InterMune Reports Results from
Triple Combination Study of ITMN-191

Brisbane, Calif. -- January 12, 2008 -- InterMune, Inc. today reported top-line results from all six completed dosage cohorts of its Phase 1b clinical trial of ITMN-191 (R7227) in combination with standard-of-care Pegasys (peginterferon alfa-2a) and Copegus (ribavirin) for 14 days of treatment in hepatitis C virus (HCV) treatment-naive patients infected with HCV genotype 1. ITMN-191 is being developed in collaboration with Roche. Viral kinetic performance and safety results were reported for three cohorts each of ITMN-191 given every 12 hours (q12h) and every eight hours (q8h).

Viral Kinetic Performance

After 14 days of triple combination therapy, the median change in HCV RNA from baseline exceeded 5 logs in five of the six cohorts and was -5.4 log and -5.7 log in the best performing q12h and q8h cohorts, respectively. Considering all cohorts, HCV RNA was below the limit of quantification in nearly three-quarters (71%, or 32 of 45) of patients who received treatment with ITMN-191 after only 14 days of treatment. In all q12h and q8h cohorts, reductions in HCV RNA occurred rapidly and there was no evidence of viral rebound during ITMN-191 treatment.

Safety and Tolerability Profile

ITMN-191was generally safe and well tolerated. There were no serious adverse events (SAEs) or Grade 4 adverse events (AEs) during treatment with ITMN-191. AEs reported during study treatment (ITMN-191 or placebo) were predominantly mild to moderate in severity, typically consistent with the well-described AE profile of standard of care (SOC) and none led to treatment discontinuation.

Only four Grade 3 AEs were reported during study treatment, two of which (sciatica and back pain) were deemed by the investigator to be unrelated to ITMN-191. The other two were neutropenia and indirect bilirubin elevation. Neutropenia occurred with a similar pattern, frequency, and severity in the placebo and ITMN-191 groups. Minor and transient elevations in indirect bilirubin levels were observed in a small number of placebo and ITMN-191 patients and were deemed not clinically significant by the investigator. There were no other laboratory or ECG findings during study treatment that were attributable to ITMN-191.

A chart of the median log10 HCV RNA changes from baseline to Day 14 for each dose cohort is available on the investor relations page of InterMune's corporate website.

Dr. Stefan Zeuzem, Professor of Medicine, Chief of the Department of Medicine at the J.W. Goethe University Hospital in Frankfurt, Germany and protocol chair of this study said, "Based on the totality of the viral kinetic data, in particular BLQ [Below Limit of Quantification], a robust predictor of virologic outcome, the q12h and q8h regimens delivered very convincing viral kinetic results and appeared to perform very comparably in this 14-day study. The safety and tolerability profile of ITMN-191 in both the earlier monotherapy study and in the present triple combination study was also encouraging, as no issues of concern were observed. We look forward to the completion of the planned Phase 2b study to determine if the very promising profile of ITMN-191 observed will be confirmed."

Dan Welch, Chairman, Chief Executive Officer and President of InterMune said, "We are very pleased to report that in this 14-day study, both the q12h and q8h regimens of ITMN-191 delivered viral kinetic performance that we believe is very competitive with that reported to date for other protease inhibitors in similar experiments. In addition, the strong safety and tolerability profile of ITMN-191 observed in prior Phase 1 experiments was reinforced in this study, even in the presence of standard-of-care therapy and at doses significantly higher than those used in monotherapy."

Mr. Welch continued, "We believe that the viral kinetic and safety results reported today provide evidence that ITMN-191 has the potential to deliver superior sustained virologic response (SVR) rates on an intent-to-treat basis. In pursuit of this goal, our Phase 2b study, anticipated to begin in the second quarter of 2009, will study both q12h and q8h regimens and both 12 and 24-week treatment durations."

Phase 1b Triple Combination Trial Design

The Phase 1b randomized, double-blind, placebo-controlled, 14-day triple combination study in treatment-naive patients chronically infected with HCV genotype 1 was designed to inform the dose selection and study design of the ITMN-191 Phase 2 program. The study objectives were to assess the safety, pharmacokinetic and viral kinetic effects of various doses and regimens of ITMN-191 for 14 days in combination with Pegasys and Copegus compared to treatment with Pegasys and Copegus alone. Patient follow-up continues for 30 days following the completion of study treatment.

INFORM-1 Progress (All-oral STAT-C study)

In November 2008, Roche, InterMune and Pharmasset initiated the first all-oral combination study of direct anti-virals in the absence of interferon or ribavirin, known as the INFORM-1 study. That study has completed the first dose cohort. Results of INFORM-1 are expected to be reported at a major medical conference in the second quarter of this year.

About InterMune

InterMune is a biotechnology company focused on the research, development and commercialization of innovative therapies in pulmonology and hepatology. InterMune has a pipeline portfolio addressing idiopathic pulmonary fibrosis (IPF) and hepatitis C virus (HCV) infections. The pulmonology portfolio includes the Phase 3 program, CAPACITY, which is evaluating pirfenidone as a possible therapeutic candidate for the treatment of patients with IPF and a research program focused on small molecules for pulmonary disease. The hepatology portfolio includes the HCV protease inhibitor compound ITMN-191 (referred to as R7227 at Roche) in Phase 1b, a second-generation HCV protease inhibitor research program, and a research program evaluating new targets in hepatology.

For additional information about InterMune and its R&D pipeline, please visit www.intermune.com.