New Analyses of Esbriet (Pirfenidone) in Idiopathic Pulmonary Fibrosis
Data presented at European respiratory congress (Sept. 3)
InterMune, Inc., based in Brisbane, Calif., announced on September 3 that new analyses of data from the RECAP extension study of Esbriet (pirfenidone) were presented at the 2012 Annual Congress of the European Respiratory Society (ERS) in Vienna, Austria.
The RECAP study is an ongoing open-label extension trial evaluating the long-term administration of Esbriet in patients who completed InterMune's phase III CAPACITY program. The CAPACITY program (studies 004 and 006) was designed to evaluate the safety and efficacy of Esbriet in patients with idiopathic pulmonary fibrosis (IPF) with mildly or moderately impaired lung function.
The new analyses evaluated forced vital capacity (FVC) and survival in 178 patients who received placebo in the CAPACITY program and who were newly treated with Esbriet in the RECAP extension study. These analyses showed that patients with mild-to-moderate IPF newly treated with Esbriet in RECAP for 60 weeks had similar FVC and survival outcomes compared with patients treated with Esbriet for the same duration in CAPACITY.
The first analysis examined the proportion of patients at week 60 with an FVC decrement of 10% or greater — an outcome that is predictive of mortality. Analysis of pooled data from CAPACITY demonstrated that treatment with Esbriet resulted in a 32% reduction in the proportion of patients who experienced an FVC decrement of at least 10% at week 60 (P = 0.011). A comparison of outcomes in patients newly treated with Esbriet in RECAP showed similar results: the proportion of patients who experienced a 10% or greater decline in FVC at week 60 was 16.3% among patients newly treated with Esbriet in RECAP compared with 16.8% in the Esbriet group in CAPACITY. The proportion of placebo-treated patients meeting this criterion in CAPACITY was 24.8%.
The second analysis was based on the mean change from baseline in the percent predicted FVC in the entire population of patients. The analysis of data at week 60 showed that the mean change in the percent predicted FVC in patients newly treated with Esbriet in RECAP was –5.8%; the mean change over the corresponding interval during CAPACITY was –7.0% in patients treated with Esbriet and –9.4% in patients treated with placebo. Analysis of data at earlier time points also showed similar results between patients newly treated with Esbriet in RECAP and those originally treated with Esbriet in CAPACITY.
The last analysis examined overall survival from baseline to week 60 in patients newly treated with Esbriet during RECAP. While neither RECAP nor CAPACITY was powered to evaluate the effect of treatment on survival, analyses showed that overall survival at 60 weeks after initiation of therapy was similar in patients newly treated with Esbriet in RECAP and CAPACITY, and greater than that of patients who were treated with placebo in CAPACITY. In addition, fewer treatment-emergent deaths (defined as deaths occurring within 28 days of the last dose of study drug) were observed among Esbriet-treated patients in both RECAP and CAPACITY compared with patients who were treated with placebo during CAPACITY. Treatment-emergent death occurred in 3.4% and 2.9% of Esbriet-treated patients in RECAP and CAPACITY, respectively, compared with 5.8% of patients treated with placebo in CAPACITY.
According to the company, these results provide further evidence to support the clinical efficacy and safety of Esbriet in patients with IPF. Esbriet is an orally active drug that inhibits the synthesis of TGF-beta, a chemical mediator that controls several cell functions, including proliferation and differentiation, and that plays a key role in fibrosis. It also inhibits the synthesis of TNF-alpha, a cytokine that is known to have an active role in inflammation.
InterMune is conducting a phase III study — ASCEND — to support the regulatory registration of Esbriet for the treatment of IPF in the U.S.
The company expects to complete patient enrollment around the end of 2012.
For more information, visit the InterMune Web site.