CD22 CAR T cells demonstrate high response rates and safety in pediatric and adult B-ALL: Phase 1b results.

Chimeric antigen receptor (CAR) T cells targeting CD22 (CD22-CAR) provide a therapeutic option for patients with CD22+ malignancies with progression after CD19-directed therapies. Using on-site, automated, closed-loop manufacturing, we conducted parallel Phase 1b clinical trials investigating a humanized CD22-CAR with 41BB costimulatory domain in children and adults with heavily treated, relapsed/refractory (r/r) B-ALL. Of 19 patients enrolled, 18 had successful CD22-CAR manufacturing, and 16 patients were infused. High grade (3-4) cytokine release syndrome (CRS) and immune effector-cell-associated neurotoxicity syndrome (ICANS) each occurred in only one patient; however, three patients experienced immune-effector-cell-associated hemophagocytic lymphohistiocytosis-like syndrome (IEC-HS). Twelve of 16 patients (75%) achieved CR with an overall 56% MRD-negative CR rate. Duration of response was overall limited (median 77 days), and CD22 expression was downregulated in 4/12 (33%) available samples at relapse. In summary, we demonstrate that closed-loop manufacturing of CD22-CAR T cells is feasible and is associated with a favorable safety profile and high CR rates in pediatric and adult r/r B-ALL, a cohort with limited CD22-CAR reporting.

Custom CARs: Leveraging the Adaptability of Allogeneic CAR Therapies to Address Current Challenges in Relapsed/Refractory DLBCL.

Cellular therapies have transformed the treatment of relapsed/refractory diffuse large B-cell lymphoma (r/r DLBCL), which typically does not respond well to salvage chemotherapy. Recently, approximately 40% of r/r DLBCL patients across three different trials achieved a complete remission at 1 year after receiving treatment with autologous chimeric antigen receptor (CAR) T cells (auto-CARs). These successes have prompted studies of auto-CARs in second-line settings, in which axicabtagene ciloleucel and lisocabtagene maraleucel both showed improved event-free survival over autologous hematopoietic cell transplantation (AHCT). While encouraging, this data also highlights that 60% of patients relapse or progress following treatment with auto-CARs. Individual disease characteristics and logistical challenges of cell engineering also limit patients' eligibility for auto-CARs. Allogeneic CAR T cells (allo-CARs) may address some of these limitations as they may mitigate delays associated with auto-CARs, thereby reducing the need for bridging chemotherapies and increasing availability of cellular products for patients with aggressive lymphomas. By being sourced from healthy donors who have never been exposed to cytotoxic chemotherapy, allo-CARs can be created from T cells with better fitness. Allo-CARs made from specific cellular subsets (e.g., stem cell memory or naïve/early memory T cells) may also have increased efficacy and long-term persistence. Additionally, allo-CARs have been successfully created from other cell types, including natural killer cells, gamma-delta T-cells and induced pluripotent stem cells. These cell types can be engineered to target viral antigens, enabling precision targeting of virally driven DLBCL. As allogeneic donor cells can be banked and cryopreserved in batches, they can be made more readily available, potentially reducing logistical hurdles and costs compared to engineering auto-CARs. This may ultimately create a more sustainable platform for cell therapies. Challenges with allo-CARs that will need to be addressed include graft versus host disease, alloimmunization, potentially decreased persistence relative to auto-CARs, and antigen escape. In short, the adaptability of allo-CARs makes them ideal for treating patients with r/r DLBCL who have progressed through standard chemotherapy, AHCT, or auto-CARs. Here, we review the published literature on patients with r/r DLBCL treated with allogeneic CAR products manufactured from various cell types as well as forthcoming allogeneic CAR technologies.

Comprehensive Clinical and Molecular Characterization of KRAS G12C-Mutant Colorectal Cancer.

