On June 1, 2019 IMV Inc. (Nasdaq: IMV; TSX: IMV), a clinical stage immuno-oncology corporation, reported that investigators shared new positive data for its DeCidE1 (DPX-Survivac with low dose Cyclophosphamide and Epacadostat) clinical trial at the 2019 American Society for Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting (Press release, IMV, JUN 1, 2019, View Source [SID1234536848]).

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These new data are from the ongoing Phase 1b/2 trial evaluating the safety and efficacy of IMV’s lead candidate DPX-Survivac and intermittent low-dose cyclophosphamide (CPA), with and without Incyte’s IDO1 enzyme inhibitor epacadostat, in patients with advanced recurrent ovarian cancer. New data from evaluable patients from the phase 2 monotherapy arm of the trial indicated the potential for DPX-Survivac to impact solid tumor growth in hard to treat ovarian cancer patients. Longer-term follow-up from the phase 1b portion of the trial continued to demonstrate that the levels of survivin-specific T cells in the blood of patients – a measure of DPX-Survivac’s novel mechanism of action (MOA) – correlated with durable clinical benefits.

Updated Clinical Data for DeCidE1

In a poster presentation, Janos L. Tanyi, M.D., Ph.D., Assistant Professor of Obstetrics and Gynecology at the Hospital of the University of Pennsylvania, provided an update on the clinical results from the first patients enrolled in the phase 2 monotherapy cohort. Researchers have enrolled 19 of 28 participants to date:

Of seven patients evaluable at data cut-off in the monotherapy arm, five showed signs of treatment benefits, including reduction of target lesions in two patients, while two patients progressed.

Within the group of four patients with low tumor burden – a potential predictor of response – three showed stable diseases including two reductions in tumor burden continuing the positive trend seen in earlier results.

All subjects evaluable for T cell responses (five of five) showed survivin specific T cell activation in the blood, four of five showed a robust response. IHC analysis for tumor infiltration is ongoing

Treatments have been well tolerated.

"We believe that immunotherapy can and should be an integral part of treatment options for hard-to-treat cancers, including solid tumor indications like ovarian cancer in which patients continue to maintain an urgent need for better outcomes," said Frederic Ors, Chief Executive Officer, IMV Inc. "We continue to accumulate evidence of DPX-Survivac’s clinical activity in these patients and are encouraged by the multiple tumor shrinkages and long-lasting responses we have seen to date."

The data also highlighted long-lasting responders from the phase 1b portion of the study with key takeaways as follows:

Prolonged duration of clinical benefits reaching up to more than two years, surpassing the progression-free survival to previous treatments, including platinum-based chemotherapy.

Long-lasting clinical benefits and high levels of survivin specific T cells are associated with long-term treatment;

One subject has received DPX-Survivac for more than 21 months so far. This finding is the longest duration of treatment for DPX-Survivac on record to date.

It is supportive of DPX Survivac’s ability to maintain high levels of survivin-specific T cells in the blood over a prolonged period of time.

About the DeCidE1 Phase 1b/2 Trial

The DeCidE1 study is an open label, uncontrolled phase 1b/2 trial to assess the safety and efficacy of DPX-Survivac and cyclophosphamide with and without epacadostat in individuals with advanced, platinum-sensitive and resistant ovarian cancer. IMV completed enrollment of 53 subjects in the phase 1b cohort in December 2018. Following positive top line data, IMV amended the phase 2 protocol to stop enrollment in the combination arm with epacadostat and evaluate DPX-Survivac monotherapy with CPA in patients with lower tumor burden. As of the May 27, 2019 data cut-off date, 12 subjects have been enrolled in the phase 2 randomized portion of the trial and 7 subjects have been enrolled so far in the monotherapy population with lower baseline tumour burden.

The amended phase 2 cohort of the DECIDE1 trial is targeting enrollment of at least 16 subjects in the population with a lower baseline tumor burden. Enrollment is ongoing at multiple sites in the U.S. and Canada.

About DPX-Survivac

DPX-Survivac is the lead candidate in IMV’s new class of immunotherapies that programs targeted T cells in vivo. It has demonstrated the potential for industry-leading targeted, persistent, and durable T cell activation. IMV believes this mechanism of action (MOA) is key to generating durable solid tumor regressions. DPX-Survivac consists of survivin-based peptides formulated in IMV’s proprietary DPX drug delivery platform. DPX-Survivac is designed to work by eliciting a cytotoxic T cell immune response against cancer cells presenting survivin peptides on their surface.

