DELTA-1: A global, multicenter, phase 2 study of ITIL-168, an unrestricted autologous tumor-infiltrating lymphocyte (TIL) cell therapy, in adult patients with advanced cutaneous melanoma

TPS9594

Background: Patients (pts) with advanced (unresectable or metastatic) cutaneous melanoma and persistent disease after checkpoint inhibitor therapy have poor outcomes and limited treatment options, highlighting a significant unmet medical need (Schadendorf D et al. Lancet. 2018;392:971-984). Investigational autologous TIL cell therapies have shown promise in this population, partly attributable to their intrinsic and patient-specific antitumor activity (Borch TH et al. J Immunother Cancer. 2020;8:e000668). Made from each patient’s digested and cryopreserved tumor, ITIL-168 is an autologous TIL cell therapy manufactured to offer an unrestricted T-cell receptor repertoire. A single-center, compassionate use clinical series demonstrated the feasibility and clinical utility of an earlier version of ITIL-168, with a high overall response rate among pts previously treated with PD-1 inhibitor (PD-1i) therapy (58%, n = 12; Pillai M et al. Ann Oncol. 2021;32[suppl 5]:S882). DELTA-1 (NCT05050006) is a global, multicenter phase 2 study to evaluate efficacy and safety of ITIL-168 in pts with cutaneous melanoma relapsed or refractory to a PD-1i, pts intolerant to a PD-1i, and pts whose current best response to a PD-1i is stable disease. Methods: Pts aged ≥18 years with histologically confirmed advanced cutaneous melanoma, ECOG performance status 0-1, and adequate organ function will be enrolled in 1 of 3 cohorts. Cohort 1 (n≈80) will include pts who relapsed after or were refractory to ≥1 prior line of systemic therapy, including a PD-1i and, if BRAF-mutated, a BRAFi ± MEKi. Cohorts 2 and 3 (n≈25 each) will include pts intolerant to PD-1i and those with stable disease after ≥4 doses of PD-1i, respectively. After tumor resection for TIL harvest, pts must have ≥1 remaining measurable lesion per RECIST 1.1. Pts with uveal, acral, or mucosal melanoma, prior allogeneic transplant or cell therapy, and with central nervous system (CNS) disorder or symptomatic and/or untreated CNS metastases are ineligible. Pts will receive 5 days of lymphodepleting chemotherapy (cyclophosphamide ×2 days overlapping with fludarabine ×5 days) followed by a single ITIL-168 infusion (≥5×109 cells) and supportive short-course, high-dose IL-2. The primary endpoint is objective response rate (ORR) per central review. Secondary endpoints include duration of response, progression-free survival, overall survival, disease control rate, TIL persistence, and safety. Hypothesis testing of ORR will be performed for cohort 1. The primary analysis will occur when all pts in the cohort 1 modified intent-to-treat population have been followed for ≥6 months after the first posttreatment disease assessment. DELTA-1 opened for enrollment in September 2021. Updated site information will be given at the time of presentation. Clinical trial information: NCT05050006.

544 DELTA-1: A global, multicenter phase 2 study of ITIL-168, an unrestricted autologous tumor-infiltrating lymphocyte (TIL) cell therapy, in adult patients with advanced cutaneous melanoma

Background

Patients with advanced cutaneous melanoma and persistent disease after checkpoint inhibitor therapy have poor outcomes and limited treatment options, highlighting a significant unmet medical need.1 Autologous TIL cell therapies have shown promise in this population attributable, in part, to their intrinsic and patient-specific antitumor activity2; however, no such therapies are approved. Made from each patient‘s digested and cryopreserved tumor, ITIL-168 is an autologous TIL cell therapy manufactured to offer an unrestricted T-cell receptor repertoire. A single-center compassionate use clinical series demonstrated the feasibility and clinical utility of an earlier version of ITIL-168.3 DELTA-1 is a global, multicenter phase 2 study to evaluate efficacy and safety of ITIL-168. DELTA-1 will enroll patients with melanoma relapsed after or refractory to PD-1 inhibitors (PD-1i), patients intolerant to PD-1i, and patients whose best response to PD-1i was stable disease.

Methods

Patients aged ≥18 years with histologically confirmed advanced cutaneous melanoma, ECOG performance status 0–1, and adequate organ function will be enrolled in 1 of 3 cohorts. Cohort 1 (n≈80) will include patients who relapsed after or were refractory to ≥1 prior line of systemic therapy, including a PD-1i and, if BRAF-mutated, a BRAFi ± MEKi. Cohorts 2 and 3 (n≈25 each) will include patients intolerant to PD-1i and those with stable disease after ≥4 doses of PD-1i, respectively. After tumor resection for TIL harvest, patients must have ≥1 remaining measurable lesion per Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. Patients with uveal, acral, or mucosal melanoma, prior allogeneic transplant or cell therapy, and with central nervous system (CNS) disorder or symptomatic and/or untreated CNS metastases are ineligible. Patients will receive 5 days of lymphodepleting chemotherapy (cyclophosphamide ×2 days overlapping with fludarabine ×5 days) followed by a single ITIL-168 infusion (≥5×109 cells) and supportive short course high-dose IL-2. The primary endpoint is objective response rate (ORR) per central review. Key secondary endpoints include duration of response, progression-free survival, overall survival, disease control rate, TIL persistence, and safety. Hypothesis testing of ORR will be performed for cohort 1. Two interim analyses will occur after 20 patients in cohort 1 have been followed for ≥28 days (safety) and evaluated for response ≥3 months after ITIL-168 infusion (futility). The primary analysis will occur when all patients in the cohort 1 modified intent-to-treat population have been followed for ≥6 months after the first posttreatment disease assessment.

Acknowledgements

Medical writing support was provided by Christopher Waldapfel, PharmD, of Instil Bio, Inc, and Phylicia Aaron, PhD, of Nexus GG Science, with funding from Instil Bio, Inc.

References

Schadendorf D, van Akkoi ACJ, Berking C, et al. Melanoma. Lancet 2018;392(10151):971–984.

Borch TH, Anderson R, Ellebaek E, et al. Future role for adoptive T-cell therapy in checkpoint inhibitor-resistant metastatic melanoma. J Immunother Cancer 2020;8(2):e000668.

Hawkins RE, Jiang Y, Lorigan PC, et al. Clinical feasibility and treatment outcomes with unselected autologous tumor infiltrating lymphocyte therapy in patients with advanced cutaneous melanoma. Cancer Res 2021;81(13):LB150.

Ethics Approval

All patients will provide written informed consent. The study will be approved by the Institutional Review Board/Independent Ethics Committee at each site and conducted in accordance with the Good Clinical Practice Guidelines of the International Conference on Harmonisation.

Consent

N/A; the abstract does not contain sensitive or identifiable patient information.

Axicabtagene Ciloleucel CAR T-Cell Therapy in Refractory Large B-Cell Lymphoma

BACKGROUND

In a phase 1 trial, axicabtagene ciloleucel (axi-cel), an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, showed efficacy in patients with refractory large B-cell lymphoma after the failure of conventional therapy.

METHODS

In this multicenter, phase 2 trial, we enrolled 111 patients with diffuse large B-cell lymphoma, primary mediastinal B-cell lymphoma, or transformed follicular lymphoma who had refractory disease despite undergoing recommended prior therapy. Patients received a target dose of 2×106 anti-CD19 CAR T cells per kilogram of body weight after receiving a conditioning regimen of low-dose cyclophosphamide and fludarabine. The primary end point was the rate of objective response (calculated as the combined rates of complete response and partial response). Secondary end points included overall survival, safety, and biomarker assessments.

RESULTS

Among the 111 patients who were enrolled, axi-cel was successfully manufactured for 110 (99%) and administered to 101 (91%). The objective response rate was 82%, and the complete response rate was 54%.With a median follow-up of 15.4 months, 42% of the patients continued to have a response, with 40% continuing to have a complete response. The overall rate of survival at 18 months was 52%. The most common adverse events of grade 3 or higher during treatment were neutropenia (in 78% of the patients), anemia (in 43%), and thrombocytopenia (in 38%). Grade 3 or higher cytokine release syndrome and neurologic events occurred in 13% and 28% of the patients, respectively. Three of the patients died during treatment. Higher CAR T-cell levels in blood were associated with response.

CONCLUSIONS

In this multicenter study, patients with refractory large B-cell lymphoma who received CAR T-cell therapy with axi-cel had high levels of durable response, with a safety profile that included myelosuppression, the cytokine release syndrome, and neurologic events. (Funded by Kite Pharma and the Leukemia and Lymphoma Society Therapy Acceleration Program; ZUMA-1 ClinicalTrials.gov number, NCT02348216 .).

Clinical and biologic covariates of outcomes in ZUMA-1: A pivotal trial of axicabtagene ciloleucel (axi-cel; KTE-C19) in patients with refractory aggressive non-Hodgkin lymphoma (r-NHL)

7512

Background: Outcomes in activated B cell subtype diffuse large B cell lymphoma (ABC-DLBCL) and r-NHL are poor (Sehn Blood 2015, Crump ASCO 2016). ZUMA-1 is the first, multicenter trial of anti-CD19 chimeric antigen receptor (CAR) T cells, axi-cel, in r-NHL. Methods: Dosing and eligibility were per Neelapu ASH 2016. The primary endpoint was objective response rate (ORR); secondary endpoints were duration of response (DOR), overall survival (OS), and safety. Cell of origin (COO) and CD19 status were assessed centrally using Lymphoma Subtyping Test NanoString (Wallden JCO 2015) and a validated immunohistochemistry assay, respectively. Results: As of Jan 27, 2017, 111 patients (pts) were enrolled; the manufacturing success rate was 99% with an average 17-d turnaround time; 101 pts (modified intent-to-treat [mITT] population) received axi-cel. In the mITT population, the ORR was 82% (complete response [CR], 54%). With 8.7 m median follow-up, 44% remain in response and 39% in CR. The median DOR was 8.1 m and not reached (NR) for pts with CR. Median OS was NR. Results for clinical and biologic covariates are listed in the table. In pts who received tocilizumab (n = 43) and/or steroids (n = 27) for cytokine release syndrome (CRS) and/or neurologic events (NE), ORR was 84% and 78%, respectively. Most common grade ≥3 adverse events (AEs) were neutropenia (66%), leukopenia (44%), anemia (43%), febrile neutropenia (31%), thrombocytopenia (24%), and encephalopathy (21%). Rates of grade ≥3 CRS and NE were 13% and 28%, respectively. There were 3 grade 5 AEs (Neelapu ASH 2016). Conclusions: Axi-cel induced an ORR of 82% in pts with r-NHL, response is ongoing in 44% of pts at 8.7 m. Similar clinical responses were observed in pts with r-ABC-DLBCL. AEs were manageable and the use of tocilizumab/steroids did not appear to impact ORR. Drs Locke and Neelapu contributed equally. Funding source: Kite Pharma and Leukemia & Lymphoma Society Therapy Acceleration Program Clinical trial information: NCT02348216. [Table: see text]

Zuma-6: Phase 1-2 multicenter study evaluating safety and efficacy of axicabtagene ciloleucel (axi-cel; KTE-C19) in combination with atezolizumab in patients with refractory diffuse large b-cell lymphoma (DLBCL)

TPS7572

Background: Approximately 1/3 of patients with DLBCL, the most common type of B-cell lymphoma, will become refractory to standard combination chemotherapy and have uniformly poor clinical outcomes (Crump, ASCO 2016). Axi-cel (autologous anti-CD19 chimeric antigen receptor [CAR] T cell therapy) has shown promising response rates in patients with refractory DLBCL compared with standard approaches, although some patients do not respond or progress after an initial response (Locke, Mol Ther 2016). Expression of PD-L1 on DLBCL cells and activation-dependent expression of PD-1 on CAR T cells after infusion led to the hypothesis that PD-1 pathway blockade may augment the activity of axi-cel and result in improved clinical outcomes. This study will evaluate safety and efficacy of axi-cel when given with atezolizumab (anti–PD-L1 antibody), delivered sequentially, in patients with refractory DLBCL. Methods: Phase 1 will enroll ~3-9 patients to estimate the incidence of dose-limiting toxicities. Phase 2 will enroll ~22 patients to evaluate safety and efficacy, with a primary endpoint of complete response (CR) rate (Cheson 2007). Secondary endpoints include key efficacy outcomes such as objective response rate (CR+partial response [PR]), duration of response, progression-free and overall survival, and safety and biomarker outcomes. Eligible adult patients will have received prior adequate therapy (including anti-CD20 monoclonal antibody and an anthracycline-based regimen) and have an ECOG PS of 0-1 and adequate bone marrow and organ function. Patients with a history of Richter transformation, transformed follicular lymphoma, CNS disease, or active infection are not eligible. Patients will receive fludarabine 30 mg/m2/d and cyclophosphamide 500 mg/m2/d × 3 d, followed by a single infusion of axi-cel (target dose, 2 × 106anti-CD19 CAR T cells/kg) followed by atezolizumab 1200 mg given every 21 d for 4 doses (phase 1, first dose to occur 21, 14, and 1 d after axi-cel infusion in cohorts 1, 2, and 3, respectively). The study opened to accrual in September 2016. Clinical trial information: NCT02926833.

Updated results from ZUMA-3, a phase 1/2 study of KTE-C19 chimeric antigen receptor (CAR) T cell therapy, in adults with high-burden relapsed/refractory acute lymphoblastic leukemia (R/R ALL)

3024

Background: Promising results have been observed with KTE-C19, an anti-CD19 CAR T cell therapy, in refractory aggressive NHL in the ZUMA-1 trial (Blood 2016;128:LBA-6). We present here updated results from the ZUMA-3 phase 1 trial of KTE-C19 in adult patients (pts) with R/R ALL. Methods: Adult (≥18 y) pts with R/R ALL (Ph+ eligible), ≥25% bone marrow (BM) blasts, adequate organ function and ECOG status 0-1 received 1 or 2×106 CAR T cells/kg after conditioning with cyclophosphamide + fludarabine. Phase 1 primary endpoint is incidence of dose-limiting toxicity (DLT). Secondary endpoints include efficacy outcomes and biomarker associations. Results: As of Nov 1, 2016, 11 pts were enrolled; 10 received KTE-C19. One pt had a serious adverse event (SAE) prior to dosing and was not treated. KTE-C19 was successfully manufactured in all pts across a broad range of baseline absolute lymphocyte counts in 6 days in a centralized facility, with an approximate 2-week turnaround time. Pts were 60% men with 1-4 prior lines of therapy and high disease burden (median, 70% BM blasts). No pt (0/3) experienced a DLT at the 2×106 dose. Phase 1 was expanded to 6 pts at the same dose; 1 grade (Gr) 5 AE (multiorgan failure due to cytokine release syndrome [CRS]) was observed. Subsequent pts (4) received 1×106 CAR T cells/kg. Overall, the most common Gr≥3 AEs were cytopenias (80%), febrile neutropenia (50%), pyrexia (40%), and transaminitis (40%). Gr≥3 CRS and neurologic events (NEs) were reported in 20% and 40% of pts, respectively. Cerebral edema was not observed. All CRS (except Gr5) and 5 of 6 NEs (1 Gr3 ongoing at cut-off) resolved. Of the 8 efficacy evaluable pts, 6 achieved an MRD-negative (MRD–) complete response (CR, or CR + partial or incomplete hematopoietic recovery). Updated results will include additional pt follow-up and biomarker data. Conclusions: No DLTs were observed with KTE-C19 in adult pts with high BM disease burden; one pt had G5 CRS after the DLT cohort. Manufacturing was successful in all pts; most pts achieved an MRD– CR. Based on these results, ZUMA-3 continues to enroll pts with additional measures implemented to further enhance safety. Clinical trial information: NCT02614066.

Phase 1 Results of ZUMA-1: A Multicenter Study of KTE-C19 Anti-CD19 CAR T Cell Therapy in Refractory Aggressive Lymphoma

Outcomes for patients with refractory diffuse large B cell lymphoma (DLBCL) are poor. In the multicenter ZUMA-1 phase 1 study, we evaluated KTE-C19, an autologous CD3ζ/CD28-based chimeric antigen receptor (CAR) T cell therapy, in patients with refractory DLBCL. Patients received low-dose conditioning chemotherapy with concurrent cyclophosphamide (500 mg/m2) and fludarabine (30 mg/m2) for 3 days followed by KTE-C19 at a target dose of 2 × 106 CAR T cells/kg. The incidence of dose-limiting toxicity (DLT) was the primary endpoint. Seven patients were treated with KTE-C19 and one patient experienced a DLT of grade 4 cytokine release syndrome (CRS) and neurotoxicity. Grade ≥3 CRS and neurotoxicity were observed in 14% (n = 1/7) and 57% (n = 4/7) of patients, respectively. All other KTE-C19-related grade ≥3 events resolved within 1 month. The overall response rate was 71% (n = 5/7) and complete response (CR) rate was 57% (n = 4/7). Three patients have ongoing CR (all at 12+ months). CAR T cells demonstrated peak expansion within 2 weeks and continued to be detectable at 12+ months in patients with ongoing CR. This regimen of KTE-C19 was safe for further study in phase 2 and induced durable remissions in patients with refractory DLBCL.

Deep Impact: observations from a worldwide Earth-based campaign

On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics.

Identification of candidate target genes for EVI-1, a zinc finger oncoprotein, using a novel selection strategy

We have sought to identify and isolate target genes for the zinc finger protein, EVI-1, which has been implicated in the genesis of myelogenous leukemia both in mouse and human. We have approached this with a two-step selection: we first selected for genomic fragments of mouse DNA that bind to the protein with high affinity; second, we employed cDNA hybrid selection to identify gene sequences contained within these fragments. We show that we have constructed a sublibrary of genomic fragments that contains a significant fraction of the EVI-1-binding sites in the mouse genome. Our data has allowed us to estimate that there are approximately 4300 binding sites per haploid genome in the mouse. We further demonstrate that by using cDNA hybrid selection, it is relatively straightforward to isolate cDNAs that correspond to genes embedded in the EVI-1-binding sublibrary. Several of these are novel, but are represented in databases of anonymous human or mouse cDNAs (expressed sequence tags). One selected gene is Itpr2, encoding the inositol trisphosphate type two receptor, which is transcriptionally regulated during myelopoiesis. Finally, using a chimeric EVI-1-VP16-fusion protein under the control of a tetracycline-regulated system, we have shown that this chimeric activator can directly regulate Itpr2.