KITE’S AUTOLOGOUS ANTI-CD19-TRANSDUCED CD3+ CELLS DEMONSTRATE HIGH REMISSION RATES IN ADULT PATIENTS WITH RELAPSED/REFRACTORY B CELL ACUTE LYMPHOBLASTIC LEUKAEMIA

KITE’S  AUTOLOGOUS  ANTI-CD19-TRANSDUCED  CD3+  CELLS  DEMONSTRATE  HIGH  REMISSION  RATES  IN  ADULT  PATIENTS  WITH  RELAPSED/REFRACTORY  B CELL  ACUTE  LYMPHOBLASTIC  LEUKAEMIA

--  71% of Adult Patients in Phase 2 ZUMA-3 Study Achieved Complete Remission or Complete Remission with Incomplete Haematological Recovery  --

Stockley Park, UK – 11 June 2021 – Kite, a Gilead Company, today announced that results from the primary analysis of ZUMA-3, a global, multicentre, single-arm, open-label Phase 1/2 study evaluating autologous anti-CD19-transduced CD3+ cells (formerly KTE-X19, Tecartus^®) in adult patients with relapsed/refractory B cell acute lymphoblastic leukaemia (ALL) were presented at the 26^th Virtual Annual Meeting of the European Hematology Association (EHA2021) from the 9-17 June (Abstract #S117),¹ and also published in The Lancet.²

The use of autologous anti-CD19-transduced CD3+ cells for the treatment of adult patients with relapsed/refractory ALL remains investigational.

“Outcomes in adults with acute lymphoblastic leukemia are poor relative to what is observed in children, with less than half of people over 20 years of age expected to survive the illness. It is on this background that CAR T-cell therapy with autologous anti-CD19-transduced CD3+ cells was tested in adults with relapsed B-ALL in ZUMA-3,” said Bijal Shah, MD, ZUMA-3 investigator and medical oncologist, Moffitt Cancer Center, Tampa, Florida. “In this international, multicenter study, we observed an overall complete remission rate of 71%. Importantly, the majority of these remissions were associated with undetectable minimal residual disease.”

In the pivotal Phase 2 portion of the trial, 71 patients with relapsed/refractory disease were enrolled. Among treated patients (n=55), 47% had received three or more prior therapies. At a median follow-up of 16.4 months, 71% of treated patients achieved overall complete remission, defined as complete remission (CR) or CR with incomplete haematological recovery (CRi), with 31% in ongoing remission at data cut-off. In this trial, 97% of those responders had deep molecular remission, with undetectable minimal residual disease (MRD). Median overall survival (OS) among all responders was not reached. Among 25 patients with prior blinatumomab treatment, the CR/CRi rate was 60%. Among all treated patients, median duration of remission (DOR) was 12.8 months, relapse-free survival (RFS) was 11.6 months, and OS was 18.2 months.¹

Grade ≥3 adverse events occurred in 95% of patients, with anaemia (49%) and pyrexia (36%) most frequently reported. Grade ≥3 cytokine release syndrome (CRS) and neurologic events occurred in 24% and 25% of patients, respectively, and were generally reversed with treatment. Two Grade 5 treatment–related events occurred (1 brain herniation and 1 case of septic shock).²

A separate health-related quality of life analysis presented at EHA2021 found that the majority of patients enrolled in ZUMA-3 experienced improved or stable health-related quality of life up to 12 months after CAR T cell therapy, as measured by EQ-5D score. Mean EQ-5D Index scores were 0.82 at screening with the highest score at Month 12 (0.91). Results should be interpreted with caution due to missing follow-up data for some patients and small sample size.³

In addition, an analysis of relapsed/refractory ALL studies found a high degree of variance in some of the definitions used for the common efficacy endpoints in different clinical trials. The endpoint most consistently defined was complete remission, suggesting that treatment response outcome measures for historical control studies should be based on complete remission alone.⁴

About Kite’s Autologous Anti-CD19-transduced CD3+ Cells (Formerly KTE-X19)

In December 2020, the European Commission granted conditional Marketing Authorisation for autologous anti-CD19-transduced CD3+ cells, the first CAR T cell therapy approved in Europe for adult patients with relapsed or refractory mantle cell lymphoma after two or more lines of systemic therapy including a Bruton’s tyrosine kinase (BTK) inhibitor.⁵

About ZUMA-3

ZUMA-3 is an ongoing international multicentre registrational Phase 1/2 study in adult patients (≥18 years old) with ALL whose disease is refractory to or has relapsed following standard systemic therapy with remission of 12 months or less, after two or more lines of systemic therapy or after allogeneic stem cell transplantation. The objectives of the study are to evaluate the safety and efficacy of autologous anti-CD19-transduced CD3+ cells in this patient population.¹

About Acute Lymphoblastic Leukaemia

Acute lymphoblastic leukaemia (ALL) is an aggressive blood cancer which can also involve the lymph nodes, spleen, liver, central nervous system, and other organs. Globally over 64,000 people are diagnosed with ALL each year.⁶ While ALL incidence rates are four times higher in children than adults, survival is particularly poor among adults.⁷

About Kite 

Kite, a Gilead Company, is a global biopharmaceutical company based in Santa Monica, California, with commercial manufacturing operations in North America and Europe. Kite is engaged in the development of innovative cancer immunotherapies. The company is focused on chimeric antigen receptor and T cell receptor engineered cell therapies. 

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.

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 ongoing and additional clinical studies involving Tecartus and the possibility that Kite may be unable to initiate or complete one or more of such studies in the currently anticipated timelines or at all; Kite’s ability to receive regulatory approvals in a timely manner or at all, and any marketing approvals if granted, may have significant limitations on its use. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. 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, uncertainties and other factors are described in detail in Gilead’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2021, as filed with the U.S. Securities and Exchange Commission. All forward-looking statements are based on information currently available to Gilead and Kite, and Gilead and Kite assume no obligation to update any such forward-looking statements.