Survivin, recognized by the National Cancer Institute (NCI) as a promising tumor-associated antigen, is broadly over-expressed in most cancer types, and plays an essential role in antagonizing cell death, supporting tumor-associated angiogenesis, and promoting resistance to anti-cancer therapies. IMV has identified over 15 cancer indications in which the over-expression of survivin can be targeted by DPX-Survivac.

DPX-Survivac has received Fast Track designation from the U.S. Food and Drug Administration (FDA) as maintenance therapy in advanced ovarian cancer, as well as orphan drug designation status from the U.S. FDA and the European Medicines Agency (EMA) in the ovarian cancer indication. It is currently being evaluated in multiple Phase 1b/2 clinical trials.

On June 1, 2019 Daiichi Sankyo Company, Limited (hereafter, Daiichi Sankyo), reported that new data from a pooled analysis of the phase 3 ENLIVEN study and phase 1 extension study showed continued treatment with pexidartinib resulted in an increased tumor response rate in TGCT patients (Press release, Daiichi Sankyo, JUN 1, 2019, https://www.prnewswire.com/news-releases/daiichi-sankyos-pexidartinib-demonstrated-further-improvement-with-continued-treatment-of-tenosynovial-giant-cell-tumor-patients-in-new-long-term-analysis-presented-at-2019-asco-annual-meeting-300860162.html [SID1234536787]). The data will be presented during a Poster Session on Saturday, June 1, at the 2019 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting in Chicago (Abstract #11042; 8:00-11:00 a.m. CDT).

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The long-term pooled results showed the best overall response with pexidartinib at a median treatment duration of 17 months was 54 percent by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 and 64 percent by Tumor Volume Score (TVS). The median duration of response was not reached.

The safety profile of pexidartinib in the long-term follow-up was consistent with what has been seen in previous analyses. Across the studies, the most frequent adverse events were hair color change (75%), fatigue (60%), nausea (45%), arthralgia (38%), aspartate aminotransferase (AST) increase (30%) and diarrhea (30%). Pexidartinib was associated with two clinically distinct types of hepatic adverse reactions. The first was frequent dose-dependent aminotransferase elevations that may be a pharmacologic effect of CSF1R inhibition. The second hepatic adverse reaction was an idiosyncratic serious mixed or cholestatic hepatotoxicity. Across the pexidartinib clinical program, there were two irreversible cases of cholestatic liver injury, both in non-TGCT study populations. One patient died with advanced cancer and ongoing liver toxicity and one patient required a liver transplant.1

"Looking across the longer-term findings from both the pivotal phase 3 trial and phase 1 extension study, the results demonstrated continued and improved effect of pexidartinib in reducing tumor size in TGCT patients," said A.J. Gelderblom, MD, Chair of the Department of Medical Oncology at the Leiden University Medical Center and an ENLIVEN investigator. "This is important because TGCT is often a chronic disease, and we do not have effective treatment options for patients whose TGCT is inoperable or for which surgery would likely be associated with severe morbidity or functional limitations, like those enrolled in the studies."

Additional data published online ahead of ASCO (Free ASCO Whitepaper) (Abstract #e22527) further highlight the need for new treatment options, showing that TGCT patients missed more time from work due to disability and medical visits. The disability burden seen was greater in patients receiving surgery.

"We are pleased to share additional data that reinforce the potential of pexidartinib to offer clinically meaningful improvement for select patients with TGCT associated with severe morbidity or functional limitations and not amenable to improvement with surgery," said Dale Shuster, Ph.D., Executive Director, Global Oncology R&D, Daiichi Sankyo. "We look forward to working with regulatory authorities and delivering on our goal to help address the significant unmet need that exists in the treatment of this rare and debilitating tumor."

About the Phase 1 Extension Study
Patients enrolled in this phase 1 single-arm, multi-center, extension cohort study included those with a histologically confirmed diagnosis of TGCT with demonstrated tumor progression within the past year that was recurrent, inoperable or resectable but requiring extensive surgery. Following baseline assessment, the efficacy of pexidartinib was assessed radiologically every two months utilizing RECIST 1.1 criteria and TVS. Patients remained on treatment until disease progression or drug intolerance.

