence of MACE (100% vs 66%, p = 0.01) and MALE (100% vs 80%, p = 0.15).


Treatment with bosentan in the early low-to-mild stages of PAD may prevent cardiovascular events and the need for lower limb revascularization in the Hispanic population.

Trial Registration identifier NCT25102012.


Compliance with Ethical Standards

Conflict of interest

The authors, Joaquin De Haro, Silvia Bleda, Carmen Gonzalez Hidalgo, Ignacio Michel, and Francisco Acin, declare they have no conflicts of interest relevant to the content of this article.


This clinical trial was funded by a research Grant from the Foundation of the Spanish Society of Angiology and Vascular Surgery.


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Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  1. 1.Angiology and Vascular Surgery Department, Getafe University HospitalMadridSpain

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