KENILWORTH, N.J. (Map) - KENILWORTH, N.J., May 15 /PRNewswire-FirstCall/ -- Schering-Plough Corporation (NYSE: SGP), a leader in advancing the science and treatment of chronic hepatitis C virus (HCV) infection, announced today that data from several clinical studies with PEGINTRON(TM) (peginterferon alfa-2b) and REBETOL(R) (ribavirin, USP) combination therapy, as well as boceprevir, the company's investigational oral HCV protease inhibitor, will be presented at the 39th annual Digestive Disease Week (DDW) meeting to be held at the San Diego Convention Center, May 17-22.

Hepatitis C is the most common blood-borne infection in America and the most common form of liver disease, affecting nearly 5 million people in the United States and 200 million people worldwide. It is the leading cause of cirrhosis and liver cancer, and the number one reason for liver transplants in the United States.

Clinical investigators will present findings from several PEGINTRON studies evaluating patient response to therapy at important treatment milestones, an approach that is aimed at individualizing treatment for patients to help improve outcomes. In particular, Schering-Plough is exploring unique treatment strategies for patients with more difficult-to-treat forms of the disease, such as patients who were nonresponders to previous therapy.

Schering-Plough also is exploring novel therapeutic approaches to treating hepatitis C with boceprevir, its investigational oral HCV protease inhibitor currently in Phase II clinical development. The final results of a Phase II dose-finding study of boceprevir with or without ribavirin in patients who were "null" responders to previous peginterferon and ribavirin combination therapy will be presented.

Key Data Presentations at DDW

PEGINTRON

Results from the EPIC3 Program: Platelet Counts Are Strong Predictors of Sustained Viral Response (SVR) in the Retreatment of Previous Interferon/Ribavirin Non-Responders (NR). Poynard, T. et al. Poster S1000, Abstract No. 442673, Sunday, May 18, 8:00 a.m. - 5:00 p.m., Sails Pavilion.

Clearance of HCV at 5 Year Follow-Up for Peginterferon Alfa-2b with or without Ribavirin Is Predicted by Sustained Virologic Response at 24 Weeks Post-Treatment. Lindsay, K. et al. Poster S1001, Abstract No. 443097, Sunday, May 18, 8:00 a.m. - 5:00 p.m., Sails Pavilion.

Sustained Virologic Response and Relapse Rates with Peginterferon Alfa-2b Plus Ribavirin in Clinical Trials Are Comparable to Those in Community-Based Studies. Manns, M. et al. Poster W1004, Abstract No. 441859, Wednesday, May 21, 8:00 a.m. - 5:00 p.m., Sails Pavilion.

Rapid Virologic Response to Peginterferon Alfa and Ribavirin Treatment of Chronic Hepatitis C Predicts Sustained Virologic Response and Relapse. Poordad, F. et al. Poster W1007, Abstract No. 439219, Wednesday, May 21, 8:00 a.m. - 5:00 p.m., Sails Pavilion.

Boceprevir

Role of Interferon Response During Re-Treatment of Null Responders with Boceprevir Combination Therapy: Results of Phase II Trial. Schiff, E. et al. Oral Presentation 162, Abstract No. 442360, Sunday, May 18, 4:30 p.m., Room 6DE.

Schering-Plough Supported CME Symposium

Defining the Course in the Management of HCV: A Case Based Approach Sunday, May 18, 6:30-9:30 p.m., San Diego Marriott Hotel and Marina, Hall 3-6. A world-renowned faculty will present and discuss recent data and how this information may impact clinical management decisions. Among the educational objectives of this program is to define the role of viral clearance as a predictor of HCV treatment response.

About PEGINTRON

In the United States, PEGINTRON is indicated for use alone or with ribavirin for the treatment of chronic hepatitis C in patients with compensated liver disease who have not been previously treated with interferon alpha and who are at least 18 years of age.

Important Safety Information Regarding U.S. Labeling for PEGINTRON and REBETOL

Alpha interferons, including PEGINTRON and INTRON(R) A, may cause or aggravate fatal or life-threatening neuropsychiatric, autoimmune, ischemic, and infectious disorders. Patients should be monitored closely with periodic clinical and laboratory evaluations. Patients with persistently severe or worsening signs or symptoms of these conditions should be withdrawn from therapy. In many, but not all cases, these disorders resolve after stopping PEGINTRON and/or INTRON A therapy.

Use with Ribavirin: Ribavirin may cause birth defects and/or death of the unborn child. Extreme care must be taken to avoid pregnancy in female patients and in female partners of male patients. Ribavirin causes hemolytic anemia. The anemia associated with REBETOL therapy may result in a worsening of cardiac disease. Ribavirin is genotoxic and mutagenic and should be considered a potential carcinogen

Contraindications

PEGINTRON is contraindicated in patients with hypersensitivity to PEGINTRON or any other component of the product, autoimmune hepatitis, and hepatic decompensation (Child-Pugh score greater than 6 [class B and C]) in cirrhotic CHC patients before or during treatment. INTRON A (Interferon alfa-2b, recombinant) for Injection is contraindicated in patients with hypersensitivity to INTRON A or any component of the product, autoimmune hepatitis, and decompensated liver disease. PEGINTRON or INTRON A in combination with REBETOL therapy is additionally contraindicated in patients with hypersensitivity to ribavirin or any other component of the product, women who are pregnant, men whose female partners are pregnant, patients with hemoglobinopathies (e.g., thalassemia major, sickle-cell anemia), and patients with creatinine clearance less than 50 mL/min.