Interim data from the phase 1 study were published in The New England Journal of Medicine.2

About the ENLIVEN Study
ENLIVEN, a double-blind, randomized, global multi-center, pivotal phase 3 study, evaluated pexidartinib in patients with symptomatic advanced TGCT for whom surgical removal of the tumor would be associated with potentially worsening functional limitation or severe morbidity. The first part of the study, the double-blind phase, enrolled 120 patients who were randomized (1:1) to receive either pexidartinib or placebo at 1000 mg/day for 2 weeks followed by 800 mg/day for 22 weeks in order to evaluate the efficacy and safety of pexidartinib versus placebo. The primary endpoint of the study was the percentage of patients achieving a complete or partial response after 24 weeks of treatment (Week 25), as assessed with centrally-read MRI scans using RECIST 1.1 criteria. Key secondary endpoints included range of motion, response by tumor volume score, PROMIS physical function, stiffness, and measures of pain reduction.

After completing the first part of the study, patients randomized to either pexidartinib or placebo were eligible to take part in the second part of ENLIVEN, a long-term, open-label part where patients could continue to receive or start to receive pexidartinib. In October 2016, following two reported cases of serious, non-fatal liver toxicity in the ENLIVEN study, the data monitoring committee (DMC) recommended that patients receiving placebo in the first part of the study should no longer be eligible to start pexidartinib in the second part of the study. A total of 120 patients who were enrolled prior to the DMC recommendation continued with the study according to the revised protocol.

About TGCT (PVNS/GCT-TS)
TGCT, also referred to as pigmented villonodular synovitis (PVNS) or giant cell tumor of the tendon sheath (GCT-TS), is a rare, nonmalignant tumor that can be locally aggressive. TGCT affects the synovium-lined joints, bursae and tendon sheaths, resulting in swelling, pain, stiffness and reduced mobility in the affected joint or limb.3, 4, 5

While the exact incidence of TGCT is not known, it is estimated that the incidence of TGCT is 11 to 50 cases per million person-years, based on studies from three countries.6, 7, 8 TGCT is subcategorized into two types: localized, which is more common and accounts for 90 percent of cases, and diffuse, which accounts for 10 percent of cases.7,8 The current standard of care for TGCT is surgical resection.3,4 However, in patients with a recurrent, difficult-to-treat or diffuse form where the tumor can wrap around bone, tendons, ligaments and other parts of the joint, it is more difficult to remove or might not be amenable to improvement with surgery due to the risk of morbidity and potential recurrence. Additional surgeries for more severe cases can lead to significant joint damage, debilitating functional impairments and reduced quality of life, and amputation may be considered.9, 10, 11

Recurrence rates for localized TGCT are estimated to be up to 15 percent following complete resection.4,12,13,14 Diffuse TGCT recurrence rates are estimated to be about 20 to 50 percent following complete resection.5,12,15 TGCT affects all age groups; the diffuse type, on average, occurs most often in people below the age of 40, and the localized type typically occurs in people between 30 and 50 years old. 3,6,7,8

About Pexidartinib
Pexidartinib is an investigational, novel, oral small molecule that potently inhibits the colony stimulating factor-1 receptor (CSF1R), which is a primary growth driver of abnormal cells in the synovium that cause TGCT. Pexidartinib also inhibits c-kit and FLT3-ITD. Pexidartinib was discovered by Plexxikon Inc., the small molecule structure-guided R&D center of Daiichi Sankyo.

Pexidartinib is currently under regulatory review with the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for the treatment of for adult patients with symptomatic TGCT associated with severe morbidity or functional limitations and not amenable to improvement with surgery. In addition to Priority Review designation, pexidartinib has been granted Breakthrough Therapy designation for the treatment of patients with pigmented villonodular synovitis (PVNS) or giant cell tumor of the tendon sheath (GCT-TS), where surgical resection may result in potentially worsening functional limitation or severe morbidity, and Orphan Drug designation for PVNS/GCT-TS by the FDA. Pexidartinib also has received Orphan Drug designation from the European Commission for the treatment of TGCT.

Pexidartinib is an investigational compound that has not been approved for any indication in any country. Safety and efficacy have not been established.

About Daiichi Sankyo Cancer Enterprise
The mission of Daiichi Sankyo Cancer Enterprise is to leverage our world-class, innovative science and push beyond traditional thinking to create meaningful treatments for patients with cancer. We are dedicated to transforming science into value for patients, and this sense of obligation informs everything we do. Anchored by three pillars including our investigational Antibody Drug Conjugate Franchise, Acute Myeloid Leukemia Franchise and Breakthrough Science, we aim to deliver seven distinct new molecular entities over eight years during 2018 to 2025. Our powerful research engines include two laboratories for biologic/immuno-oncology and small molecules in Japan, and Plexxikon Inc., our small molecule structure-guided R&D center in Berkeley, CA. Compounds in pivotal stage development include: [fam-] trastuzumab deruxtecan, an antibody drug conjugate (ADC) for HER2 expressing breast, gastric and other cancers; quizartinib, an oral selective FLT3 inhibitor, for newly-diagnosed and relapsed/refractory FLT3-ITD acute myeloid leukemia (AML); and pexidartinib, an oral CSF1R inhibitor, for TGCT. For more information, please visit: www.DSCancerEnterprise.com.

