GILEAD ANNOUNCES NEW DATA REINFORCING CLINICAL BENEFITS OF ITS ANTIVIRAL TREATMENTS AMONG PEOPLE LIVING WITH HEPATITIS B AND C IN ASIA (APASL 2022)

Studies show potential improvement in risk of liver cancer in chronic hepatitis B patients after long-term antiviral treatment

Improved renal and bone parameters with tenofovir alafenamide (TAF) compared to tenofovir disoproxil fumarate (TDF) across multiple chronic hepatitis B patient types

Data on hepatitis C show benefit of sofosbuvir-based regimens

SINGAPORE,March 30,2022 -- Gilead Sciences today announced data from multiple studies highlighting the clinical benefit and differentiation of its hepatitis treatments,as well as Gilead's ongoing commitment to liver research to advance the elimination of viral hepatitis in Asia. The data are being presented at the 31st Conference of the Asian Pacific Association for the Study of the Liver (APASL 2022),March 30 – April 3,2022 in Seoul,South Korea.

"The clinical data from our studies reinforce the well-established efficacy and safety profiles of our treatments and the potential clinical benefit to people living withhepatitis B and C. These encouraging data can further support healthcare providers in making the appropriate treatment choice for hepatitis patients in Asia." saidBetty Chiang,Vice President of Medical Affairs,International,Gilead Sciences.

Data from three tenofovir (TFV)-based studies for the treatment of hepatitis B (HBV) presented at the conference showed that at treatment initiation few patients at low risk of hepatocellular carcinoma (HCC) progressed to higher risk,while many medium- or high-risk patients improved to lower risk of HCC after long-term TFV treatment.

Data from a Phase 2 study of TFV disoproxil fumarate (TDF) vs. TDF/emtricitabine (FTC) in immune-tolerant (IT) patients and two Phase 3 studies,comparing tenofovir alafenamide (TAF) vs. TDF in immune-active (IA) patients were used to generate HCC risk scores by using Modified PAGE-B (mPAGE-B),a tool to predict 5-year HCC risk (low-risk [0-≤8],medium-risk [9-12],and high-risk [≥13]).

Of126 IT patients,106 (84%),19 (15%) and 1 (0.8%) were low‑,medium‑,or high‑risk,respectively at baseline. At Week 192,the majority remained categorically unchanged or improved. No IT patients developed HCC. Of 1,631 IA patients (1,092 TAF; 539 TDF->TAF),901 (55%),588 (36%),and 142 (9%) were low-,medium-,or high-risk,respectively at baseline. At Week 240,the majority remained unchanged or improved; only 22 (2%) patients shifted to higher risk. Overall,22 HCC cases developed (0.2%,1.2%,and 9.2% in the low-,and high-risk groups at baseline).

Additional data presented at the conference provides an assessment of the bone and renal safety profile of TAF across Gilead's TAF HBV clinical development program. Data from 1,911 patients treated with TAF or TDF were analysed andacross multiple HBV patient types,including those at higher risk of TDF-associated bone and/or renal toxicity. Stable or improved bone and renal parameters were observed with TAF treatment compared to TDF treatment.

In hepatitis C,a Phase 3b study looking at treatment-naïve and treatment-experienced chronic hepatitis C(CHC) patients in Korea showed that treatment with sofosbuvir/velpatasvir and sofosbuvir/velpatasvir/voxilaprevir achieved high sustained virological response with no on-treatment virologic failure or treatment-related serious adverse events. In another study evaluating potential drug-drug interactions (DDIs) in Korean CHC patients using widely available direct acting antivirals,sofosbuvir/velpatasvir showed a favourable DDI profile despite the high rates of comorbidity and comedications among the aging trend of the CHC population in Korea.

Abstracts presented at APASL 2022 are as follows:

[OP-0973]

Impact of long-term oral antiviral treatment on hepatocellular carcinoma risk in immune-tolerant (IT) and immune-active (IA) chronic hepatitis B patients (CHB) utilizing modified PAGE-B score

[PP-0978]

Improved bone and renal parameters across multiple chronic HBV (CHB) patient types treated with tenofovir alafenamide (TAF) versus tenofovir disoproxil fumarate (TDF)

[PP-0073]

Comorbidities and prescription patterns among patients with chronic hepatitis C in Korea

[OP-0322]

The efficacy and safety of Sofosbuvir/Velpatasvir and Sofosbuvir/Velpatasvir/Voxilaprevir in HCV infected Korean patients

About Gilead Sciences

Gilead Sciences,Inc. is a biopharmaceutical company that has pursued and achieved breakthroughs in medicine for more than three decades,with the goal of creating a healthier world for all people. The company is committed to advancing innovative medicines to prevent and treat life-threatening diseases,including HIV,viral hepatitis and cancer. Gilead operates in more than 35 countries worldwide,with headquarters in Foster City,California. For more information on Gilead Sciences,please visit the company's website at www.gilead.com.

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.