PURPOSE: KRAS p.G12C mutations occur in approximately 3% of metastatic colorectal cancers (mCRC). Recently, two allosteric inhibitors of KRAS p.G12C have demonstrated activity in early phase clinical trials. There are no robust studies examining the behavior of this newly targetable population. METHODS: We queried the MD Anderson Cancer Center data set for patients with colorectal cancer who harbored KRAS p.G12C mutations between January 2003 and September 2019. Patients were analyzed for clinical characteristics, overall survival (OS), and progression-free survival (PFS) and compared against KRAS nonG12C. Next, we analyzed several internal and external data sets to assess immune signatures, gene expression profiles, hypermethylation, co-occurring mutations, and proteomics. RESULTS: Among the 4,632 patients with comprehensive molecular profiling, 134 (2.9%) were found to have KRAS p.G12C mutations. An additional 53 patients with single gene sequencing were included in clinical data but excluded from prevalence analysis allowing for 187 total patients. Sixty-five patients had de novo metastatic disease and received a median of two lines of chemotherapy without surgical intervention. For the first three lines of chemotherapy, the median PFS was 6.4 months (n = 65; 95% CI, 5.0 to 7.4 months), 3.9 months (n = 47; 95% CI, 2.9 to 5.9 months), and 3.0 months (n = 21; 95% CI, 2.0 to 3.4 months), respectively. KRAS p.G12C demonstrated higher rates of basal EGFR activation compared with KRAS nonG12C. When compared with an internal cohort of KRAS nonG12C, KRAS p.G12C patients had worse OS. CONCLUSION: PFS is poor for patients with KRAS p.G12C metastatic colorectal cancer. OS was worse in KRAS p.G12C compared with KRAS nonG12C patients. Our data highlight the innate resistance to chemotherapy for KRAS p.G12C patients and serve as a historical comparator for future clinical trials.

Cytokine gene polymorphisms are associated with response to blinatumomab in B-cell acute lymphoblastic leukemia.

Blinatumomab is a bispecific T cell-engaging antibody approved for treatment of relapsed/refractory (r/r) ALL, with 40%-50% complete response (CR)/CR with incomplete count recovery (CRi). Cytokine release syndrome (CRS) as a major adverse effect after blinatumomab therapy. Here, we evaluated the possible association between single-nucleotide polymorphisms (SNPs) in cytokine genes, disease response, and CRS in r/r ALL patients who received blinatumomab between 2012 and 2017 at our center (n = 66), using patients' archived DNA samples. With a median duration of 9.5 months (range: 1-37), 37 patients (56.1%) achieved CR/CRi, 54 (81.8%) experienced CRS (G1: n = 35, G2: n = 14, G3: n = 5), and 9 (13.6%) developed neurotoxicity. By multivariable analysis, after adjusting for high disease burden, one SNP on IL2 (rs2069762), odds ratio (OR) = 0.074 (95% CI: NE-0.43, P = .01) and one SNP on IL17A (rs4711998), OR = 0.28 (95% CI: 0.078-0.92, P = .034) were independently associated with CR/CRi. None of the analyzed SNPs were associated with CRS. To our knowledge, this is the first study demonstrating a possible association between treatment response to blinatumomab and SNPs. Our hypothesis-generated data suggest a potential role for IL-17 and IL-2 in blinatumomab response and justify a larger confirmatory study, which may lead to personalized blinatumomab immunotherapy for B-ALL.

The Terrible Triad of Checkpoint Inhibition: A Case Report of Myasthenia Gravis, Myocarditis, and Myositis Induced by Cemiplimab in a Patient with Metastatic Cutaneous Squamous Cell Carcinoma.

BACKGROUND: We report a case of a patient with squamous cell carcinoma (SCC) who developed myasthenia gravis (MG), myositis, and myocarditis after receiving cemiplimab, an anti-PD-1 immune checkpoint inhibitor (ICI). Case Presentation. An 86-year-old man with metastatic periocular SCC presented with decreased vision in the left eye, severe fatigue, and lower back and bilateral hip pain 3 weeks after receiving cemiplimab. Within hours, he developed dysphonia, pharyngeal secretions, and dysphagia, necessitating intubation. Endomyocardial biopsy revealed active lymphocyte-mediated necrosis consistent with ICI-induced myocarditis. Anti-striated muscle and anti-acetylcholine receptor antibodies were elevated, consistent with myositis and myasthenia gravis. Despite plasma exchange therapy, steroids, and intravenous immunoglobulin, he died from cardiac arrest. CONCLUSIONS: The presence of myasthenia gravis, myocarditis, or myositis should prompt evaluation for all three toxicities as they may represent an overlap syndrome. The severity of these immunotoxicities highlights the need for clinicians to suspect multiple simultaneous adverse effects of ICIs.