Avoid Pregnancy

REBETOL therapy should not be started until a report of a negative pregnancy test has been obtained immediately prior to planned initiation of therapy. Extreme care must be taken to avoid pregnancy in female patients and in female partners of male patients during therapy and 6 months post- treatment. Patients should use at least two effective forms of contraception and have monthly pregnancy tests during therapy and for 6 months after completion of therapy. A Ribavirin Pregnancy Registry has been established to monitor maternal-fetal outcomes of pregnancies in female patients and female partners of male patients exposed to ribavirin during treatment, and for 6 months following cessation of treatment. Physicians and patients are encouraged to report such cases by calling 1-800-593-2214.

Incidence of Adverse Events

There are no new adverse events specific to PEGINTRON as compared to INTRON A; however, the incidence of some (e.g., injection site reactions, fever, rigors, nausea) were higher. The most common adverse events associated with PEGINTRON were "flu-like" symptoms, occurring in approximately 50% of patients, which may decrease in severity as treatment continues. Application site disorders were common (47%), but all were mild (44%) or moderate (4%) and no patient discontinued, and included injection site inflammation and reaction (i.e., bruise, itchiness, irritation). Injection site pain was reported in 2% of patients receiving PEGINTRON. Alopecia (thinning of the hair) is also often associated with alpha interferons including PEGINTRON.

Psychiatric adverse events, which include insomnia, were common (57%) with PEGINTRON but similar to INTRON A (58%). Depression was most common at 29%. Suicidal behavior including ideation, suicidal attempts, and completed suicides occurred in 1% of patients during or shortly after completing treatment with PEGINTRON.

The following serious or clinically significant adverse events have been reported at a frequency less than 1% with PEGINTRON or interferon alpha: Severe decreases in neutrophil or platelet counts, hypothyroidism, hyperglycemia, hypotension, arrhythmia, ulcerative and hemorrhagic colitis, development or exacerbation of autoimmune disorders including thyroiditis, RA, systemic lupus erythematosus, psoriasis, pulmonary disorders (dyspnea, pulmonary infiltrates, pneumonitis and pneumonia, some resulting in patient deaths), urticaria, angioedema, bronchoconstriction, anaphylaxis, retinal hemorrhages, and cotton wool spots.

In the PEGINTRON/REBETOL combination trial, the incidence of serious adverse events was 17% in the PEGINTRON/REBETOL groups compared to 14% in the INTRON A/ REBETOL group. The incidence of severe adverse events in the PEGINTRON/REBETOL combination therapy trial was 23% in the INTRON A/REBETOL group and 31-34% in the PEGINTRON/REBETOL groups. Dose reductions due to adverse reactions occurred in 42% of patients receiving PEGINTRON (1.5 mcg/kg)/REBETOL and in 34% of those receiving INTRON A/REBETOL.

In a study with weight-based ribavirin, there was a higher rate of anemia among patients in the weight-based dosing group (29%) compared to the flat- dosing group (19%). The majority of these cases were mild and responded to dose reductions. Serious adverse events were similar between the two groups (12%), and discontinuations for adverse events (15% in weight-based dosing and 14% in flat dosing) were also similar. Dose modifications due to adverse events occurred more frequently in the weight-based dosing group (29%) compared to the flat-dosing (23%) group.

Additional Safety Information

Relapse of drug addiction/overdose has occurred in patients on PEGINTRON therapy. Aggressive behavior sometimes directed towards others has occurred in patients with and without a previous psychiatric disorder during PEGINTRON and/or INTRON A treatment and follow-up. If patients develop psychiatric problems, including clinical depression, it is recommended that patients be carefully monitored during treatment and in the 6-month follow-up period. If psychiatric symptoms persist or worsen, or suicidal ideation or aggressive behavior towards others is identified, it is recommended that treatment with PEGINTRON and/or INTRON A be discontinued, and the patient be carefully followed with psychiatric intervention, as appropriate. Cases of encephalopathy have been observed in some patients, usually elderly, treated with higher doses of PEGINTRON and/or INTRON A. Ischemic and hemorrhagic cerebrovascular events have been observed in patients treated with interferon alpha therapies, including PEGINTRON and INTRON A. Dental and periodontal disorders have been reported in patients receiving PEGINTRON or INTRON A in combination with REBETOL therapy.

Please see important full U.S. prescribing information and the Medication Guide for PEGINTRON at www.schering-plough.com.

About Schering-Plough

Schering-Plough is an innovation-driven, science-centered global health care company. Through its own biopharmaceutical research and collaborations with partners, Schering-Plough creates therapies that help save and improve lives around the world. The company applies its research-and-development platform to human prescription and consumer products as well as to animal health products. Schering-Plough's vision is to "Earn Trust, Every Day" with the doctors, patients, customers and other stakeholders served by its colleagues around the world. The company is based in Kenilworth, N.J., and its Web site is www.schering-plough.com.

SCHERING-PLOUGH DISCLOSURE NOTICE: The information in this press release includes certain "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, including statements relating to the potential market for PEGINTRON and REBETOL, and the clinical development and potential for boceprevir. Forward-looking statements relate to expectations or forecasts of future events. Schering-Plough does not assume the obligation to update any forward-looking statement. Many factors could cause actual results to differ materially from Schering-Plough's forward-looking statements, including market forces, economic factors, product availability, patent and other intellectual property protection, current and future branded, generic or over-the-counter competition, the regulatory process, and any developments following regulatory approval, among other uncertainties. For further details about these and other factors that may impact the forward-looking statements, see Schering-Plough's Securities and Exchange Commission filings, including Part I, Item 1A. "Risk Factors" in Schering-Plough's 2007 10-K/A.