Gilead’s research and development program identifies and evaluates investigational compounds that show potential to advance the treatment of life-threatening diseases in areas of unmet medical need. Safety and efficacy of the following compounds have not been established.

Gilead is working to develop next-generation HIV therapies for all individuals who live with the disease, regardless of treatment status or age. Our focus on advancing treatment options resulted in the development of the investigational agent tenofovir alafenamide (TAF), a novel form of the active ingredient in Viread® (tenofovir disoproxil fumarate, or TDF). We believe that TAF-containing regimens have the potential to help appropriate HIV patients who face life-long antiretroviral therapy.

In November 2015 the Food and Drug Administration (FDA) approved Genvoya® (elvitegravir 150 mg/cobicistat 150 mg/emtricitabine 200 mg/tenofovir alafenamide 10 mg or E/C/F/TAF) for the treatment of HIV-1 infection. Genvoya is the first TAF-based regimen to receive FDA approval.

Genvoya was studied in a Phase 3 HIV clinical program in more than 3,500 patients across 21 countries, including treatment-naïve, virologically suppressed, renally impaired and adolescent patients. The approval was supported by 48-week data from two Phase 3 double-blind studies (Studies 104 and 111) among 1,733 treatment-naïve patients in which the regimen met its primary objective of non-inferiority compared to Stribild® (elvitegravir 150 mg, cobicistat 150 mg, emtricitabine 200 mg and tenofovir disoproxil fumarate 300 mg or E/C/F/TDF). In the combined analysis of the studies, 92.4 percent of Genvoya patients and 90.4 percent of Stribild patients had HIV-1 RNA levels less than 50 copies/mL at Week 48. Tests of certain renal and bone laboratory parameters also favored Genvoya over Stribild.

In addition to E/C/F/TAF, two other TAF-based HIV treatments are currently under FDA review: an investigational combination of emtricitabine and TAF (F/TAF) - a potential new HIV treatment “backbone” to be used in combination with other antiretroviral medicines - and R/F/TAF, which is an investigational STR combining F/TAF plus Janssen’s rilpivirine. Janssen is also developing D/C/F/TAF, an investigational STR containing Janssen’s darunavir in combination with cobicistat and F/TAF, which if approved would be the first protease inhibitor-containing STR.

HIV / AIDS

Phase 1
Phase 2
Phase 3

Bictegravir/F/TAF (non-boosted integrase inhibitor/emtricitabine/tenofovir alafenamide)
Potential Indication: HIV/AIDS 

GS-9620 (TLR-7 agonist)
Potential Indication: HIV/AIDS 

More than half a billion people worldwide are infected with chronic hepatitis C virus (HCV) or hepatitis B virus (HBV), both of which over time play a primary role in the development of liver damage and liver failure.

Sovaldi® (sofosbuvir), a once-daily oral treatment used in combination with other antiviral medicines for treating chronic HCV infection, provides an important treatment option for many patients. In 2014, Harvoni® (ledipasvir/sofosbuvir) was approved, becoming the first once-daily single tablet regimen (STR) for the treatment of chronic hepatitis C (CHC) genotype 1 adult patients – the most prevalent genotype in the U.S. Harvoni represents a significant medical advancement because it is a simple regimen that eliminates the need for interferon and ribavirin while providing high cure rates in 12 weeks for most patients and as little as eight weeks for certain subgroups of treatment-naïve patients.

Gilead is also developing an investigational pan-genotypic STR that has the potential to effectively treat chronic HCV patients, regardless of HCV genotype. Investigational development programs are also underway that focus on other non-viral liver diseases such as nonalcoholic steatohepatitis, primary sclerosing cholangitis and liver fibrosis.

Viread® (tenofovir disoproxil fumarate), available for the treatment of chronic HBV infection, provides an option to help manage this chronic disease. For most patients, however, life-long therapy is required. Viread has demonstrated efficacy for chronic HBV sufferers, however, Gilead’s ultimate goal is to offer these patients a cure. Because the biology of HBV infection differs from that of HCV, developing a cure for HBV might require an approach that necessitates multiple drugs to inhibit viral replication and eliminate HBV DNA from all infected liver cells. Several clinical studies with differing approaches are ongoing to investigate this strategy.

Liver Diseases

Phase 1
Phase 2
Phase 3

TAF (nucleotide reverse transcriptase inhibitor)
Potential Indication: Chronic HBV infection

U.S. and EU Regulatory Submission

Sofosbuvir, velpatasvir and voxilaprevir (pan-genotypic NS3 protease inhibitor)
Potential indication: Chronic HCV infection

GS-4774 (Tarmogen T cell immunity stimulator)
Potential Indication: Chronic HBV infection

GS-9620 (TLR-7 agonist)
Potential Indication: Chronic HBV infection

Simtuzumab (monoclonal antibody)
Potential Indication: NASH

Simtuzumab (monoclonal antibody)
Potential Indication: Primary Sclerosing Cholangitis

GS-4997 (ASK-1 inhibitor)
Potential Indication: NASH

GS-4997 (ASK-1 inhibitor) with or without Simtuzumab (monoclonal antibody)
Potential Indication: NASH

GS-9674 (FXR agonist)
Potential Indication: NASH

GS-0976 (ACC Inhibitor)
Potential Indication: NASH

Zydelig® (idelalisib), introduced in 2014, is a first-in-class PI3K delta inhibitor that offers appropriate patients with relapsed chronic lymphocytic leukemia (CLL), follicular lymphoma or small lymphocytic lymphoma, an important option for managing their disease.

