Press Release: Human Genome Sciences Says Antiviral Drug Shows Positive Results

Human Genome Sciences Says Antiviral Drug Shows Positive Results ROCKVILLE, Md., Feb. 27 -- Human Genome Sciences, Inc. today announced interim results at Week 12 following the completion of therapy in a Phase 2b clinical trial of Albuferon(R) (albinterferon alfa-2b) in combination with ribavirin in patients with genotype 1 chronic hepatitis C (HCV) who are naive to interferon alpha-based treatment regimens. A presentation of the full interim data will take place on April 14, 2007, in Barcelona at the 42nd Annual Meeting of the European Association for the Study of the Liver (EASL). (Logo: http://www.newscom.com/cgi-bin/prnh/20010612/HGSLOGO ) "The results suggest that Albuferon may offer comparable or improved efficacy versus Pegasys, with half the injections and the potential for less impairment of health-related quality of life," said David C. Stump, M.D., Executive Vice President, Research and Development, HGS. "These data provide further support for the design of our recently initiated Albuferon Phase 3 development program." The interim results of the Phase 2b trial at Week 12 following the completion of therapy include the following findings: -- The treatment group receiving Albuferon 900-mcg doses every two weeks achieved a higher rate of sustained virologic response at 12 weeks following completion of therapy (SVR12), and more favorable health- related quality-of-life scores, than the Pegasys treatment group. -- Among treatment-adherent patients, 73% of those in the groups receiving Albuferon every two weeks achieved SVR12, versus 63% for patients receiving Pegasys once a week. -- Lower relapse rates were observed among treatment-adherent patients for all Albuferon treatment groups than was observed in the Pegasys treatment group. -- In heavier patients (>75 kg) who were treatment-adherent, SVR12 was maintained in all Albuferon treatment groups, but declined in the Pegasys treatment group. -- The percentage of patients achieving SVR12 in the treatment group receiving 1200-mcg doses of Albuferon every four weeks was comparable to that observed in the group receiving Pegasys once a week, supporting further evaluation of Albuferon treatment with monthly administration. "SVR12 rates were highest and quality-of-life scores were most favorable in the treatment group receiving 900 micrograms of Albuferon every two weeks," said Dr. Stump. "We note that among treatment-adherent patients, both doses of Albuferon administered every two weeks produced a higher rate of SVR12 than was observed in the Pegasys treatment group. Our recently initiated Albuferon Phase 3 program is evaluating both 900-microgram and 1200-microgram doses in a much larger patient population. In addition, the treatment group receiving 1200 micrograms of Albuferon every four weeks performed well, lending strong support to our plan for further evaluation of monthly dosing. We look forward to the initiation by Novartis of a Phase 2b study with this objective later this year." An abstract of the complete presentation of interim results to be made at EASL in April -- entitled "Antiviral Response at Week 12 Following Completion of Treatment with Albinterferon Alfa-2b in Patients with Genotype 1, IFN- naive, Chronic Hepatitis C Infection" (Zeuzem S, Benhamou Y, Bain V, McHutchison J, et al) -- will soon be published on the website of the European Association for the Study of the Liver (EASL) at http://www.easl.ch. Interim data are available through Week 12 following completion of 48 weeks of therapy for 458 patients who were enrolled in the randomized, open-label, multi- center, active-controlled, dose-ranging trial. The study was conducted in Australia, Canada, Czech Republic, France, Germany, Israel, Poland and Romania. Patients were randomized into four treatment groups, three of which received subcutaneously administered Albuferon (900 mcg every two weeks, 1200 mcg every two weeks, and 1200 mcg every four weeks). The fourth treatment group serves as the active control group and received 180-mcg doses of subcutaneously administered peginterferon alfa-2a (Pegasys) once a week. All patients received weight-based oral ribavirin daily. The primary efficacy endpoint is sustained virologic response (SVR), defined as undetectable viral load (HCV RNA80% adherent to therapy) in the groups receiving Albuferon every two weeks, 73.8% in the 900-mcg dose cohort and 72.0% in the 1200-mcg dose cohort achieved SVR12, versus 63.0% for patients receiving Pegasys once a week. Among heavier patients (>75 kg) who were treatment-adherent, SVR12 rates were generally maintained for all Albuferon treatment groups, while declining in the Pegasys group. Lower relapse rates among treatment-adherent patients were observed for all Albuferon treatment groups. The lowest rate of relapse among treatment-adherent patients was observed in the group receiving 900-mcg Albuferon every two weeks -- 13.0%, versus 29.7% for the Pegasys treatment group. The rate of discontinuations due to adverse events were: 9.3% in the group receiving 900-mcg Albuferon every two weeks; 19.1% in the group receiving 1200-mcg Albuferon every two weeks; 12.1% in the group receiving 1200-mcg Albuferon every four weeks; and 6.1% in the group receiving 180-mcg Pegasys once a week. Hematologic reductions were lowest in the group receiving 1200-mcg Albuferon every four weeks, and were comparable across other treatment groups. Health-related quality of life as measured by SF-36 was most favorable for the treatment group receiving 900-mcg Albuferon administered every two weeks. "Of note, only 29% of the patients who discontinued due to adverse events in the treatment group receiving 1200 micrograms of Albuferon every two weeks had an attempt at dose reduction prior to discontinuation," said Dr. Stump. "In the Albuferon Phase 3 trials, we will strongly encourage dose titration to ensure tolerability and maximize the therapeutic benefit of the robust early antiviral response offered by the 1200-microgram dose on a two-week administration schedule." About Albuferon Albuferon is a novel, long-acting form of interferon alpha, which was created by HGS using the Company's proprietary albumin fusion technology. Albuferon results from the genetic fusion of