Gilead Announces Phase 3 Data Showing That the Fixed-Dose Combination of Ledipasvir/Sofosbuvir Achieved 100 Percent Sustained Virologic Response (SVR12) Among Patients with Chronic Hepatitis C in Japan

-- Interferon- and Ribavirin-Free Therapy Effective against Genotype 1 HCV, Japan’s Most Prevalent Strain of the Disease --

-- Japanese Regulatory Submission for Ledipasvir/Sofosbuvir Anticipated by Year End --

FOSTER CITY, Calif.--(BUSINESS WIRE)--Jun. 15, 2014-- Gilead Sciences, Inc. (Nasdaq: GILD) today announced topline results from a Phase 3 clinical trial (GS-US-337-0113) in Japan evaluating the investigational once-daily fixed-dose combination of the NS5A inhibitor ledipasvir (LDV) 90 mg and the nucleotide analog polymerase inhibitor sofosbuvir (SOF) 400 mg, with and without ribavirin (RBV), for the treatment of genotype 1 chronic hepatitis C virus (HCV) infection. Among patients receiving 12 weeks of LDV/SOF without RBV, 100 percent (n=83/83) of treatment-naïve and 100 percent (n=88/88) of treatment-experienced patients achieved a sustained virologic response 12 weeks after completing therapy (SVR12). Among patients receiving LDV/SOF plus RBV, 96 percent (n=80/83) of treatment-naïve and 100 percent of treatment-experienced patients (n=87/87) achieved SVR12. Across all arms of the study, patients with cirrhosis achieved a 99 percent (n=75/76) SVR12. The study met its primary endpoint of superiority compared to a predefined historical SVR12 rate. Patients who achieve SVR12 are considered cured of HCV infection.

Genotype 1 is the most common strain of HCV in Japan, accounting for approximately 70 percent of the more than one million people chronically infected with the disease. The majority of these infections are due to HCV genotype 1b. Current treatment options for genotype 1 HCV infection involve up to 48 weeks of therapy with pegylated interferon injections, RBV tablets and other oral medicines, which may not be suitable for certain patients.

“The cure rates observed with LDV/SOF in this study are impressive because they were achieved without the need for interferon or ribavirin, both of which involve more complex dosing requirements and may be associated with significant side effects,” said Norbert Bischofberger, PhD, Gilead’s Executive Vice President of Research and Development and Chief Scientific Officer. “These results suggest that a once-daily LDV/SOF tablet has the potential to be an efficacious and well-tolerated regimen for many HCV patients in Japan.”

In the study, 341 patients with genotype 1 HCV infection were randomized (1:1) to receive 12 weeks of all-oral therapy with LDV/SOF, with or without RBV. Of these, 166 patients were treatment-naïve, 175 were treatment-experienced and 76 had compensated cirrhosis. The intent-to-treat SVR12 rates in the study are summarized in the table below:

Overall, 338/341 patients (99 percent) in Study GS-US-337-0113 achieved SVR12. Of the three patients who failed to achieve SVR12, one patient relapsed after discontinuation of therapy, one patient discontinued therapy after one week of treatment due to rash and one patient died during the study.

Fewer adverse events were observed in the RBV-free arms compared to the RBV-containing arms in the study, most notably with regard to anemia, which was observed in 14 percent of patients taking LDV/SOF plus RBV compared to 2 percent of patients receiving LDV/SOF alone. Adverse events observed with LDV/SOF without RBV were generally mild and included nasopharyngitis (28 percent), headache (6 percent) and malaise (5 percent). Among those taking LDV/SOF plus RBV, in addition to anemia, the most common adverse events were nasopharyngitis (22 percent), pruritus (8 percent), rash (8 percent), headache (8 percent), stomatitis (6 percent), nausea (5 percent) and malaise (5 percent). No patients taking LDV/SOF and two patients taking LDV/SOF plus RBV discontinued treatment due to treatment-emergent adverse events. Full study results will be presented at a future scientific meeting.

Based on these data, Gilead plans to submit a New Drug Application for the LDV/SOF fixed-dose combination with the Japanese Pharmaceutical and Medical Devices Agency (PMDA) by the end of 2014. The product is currently under regulatory review in the United States and European Union.

On April 2, 2014, Gilead announced topline results from another Phase 3 study in Japan evaluating SOF as a single agent in combination with RBV for the treatment of genotype 2 HCV infection. The company plans to file for approval of SOF with the PMDA by mid-2014. SOF as a single agent has been approved by regulatory authorities in the United States, European Union and Canada under the tradename Sovaldi^®.

LDV/SOF and SOF are investigational products in Japan and their safety and efficacy have not yet been established.

About Gilead Sciences

Gilead Sciences is a biopharmaceutical company that discovers, develops and commercializes innovative therapeutics in areas of unmet medical need. The company’s mission is to advance the care of patients suffering from life-threatening diseases worldwide. Headquartered in Foster City, California, Gilead has operations in North and South America, Europe and Asia Pacific.

Forward-Looking Statement

This press release includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks, uncertainties and other factors, including the possibility of unfavorable results from additional clinical trials involving SOF or the LDV/SOF fixed-dose combination in Japan and the possibility that the company may not file for regulatory approval of SOF as a single agent or the LDV/SOF fixed-dose combination in Japan in the currently anticipated timelines. Further, the PDMA and regulatory authorities in the United States and the European Union may not approve the LDV/SOF fixed-dose combination and the PMDA may not approve SOF as a standalone agent in Japan, and any marketing approvals, if granted, may have significant limitations on their use. These risks, uncertainties and other factors could cause actual results to differ materially from those referred to in the forward-looking statements. The reader is cautioned not to rely on these forward-looking statements. These and other risks are described in detail in Gilead’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2014, as filed with the U.S. Securities and Exchange Commission. All forward-looking statements are based on information currently available to Gilead, and Gilead assumes no obligation to update any such forward-looking statements.

U.S. full prescribing information for Sovaldi is available at www.gilead.com.

Sovaldi is a registered trademark of Gilead Sciences, Inc.

For more information on Gilead Sciences, please visit the company’s website at www.gilead.com, follow Gilead on Twitter (@GileadSciences) or call Gilead Public Affairs at 1-800-GILEAD-5 or 1-650-574-3000.

Source: Gilead Sciences, Inc.

Gilead Sciences, Inc.Investors:Patrick O’Brien, 650-522-1936orMedia:Cara Miller, 650-522-1616