On June 1, 2019 Nektar Therapeutics (Nasdaq: NKTR) reported that biomarker and clinical data from PIVOT-02 is being presented at the 2019 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Meeting in Chicago, Illinois (Press release, Nektar Therapeutics, JUN 1, 2019, View Source [SID1234536786]).

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New baseline biomarker analyses and updated clinical study efficacy and safety results were shared in a presentation titled, "Baseline tumor-immune signatures associated with response to bempegaldesleukin (NKTR-214) and nivolumab" (Abstract #2623/Poster Board #267) by Michael Hurwitz, Ph.D., M.D. who serves as Assistant Professor of Medicine, Medical Oncology at Yale Cancer Center during the "Developmental Immunotherapy and Tumor Immunobiology" poster session on Saturday, June 1, 2019.

"The Stage IV melanoma patients enrolled in the ongoing PIVOT-02 study continue to experience both deepening and durability of response over time," said Jonathan Zalevsky, Ph.D., Chief Scientific Officer at Nektar Therapeutics. "This translated into a 34% rate of complete response at a 12-month follow-up for the 38 efficacy-evaluable patients in this cohort. Further, 42% of patients achieved a 100% reduction in target lesions. Finally, corresponding lymphocyte data highlight the benefit of replenishing and stimulating T cells continuously over the course of treatment with an I-O doublet regimen."

Bempegaldesleukin (NKTR-214, bempeg) is an investigational, CD122-preferential IL-2 pathway agonist designed to provide sustained signaling through the IL-2 beta-gamma receptor. PIVOT-02 is an ongoing Phase 2 study evaluating bempeg in combination with nivolumab in solid tumors.

Highlights from the biomarker, clinical efficacy and safety data presented at ASCO (Free ASCO Whitepaper) 2019 are provided below:

Biomarkers and Mechanism of Action:

Exploratory biomarker analyses of PIVOT-02 baseline tumor biopsies identified immune signatures that potentially enrich for response in patients with 1L metastatic melanoma and not 1L metastatic urothelial carcinoma.
Notable response rates were seen in both 1L metastatic melanoma and 1L metastatic urothelial cancer patients (ASCO 2019 and ASCO (Free ASCO Whitepaper)-GU 2019), regardless of PD-L1 status or unfavorable tumor microenvironments.
12 Month Follow-Up for 1L Melanoma Cohort in PIVOT-02:
(Response measured by RECIST 1.1 by independent central radiology review for 38 efficacy-evaluable patients per protocol which were treated at the recommended Phase 2 dose in PIVOT-02 and with >1 on treatment scan. Data cut as of March 29, 2019):

At a median time of follow-up of 12.7 months, confirmed objective response rate (ORR) was 53% (20/38) in efficacy-evaluable patients, with 34% (13/38) of patients achieving confirmed complete responses. 42% (16/38) of patients achieved a maximum reduction of 100% in target lesions. DCR, also known as disease control rate (CR+ PR + SD) was 74%.
Median time to response was 2 months. Median duration of response was not reached. At the 12.7 month median follow-up, data were too immature to calculate median progression-free survival (PFS).
80% (16/20) of patients with responses have ongoing responses. Amongst the 35 patients with known pre-treatment PD-L1 status, ORR in PD-L1 negative patients was 6/14 (43%) and in PD-L1 positive patients was 13/21 (62%). One of three patients with unknown PD-L1 baseline status experienced a CR.
The most common (>30%) treatment-related adverse events (TRAEs) were grade 1-2 fatigue (65.9%), pyrexia (61.0%), rash (56.1%), pruritus (48.8%), nausea (41.5%), influenza like illness (39.0%), arthralgia (36.6%), chills (34.1%) and myalgia (31.7%). A total of 6/41 (14.6%) of patients experienced a Grade 3 (G3) or higher TRAE with 4/41 (9.8%) patients discontinuing treatment due to a TRAE. A total of 41 patients have been treated at the RP2D with 3 patients discontinuing prior to 1st scan due to an unrelated treatment-emergent adverse event (n=1) and patient decision (n=2).
A Phase 3 trial evaluating bempeg in combination with nivolumab versus nivolumab in first-line advanced melanoma patients is currently recruiting patients (NCT03635983). A Phase 2 pivotal trial evaluating bempeg in combination with nivolumab in first-line metastatic urothelial cancer is currently recruiting patients (NCT03785925).