human albumin and interferon alpha. Human albumin is the most prevalent naturally occurring blood protein in the human circulatory system, persisting in circulation in the body for over twenty days. Research has shown that genetic fusion of therapeutic proteins to human albumin decreases clearance and prolongs the half-life of the proteins. Recombinant interferon alpha is approved for the treatment of hepatitis C, hepatitis B and a broad range of cancers. Albuferon is being developed by HGS and Novartis under an exclusive worldwide development and commercialization agreement entered into in June 2006. Under the agreement, HGS and Novartis will co-commercialize Albuferon in the United States, and will share clinical development costs, U.S. commercialization costs and U.S. profits equally. Novartis will be responsible for commercialization in the rest of the world and will pay HGS a royalty on those sales. Clinical development, commercial milestone and other payments to HGS could total as much as $507.5 million, including a $45 million upfront payment and a $47.5 million payment received upon dosing of the first patient in a Phase 3 trial. About Hepatitis C Hepatitis C is an inflammation of the liver caused by the hepatitis C virus. It is estimated that as many as 170 million people worldwide are infected with hepatitis C virus. This includes nearly four million people in the United States. When detectable levels of the hepatitis C virus in the blood persist for at least six months, a person is diagnosed as having chronic hepatitis C. The hepatitis C virus can cause serious liver disease in a significant proportion of infected individuals, leading to cirrhosis, primary liver cancer, and even death. Conference Call HGS management will hold a conference call to discuss this announcement, as well as the Company's fourth quarter and full-year 2006 results, today at 5:00 PM Eastern time. Investors may listen to the call by dialing 800-263-8506 or 719-457-2681, passcode 1549825, five to ten minutes before the start of the call. A replay of the conference call will be available within a few hours after the call ends. Investors may listen to the replay by dialing 888-203-1112 or 719-457-0820, confirmation code 1549825. Today's conference call also will be webcast and can be accessed at http://www.hgsi.com. Investors interested in listening to the live webcast should log on before the conference call begins in order to download any software required. Both the audio replay and the archive of the conference call webcast will remain available for several days. About Human Genome Sciences The mission of HGS is to apply great science and great medicine to bring innovative drugs to patients with unmet medical needs. The HGS clinical development pipeline includes novel drugs to treat hepatitis C, lupus, anthrax disease, cancer, rheumatoid arthritis and HIV/AIDS. The Company's primary focus is rapid progress toward the commercialization of its two lead compounds, Albuferon(R) for hepatitis C, and LymphoStat-B(R) for lupus. Phase 3 clinical trials of both compounds are now underway. In June 2006, HGS announced that the U.S. Government exercised its option under an existing contract to purchase 20,000 doses of ABthrax(TM) for the treatment of anthrax disease. Other HGS drugs in clinical development include three TRAIL receptor antibodies for the treatment of hematopoietic and solid malignancies, in addition to an antibody to the CCR5 receptor for the treatment of HIV/AIDS. For more information about HGS, please visit the Company's web site at http://www.hgsi.com. For more information about Albuferon, visit http://www.hgsi.com/products/albuferon.html. Health professionals or patients interested in LymphoStat-B clinical trials or other studies involving HGS products may inquire via the Contact Us section of the company's web site, http://www.hgsi.com/products/request.html, or by calling us at (301) 610-5790, extension 3550. HGS, Human Genome Sciences, ABthrax, Albuferon, BLyS and LymphoStat-B are trademarks of Human Genome Sciences, Inc. Safe Harbor Statement This announcement contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. The forward-looking statements are based on Human Genome Sciences' current intent, belief and expectations. These statements are not guarantees of future performance and are subject to certain risks and uncertainties that are difficult to predict. Actual results may differ materially from these forward-looking statements because of the Company's unproven business model, its dependence on new technologies, the uncertainty and timing of clinical trials, the Company's ability to develop and commercialize products, its dependence on collaborators for services and revenue, its substantial indebtedness and lease obligations, its changing requirements and costs associated with planned facilities and clinical trials, intense competition, the uncertainty of patent and intellectual property protection, the Company's dependence on key management and key suppliers, the uncertainty of regulation of products, the impact of future alliances or transactions and other risks described in the Company's filings with the Securities and Exchange Commission. In addition, the Company will continue to face risks related to animal and human testing, to the manufacture of ABthrax and to FDA concurrence that ABthrax meets the requirements of the ABthrax contract. If the Company is unable to meet the product requirements associated with the ABthrax contract, the U.S. Government will not be required to reimburse the Company for the costs incurred or to purchase any ABthrax doses. Existing and prospective investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of today's date. Human Genome Sciences undertakes no obligation to update or revise the information contained in this announcement whether as a result of new information, future events or circumstances or otherwise. Photo: http://www.newscom.com/cgi-bin/prnh/20010612/HGSLOGOAP Archive: http://photoarchive.ap.orgPRN Photo Desk [email protected] Genome Sciences, Inc. CONTACT: Jerry Parrott, Vice President, Corporate Communications,+1-301-315-2777, or Kate de Santis, Director, Investor Relations,+1-301-251-6003, both of Human Genome Sciences, Inc. Web site: http://www.hgsi.com/http://www.easl.ch/