Gilead’s portfolio of investigational targeted cancer therapies includes small molecules directed at multiple signaling pathways associated with B-cell malignancies, myelofibrosis and solid tumors – PI3K delta, Syk, JAK and BTK. In addition, an investigational anti-MMP9 antibody is under evaluation in gastric cancer and other solid tumors.

Hematology / Oncology

Phase 1
Phase 2
Phase 3

Idelalisib (PI3K delta inhibitor)
Potential Indication: Relapsed Refractory CLL

Momelotinib (JAK inhibitor)
Potential Indication: Myelofibrosis

GS-5745 (MMP9 mAb inhibitor)
Potential Indication: Gastric Cancer

Entospletinib (Syk inhibitor)
Potential Indication: Hematological Malignancies

Entospletinib (Syk inhibitor)
Potential Indication: Acute Myeloid Leukemia

GS-5745 (MMP9 mAb inhibitor)
Potential Indication: Solid Tumors

GS-4059 (BTK inhibitor)
Potential Indication: B-cell malignancies

GS-5829 (BET inhibitor)
Potential Indication: Solid Tumors

Gilead continues to focus on treatment options for people living with serious cardiovascular diseases. This includes continued progress surrounding the cardiac late sodium current, and the role of this therapeutic target in life-threatening cardiovascular disorders.

Eleclazine, an investigational compound that selectively inhibits the late sodium current, is being evaluated in Phase 2 and 3 studies for life-threatening heart diseases, including long QT-3 syndrome, hypertrophic cardiomyopathy and ventricular tachycardia/ventricular fibrillation.

Additionally, Gilead continues to develop new therapeutic options for people living with pulmonary arterial hypertension (PAH). Gilead scientists are currently advancing a research program aimed at developing a small molecule inhibitor of apoptosis-signal regulating kinase 1 (ASK1). Gilead’s research efforts have led to the discovery of a selective inhibitor of ASK1, which is currently being evaluated in Phase 2 clinical trials for PAH and for other diseases associated with increased oxidative stress.

Cardiovascular

Phase 1
Phase 2
Phase 3

Eleclazine (late sodium current inhibitor)
Potential indication: Long QT-3 Syndrome

Eleclazine (late sodium current inhibitor)
Potential indication: Hypertrophic Cardiomyopathy 

Eleclazine (late sodium current inhibitor)
Potential Indication: Ventricular Tachycardia/Ventricular Fibrillation

GS-4997 (ASK-1 inhibitor)
Potential Indication: Pulmonary Arterial Hypertension

Cystic fibrosis (CF) is a life-threatening genetic condition that mainly affects the lungs and digestive track. Cayston®, an inhaled antibiotic approved in 2010, treats Pseudomonas aeruginosa, a bacterial lung infection that is a primary cause of sickness and hospitalizations in patients with CF. Cayston is included in CF treatment guidelines and provides patients with an effective option for managing their condition.

There is no effective therapy for respiratory syncytial virus (RSV), which accounts for more than 300,000 hospitalizations each year in the United States in infants and adults. In 2014, Gilead reported promising Phase 2a data from a clinical study for an investigational therapy to treat RSV infection, and based on these data in healthy adults, additional studies in a variety of RSV-infected populations are underway, including bone marrow transplant patients and hospitalized adults with upper or lower respiratory tract RSV infection.

Patients with diabetes often develop injury to the kidney that can lead to loss of kidney function. GS-4997 is thought to block a pathway that causes inflammation and scarring, and the investigational agent is being studied in diabetics with kidney damage in hopes of slowing the progression of disease. Additionally, GS-5745 is an investigational agent being studied in inflammatory diseases that involve several different organ systems, including ulcerative colitis, Crohn’s disease, rheumatoid arthritis and lung diseases.

Inflammation / Respiratory

Phase 1
Phase 2
Phase 3

Entospletinib (Syk inhibitor)
Potential Indication: Chronic Graft Versus Host Disease 

Presatovir (fusion inhibitor)
Potential Indication: Respiratory Syncytial Virus 

Filgotinib (JAK1 inhibitor)
Potential Indication: Rheumatoid Arthritis

Filgotinib (JAK1 inhibitor)
Potential Indication: Crohn's Disease

GS-5745 (MMP9 mAb inhibitor)
Potential Indication: Crohn’s Disease

GS-5745 (MMP9 mAb inhibitor)
Potential Indication: Rheumatoid Arthritis

GS-9876 (Syk inhibitor)
Potential Indication: Rheumatoid Arthritis

Gilead’s research and development program identifies and evaluates investigational compounds that show potential to advance the treatment of life-threatening diseases in areas of unmet medical need. Safety and efficacy of the following compounds have not been established.

Other

Phase 1
Phase 2
Phase 3

GS-4997 (ASK-1 inhibitor)
Potential Indication: Diabetic Nephropathy

GS-5734 (Nuc inhibitor)
Potential indication: Ebola Virus Infection