Gilead presents new improved Letairis data for hypertension

Long-term data (mean exposure = 71 weeks; maximum exposure = 148 weeks) from an integrated analysis of 383 patients with idiopathic pulmonary arterial hypertension (IPAH) or PAH associated with connective tissue disease (PAH-CTD), HIV infection or anorexigen use who received at least one dose of Letairis (ambrisentan) (2.5, 5 or 10mg once-daily) in one of the 12-week phase III placebo-controlled studies (XYZ-1 or XYZ-2) or in the long-term extension study for XYZ-1 and XYZ-2 (XYZ-E).

Patients who received ambrisentan in Aries -1 or Aries -2 remained on their current dose in Aries-E. Patients who received placebo during previous studies were randomized to ambrisentan (Aries -1: 5 or 10mg; Aries -2: 2.5 or 5mg) in Aries -E. Efficacy and safety assessments were measured from the time of first dose of ambrisentan.

At baseline, approximately 89% of patients were classified as having WHO Class II or III symptoms. Baseline six-minute walk distance (6MWD) for patients in the 2.5, 5 and 10 mg groups were 350±87 m, 348±87 m and 342±81 m, respectively. Patients in the 2.5, 5 and 10mg groups had baseline Borg dyspnea index (BDI) scores of 4.1±2.7, 3.8±2.3 and 2.8±2.1, respectively.

Improvements in the non placebo-adjusted 6MWD observed at week 12 for the 2.5, 5 and 10mg groups (32±6.1 m, 36±5.7 m and 39±6.1 m, respectively) were maintained through week 48 of treatment (34±10.9 m, 41±7.9 m and 46±7.7 m, respectively). Improvements in WHO functional class and BDI were also maintained with long-term ambrisentan treatment.

Gilead Sciences has presented new data from the phase III Aries studies evaluating Letairis, an ETA-selective endothelin receptor antagonist in patients with pulmonary arterial hypertension.