Details of the poster presentation are provided below and a link to a copy of the poster presentation is available on Nektar’s corporate website: View Source

Abstract #2623/Poster Board #267
Title: "Baseline tumor-immune signatures associated with response to bempegaldesleukin (NKTR-214) and nivolumab", Hurwitz, M., et al.
Date: Saturday, June 1, 2019, 8:00 a.m. – 11:00 a.m. Central Time
Location: McCormick Place, Exhibit Hall A

On June 1, 2019 ALX Oncology, a clinical-stage immuno-oncology company developing therapies to block the CD47 myeloid checkpoint mechanism, reported new results from its Phase 1 ALX148 solid tumor program at the 2019 ASCO (Free ASCO Whitepaper) Annual Meeting [Abstract #2514] (Press release, ALX Oncology, JUN 1, 2019, View Source [SID1234536777]). As of April 18, 2019, eighty-two patients with various advanced malignancies were administered ALX148 in combination with standard regimens of either trastuzumab (n=30) or pembrolizumab (n=52). Objective responses were observed in expansion cohorts for both gastric/gastroesophageal junction cancer (G/GEJ) and squamous cell carcinoma of the head and neck (HNSCC). Key results are:

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In response-evaluable patients with HER2 positive G/GEJ (n=18) whose tumors had failed prior HER2-targeted therapy, an overall response rate (ORR) of 22% and a disease control rate (DCR) of 28% were observed.
In patients with HNSCC (n=19) whose tumors had failed prior platinum therapy, an ORR of 16% and a DCR of 26% were observed. In checkpoint naïve subjects (n=10), an ORR of 30% and a DCR of 30% were observed.
ALX148 was well tolerated and the most common treatment-related adverse event in combination with trastuzumab was grade 1/2 fatigue (27%), and with pembrolizumab was grade 1/2 increased AST (15%).
Preliminary data from paired pre- and on-study tumor biopsies from combination cohorts showed a statistically significant increase in intra-tumoral macrophages following ALX148 treatment, consistent with ALX148’s mechanism of action as a myeloid checkpoint inhibitor.
"Emerging anti-tumor activity of ALX148 combined with anti-cancer antibodies supports our hypothesis that blocking CD47 with an Fc-inactive molecule can enhance the anti-cancer immune response in patients with varying solid tumor malignancies," said Sophia Randolph M.D., Ph.D., Chief Medical Officer of ALX Oncology. "With its clinical activity and consistent safety profile, ALX148 may become a new cornerstone of immune therapy. We are excited to continue evaluating its clinical benefit in populations in need of novel treatments."

About ALX148
ALX148, designed for combination therapy, is a fusion protein comprised of an engineered high affinity CD47 binding domain of SIRPα linked to an inactive Fc region of human immunoglobulin. ALX148 potently and specifically binds CD47 and blocks its interaction with SIRPα, thus inhibiting a key immune checkpoint mechanism exploited by cancer cells. In preclinical studies, ALX148 bridges innate and adaptive immunity to maximize anti-tumor response in combinations with targeted anti-cancer antibodies and checkpoint inhibitors via Fc-dependent and Fc-independent mechanisms. No adverse effects on CD47-expressing normal blood cells were seen in ALX148 preclinical studies.

The ALX148 Phase 1 clinical trial is a two-part study that evaluates the safety, pharmacokinetics, and pharmacodynamics of ALX148. Enrollment to the combination therapy portion in which ALX148 is administered with approved anti-cancer antibodies is ongoing. For more information about the Phase 1 study, please visit clinicaltrials.gov, identifier number NCT03013218.

On June 1, 2019 Kite, a Gilead Company (Nasdaq: GILD), reported results from the completed Phase 1 of the ZUMA-3 study evaluating KTE-X19, an investigational CD19 chimeric antigen receptor T (CAR T) cell therapy (Press release, Kite Pharma, JUN 1, 2019, View Source [SID1234536773]). ZUMA-3 is a single-arm Phase 1/2 study in adult patients with relapsed or refractory acute lymphoblastic leukemia (ALL). The results provide guidance on dosing and safety management for KTE-X19 to inform the ongoing Phase 2 study. The data were presented during an oral session at the 2019 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting in Chicago, May 31 – June 4 (Abstract #7006).