Impact of Cytomegalovirus Viral Load on Probability of Spontaneous Clearance and Response to Preemptive Therapy in Allogeneic Stem Cell Transplantation Recipients.

The optimal viral load threshold at which to initiate preemptive cytomegalovirus (CMV) therapy in hematopoietic cell transplantation (HCT) recipients remains to be defined. In an effort to address this question, we conducted a retrospective study of 174 allogeneic HCT recipients who underwent transplantation at a single center between August 2012 and April 2016. During this period, preemptive therapy was initiated at the discretion of the treating clinician. A total of 109 patients (63%) developed CMV viremia. The median time to reactivation was 17 days (interquartile range, IQR, 7-30 days) post-HCT. A peak viremia ≥150 IU/mL was strongly associated with a reduced probability of spontaneous clearance (relative risk, .16; 95% confidence interval, .1-.27), independent of established clinical risk factors, including CMV donor serostatus, exposure to antithymocyte globulin, and underlying lymphoid malignancy. The median time to clearance of viremia was significantly shorter in those who started therapy at CMV <350 IU/mL (19 days; IQR, 11-35 days) compared with those who started antiviral therapy at higher viremia thresholds (33 days; IQR, 21-42 days; P = .02). The occurrence of treatment-associated cytopenias was frequent but similar in patients who started preemptive therapy at CMV <350 IU/mL and those who started at CMV >350 IU/mL (44% versus 57%; P = .42). Unresolved CMV viremia by treatment day 35 was associated with increased risk of therapeutic failure (32% versus 0%; P = .001). Achieving eradication of CMV viremia by treatment day 35 was associated with a 74% reduction in 1-year nonrelapse mortality (NRM) (adjusted hazard ratio [HR], .26; 95% confidence interval [CI], .1-.8; P = .02), whereas therapeutic failure was associated with a significant increase in the probability of 1-year NRM (adjusted HR, 26; 95% CI, 8-87; P <.0001). We conclude that among allogeneic HCT patients, a peak CMV viremia ≥150 IU/mL is associated with a >80% reduction in the probability of spontaneous clearance independent of ATG administration, CMV donor serostatus, and lymphoid malignancy, and is a reasonable cutoff for preemptive therapy. Delaying initiation of therapy until a CMV value ≥350 IU/mL is associated with more protracted CMV viremia, and unresolved viremia by treatment day 35 is associated with a significant increase in NRM.

Barriers to the universal adoption of bilateral internal mammary artery grafting.

The left internal mammary artery (LIMA) graft is considered the "gold standard" of coronary artery bypass grafting (CABG). This conduit provides increased survival, symptomatic relief, increased freedom from myocardial infarction, and increased freedom from re-intervention when compared to saphenous venous grafting. It has a remarkable long term patency rate with clinical and angiographic outcomes that are unmatched by other conduits. Given the fact that patients often require more than one graft during a coronary revascularization procedure, the prospect of bilateral internal mammary artery (BIMA) grafting has been very appealing to some surgeons. BIMA grafting has been extensively studied via multiple retrospective and prospective cohort studies and findings have indicated that BIMA grafting can have an increased survival benefit when compared to LIMA grafting alone. As a result, this technique has accrued increasing popularity over the course of the last decade. Yet, questions still remain on whether BIMA grafting is the optimal treatment modality for patients in terms of long-term prognosis. There is limited data at the present time from randomized controlled trials and only 4-12% of CABGs performed today utilize BIMA grafting. Concerns regarding perioperative complications, which patient subsets are at higher risks for complications from the technique, and the technical challenges involved in utilizing and teaching the technique have limited its widespread use.