By Bruno Castro, PhD
In a recent study entitled, “Initial Use of Ambrisentan plus Tadalafil in Pulmonary Arterial Hypertension” published in the prestigious New England Journal of Medicine, a worldwide team of researchers demonstrated that treatment combining ambrisentan and tadalafilsignificantly improves the clinical condition of Pulmonary Arterial Hypertension patients.
Pulmonary arterial hypertension is a common consequence of various chronic obstructive pulmonary diseases, characterized by an increase in blood pressure in pulmonary arteries due capillary obstruction, narrowing and degradation. If not treated, the disease can lead to death due to cardiorespiratory disorders and heart failure in a relatively short time frame.
Common pulmonary arterial hypertension therapeutic approaches target key cellular mechanisms that regulate pulmonary arteries’ contractility and cell proliferation. Generally, pulmonary arterial hypertension treatments act on a specific cellular event, with limited efficacy in controlling the disease. Researchers believe that disease onset results from abnormalities in different regulatory processes and not a single cellular pathway.
In this study, researchers investigated the long-term effects of a combined ambrisentan (Letairis, marketed by Gilead) andtadalafil (Cialis, marketed by Eli Lilly) therapy on clinical indicatives of disease progression (hospitalization, transplant requirement, poor treatment response, and death) in pulmonary hypertension patients that had not been previously treated for their condition. Study author Dr. Joan Albert Barberà from the August Pi Sunyer Biomedical Research Institute (IDIBAPS) and the Hospital Clinic in Barcelona, Spain stated in a press release “So far previous studies have evaluated combinations of drugs administered sequentially. This is the first work proposing the use of a combination of drugs given to patients simultaneously and since the beginning.”
The study included 500 pulmonary hypertension patients from different countries, divided into three groups: i) the combined drug group, which included 250 patients; ii) the ambrisentan alone group, including 126 patients; and iii) the tadalafil alone group, including 124 patients. The percentage of clinical failure events registered in the single drug groups reached 31%, whereas this value almost halved in the combined drug group to 18%.
These results clearly show the benefits of the combined use of ambrisentan and tadalafil over single drug approaches to treat pulmonary hypertension patients. These findings could potentially change the way pulmonary hypertension treatments are designed and administrated, as explained by Dr. Barberà: “These results will have a major impact on the treatment of patients with pulmonary hypertension. In fact, the therapeutic strategy using an initial combined treatment has been incorporated into the new European Clinical Guidelines for pulmonary hypertension, presented last week in London.”
Bruno has a PhD in Chemistry from Instituto Superior Técnico, Technical University of Lisbon, Portugal. He did his undergraduate studies in Biochemistry at the Faculty of Sciences of Lisbon University, Portugal. For the past years he was as a Postdoctoral Researcher at ICFO – The Institute of Photonic Sciences, Barcelona, Spain, working in the intersection between biophysical-chemistry, cell biology and immunology.