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This press release features multimedia. View the full release here: View Source

By the end of Phase 1, 45 patients received KTE-X19 at one of three different doses levels [2 x 106 cells/kg (n=6), 1 x 106 cells/kg (n=23), or 0.5 x 106 cells/kg (n=16)]. Patients enrolled in this study were primary refractory or relapsed/refractory after at least two prior lines of therapy. Of 41 patients who were evaluable for efficacy after a minimum two months of follow-up (median follow-up of 16 months), 68 percent achieved complete response (CR) or CR with incomplete hematological recovery (CRi) and 100 percent of responders had undetectable minimal residual disease (MRD). Of the 23 patients treated with the dose level that will be used in the ongoing Phase 2 study (1 x 106 cells/kg), 19 were evaluable for efficacy. At the time of data cut-off (median duration of remission = 12.9 months), 16 (84 percent) patients achieved CR or CRi, and 12 patients (75 percent) were in ongoing response.

No dose-limiting toxicities (DLTs) were identified. Grade ≥3 cytokine release syndrome (CRS) events and neurologic events occurred in 29 percent and 38 percent of all patients, respectively. As previously reported, two patients experienced KTE-X19–related Grade 5 adverse events (AEs) during the study; one developed stroke in the context of CRS and neurologic events, and one experienced multiorgan failure secondary to CRS. Among patients receiving 1 x 106 cell/kg (n=23), 26 percent experienced Grade ≥3 CRS, and 43 percent experienced Grade ≥3 neurologic events.

A revised AE management protocol was implemented in nine patients treated with 1 x106 cells/kg of KTE-X19 during the study. In this revised protocol, corticosteroids were initiated at onset of Grade ≥2 neurologic events (versus previous onset of Grade 3) and tocilizumab was only given for management of toxicities in the context of CRS (versus prophylactic administration in Cohort 2). Of those patients, two (22 percent) had Grade 3 CRS and one (11 percent) had Grade 3 neurologic events. There were no Grade 4/5 events.

"Adults with relapsed or refractory ALL represent an extremely difficult-to-treat patient population," said Bijal Shah, MD, ZUMA-3 investigator and medical oncologist, Moffitt Cancer Center, Tampa, Florida. "We’re encouraged by the high response rates in this study, as well as the reduced incidence and severity of CRS and neurologic events that were observed following implementation of the revised safety management protocol. We are now evaluating the use of KTE-X19 at the selected dose with this safety management protocol in the ongoing ZUMA-3 Phase 2 study."

"The completion of the Phase 1 portion of the ZUMA-3 trial is an important milestone for our second investigational CAR T cell therapy," said John McHutchison, AO, MD, Chief Scientific Officer, Head of Research and Development, Gilead. "We are pleased with the high response rates observed with KTE-X19 in this trial, and the progress of our broader effort aimed to further improve the benefit/risk profile of CAR T therapy through the investigation of novel safety management approaches."

This abstract has also been selected to be included in the 2019 Best of ASCO (Free ASCO Whitepaper) program, which will be held this summer following the ASCO (Free ASCO Whitepaper) Annual Meeting.

KTE-X19 is an investigational therapy that has not been approved by the U.S. Food and Drug Administration (FDA) or any regulatory authority for any uses. Efficacy and safety have not been established.

About ALL

ALL is an aggressive type of blood cancer which can also involve the lymph nodes, spleen, liver, central nervous system and other organs.

About ZUMA-3

ZUMA-3 is an ongoing multicenter, registrational Phase 1/2 study in adult patients (≥18 years old) with ALL whose disease is refractory to or has relapsed following standard chemotherapy or hematopoietic stem cell transplantation. The objectives of the study are to evaluate the safety and efficacy of KTE-X19 in this patient population.

About KTE-X19

KTE-X19 is an investigational CD19 CAR T cell therapy. KTE-X19 has the same construct as axicabtagene ciloleucel; however, the manufacturing process for KTE-X19 differs from that of axicabtagene ciloleucel and includes the enrichment of lymphocytes. Lymphocyte enrichment is necessary in certain B-cell malignancies for which KTE-X19 in under investigation. KTE-X19 is currently in Phase 1/2 trials in acute lymphoblastic leukemia (ALL), mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL).