Intrathecal bivalent CAR T cells targeting EGFR and IL13Rα2 in recurrent glioblastoma: phase 1 trial interim results.

Recurrent glioblastoma (rGBM) remains a major unmet medical need, with a median overall survival of less than 1 year. Here we report the first six patients with rGBM treated in a phase 1 trial of intrathecally delivered bivalent chimeric antigen receptor (CAR) T cells targeting epidermal growth factor receptor (EGFR) and interleukin-13 receptor alpha 2 (IL13Rα2). The study's primary endpoints were safety and determination of the maximum tolerated dose. Secondary endpoints reported in this interim analysis include the frequency of manufacturing failures and objective radiographic response (ORR) according to modified Response Assessment in Neuro-Oncology criteria. All six patients had progressive, multifocal disease at the time of treatment. In both dose level 1 (1 ×107 cells; n = 3) and dose level 2 (2.5 × 107 cells; n = 3), administration of CART-EGFR-IL13Rα2 cells was associated with early-onset neurotoxicity, most consistent with immune effector cell-associated neurotoxicity syndrome (ICANS), and managed with high-dose dexamethasone and anakinra (anti-IL1R). One patient in dose level 2 experienced a dose-limiting toxicity (grade 3 anorexia, generalized muscle weakness and fatigue). Reductions in enhancement and tumor size at early magnetic resonance imaging timepoints were observed in all six patients; however, none met criteria for ORR. In exploratory endpoint analyses, substantial CAR T cell abundance and cytokine release in the cerebrospinal fluid were detected in all six patients. Taken together, these first-in-human data demonstrate the preliminary safety and bioactivity of CART-EGFR-IL13Rα2 cells in rGBM. An encouraging early efficacy signal was also detected and requires confirmation with additional patients and longer follow-up time. ClinicalTrials.gov identifier: NCT05168423 .

Anti-BCMA/CD19 CAR T Cells with Early Immunomodulatory Maintenance for Multiple Myeloma Responding to Initial or Later-Line Therapy.

We conducted a phase I clinical trial of anti-BCMA chimeric antigen receptor T cells (CART-BCMA) with or without anti-CD19 CAR T cells (huCART19) in multiple myeloma (MM) patients responding to third- or later-line therapy (phase A, N = 10) or high-risk patients responding to first-line therapy (phase B, N = 20), followed by early lenalidomide or pomalidomide maintenance. We observed no high-grade cytokine release syndrome (CRS) and only one instance of low-grade neurologic toxicity. Among 15 subjects with measurable disease, 10 exhibited partial response (PR) or better; among 26 subjects responding to prior therapy, 9 improved their response category and 4 converted to minimal residual disease (MRD)-negative complete response/stringent complete response. Early maintenance therapy was safe, feasible, and coincided in some patients with CAR T-cell reexpansion and late-onset, durable clinical response. Outcomes with CART-BCMA + huCART19 were similar to CART-BCMA alone. Collectively, our results demonstrate favorable safety, pharmacokinetics, and antimyeloma activity of dual-target CAR T-cell therapy in early lines of MM treatment. SIGNIFICANCE: CAR T cells in early lines of MM therapy could be safer and more effective than in the advanced setting, where prior studies have focused. We evaluated the safety, pharmacokinetics, and efficacy of CAR T cells in patients with low disease burden, responding to current therapy, combined with standard maintenance therapy. This article is highlighted in the In This Issue feature, p. 101.

Personalized gene therapy locks out HIV, paving the way to control virus without antiretroviral drugs.

INTRODUCTION: Advances in adoptive immunotherapy have enabled gene therapy approaches to be tested in clinical trials that involve the transfer of engineered immune cells to specifically target HIV-infected cells or block HIV infection or transmission. Genetic editing through engineered targeted nucleases provides a method for producing cells that are permanently resistant to HIV. AREAS COVERED: Here, we discuss current and developing gene therapy approaches aimed to confer resistance to HIV infection at the cellular level by targeting viral or cellular elements, with a focus on gene editing strategies that target viral entry. Human gene therapy trials in HIV infection are reviewed. EXPERT OPINION: In concept, a single infusion of genetically modified cells could potentially reduce the need for lifelong medication by providing long-term control over the virus (functional immunity). While the dream of completely eliminating viral reservoirs (sterilizing immunity) is appealing, this presents a significant additional hurdle and may not be necessary to improve long-term health. A single infusion, or a small number of infusions, of engineered cells may be shown in confirmatory clinical trials to produce a meaningful biologic effect. These techniques have implications for targeted gene therapy in HIV and other diseases.

Therapeutic vaccination against the rhesus lymphocryptovirus EBNA-1 homologue, rhEBNA-1, elicits T cell responses to novel epitopes in rhesus macaques.

Epstein-Barr virus (EBV) is a vaccine/immunotherapy target due to its association with several human malignancies. EBNA-1 is an EBV protein consistently expressed in all EBV-associated cancers. Herein, EBNA-1-specific T cell epitopes were evaluated after AdC-rhEBNA-1 immunizations in chronically lymphocryptovirus-infected rhesus macaques, an EBV infection model. Preexisting rhEBNA-1-specific responses were augmented in 4/12 animals, and new epitopes were recognized in 5/12 animals after vaccinations. This study demonstrated that EBNA-1-specific T cells can be expanded by vaccination.

Day-4 myeloid dendritic cells pulsed with whole tumor lysate are highly immunogenic and elicit potent anti-tumor responses.

"Day-7" myeloid DCs are commonly used in the clinic. However, there is a strong need to develop DCs faster that have the same potent immunostimulatory capacity as "Day-7" myeloid DCs and at the same time minimizing time, labor and cost of DC preparations. Although "2 days" DCs can elicit peptide-specific responses, they have not been demonstrated to engulf, process and present complex whole tumor lysates, which could be more convenient and personalized source of tumor antigens than defined peptides. In this preclinical study, we evaluated the T-cell stimulatory capacity of Day-2, Day-4, and Day-7 cultured monocyte-derived DCs loaded with SKOV3 cell whole lysate prepared by freeze-thaw or by UVB-irradiation followed by freeze-thaw, and matured with lipopolysaccharide (LPS) and interferon (IFN)-gamma. DCs were evaluated for antigen uptake, and following maturation with LPS and IFN-gamma, DCs were assessed for expression of CD80, CD40, CD86, ICAM-1 and CCR7, production of IL-12p70 and IP-10, and induction of tumor-specific T-cell responses. Day-4 and Day-7 DCs exhibited similar phagocytic abilities, which were superior to Day-2 DCs. Mature Day-7 DCs expressed the highest CD40 and ICAM-1, but mature Day-4 DCs produced the most IL-12p70 and IP-10. Importantly, Day-4 and Day-7 DCs derived from ovarian cancer patients stimulated equally strongly tumor-specific T-cell responses. This is the first study demonstrating the highly immunogenic and strong T-cell stimulatory properties of Day-4 myeloid DCs, and provided important preclinical data for rapid development of potent whole tumor lysate-loaded DC vaccines that are applicable to many tumor types.