Combined Letairis/Cialis Treatment Found to Improve Pulmonary Arterial Hypertension Outcomes

In a recent study titled, “Initial Use of Ambrisentan plus Tadalafil in Pulmonary Arterial Hypertension,” published in the New England Journal of Medicine, a global team of researchers demonstrated that treatment combining ambrisentan and tadalafil significantly 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 to 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 effects on 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) and tadalafil (Cialis, marketed by Eli Lilly) therapy on clinical indicators 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: the combined drug group, which included 250 patients; the ambrisentan alone group with 126 patients; and the tadalafil alone group with124 patients. The percentage of clinical failure events registered in the single drug groups reached 31%, while the value almost halved in the combined drug group to 18%.

The results show the benefits of the combined use of ambrisentan and tadalafil over single drug approaches to treat pulmonary hypertension patients. The findings could potentially change the way pulmonary hypertension treatments are designed and administrated.

“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,” Barberà said.