Humoral and cellular immunogenicity of SARS-CoV-2 vaccines in chronic lymphocytic leukemia: a prospective cohort study.

Chronic lymphocytic leukemia (CLL), the most common leukemia worldwide, is associated with increased COVID-19 mortality. Previous studies suggest only a portion of vaccinated CLL patients develop severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike antibodies. Whether the elicited antibodies are functional and/or accompanied by functional T-cell responses is unknown. This prospective cohort study included patients with CLL who received SARS-CoV-2 and PCV13 vaccines (not concurrently). The primary cohort included adults with CLL off therapy. Coprimary outcomes were serologic response to SARS-CoV-2 (receptor binding domain [RBD] immunoassay) and PCV13 vaccines (23-serotype IgG assay). Characterization of SARS-CoV-2 antibodies and their functional activity and assessment of functional T-cell responses was performed. Sixty percent (18/30) of patients demonstrated serologic responses to SARS-CoV-2 vaccination, appearing more frequent among treatment-naïve patients (72%). Among treatment-naïve patients, an absolute lymphocyte count ≤24 000/µL was associated with serologic response (94% vs 14%; P < .001). On interferon-γ release assays, 80% (16/20) of patients had functional spike-specific T-cell responses, including 78% (7/9) with a negative RBD immunoassay, a group enriched for prior B-cell-depleting therapies. A bead-based multiplex immunoassay identified antibodies against wild-type and variant SARS-CoV-2 (α, ß, γ, and δ) in all tested patients and confirmed Fc-receptor binding and effector functions of these antibodies. Of 11 patients with negative RBD immunoassay after vaccination, 6 (55%) responded to an additional mRNA-based vaccine dose. The PCV13 serologic response rate was 29% (8/28). Our data demonstrate that SARS-CoV-2 vaccination induces functional T-cell and antibody responses in patients with CLL and provides the framework for investigating the molecular mechanisms and clinical benefit of these responses. This trial was registered at www.clinicaltrials.gov as #NCT05007860.

A multicenter study of romiplostim for chemotherapy-induced thrombocytopenia in solid tumors and hematologic malignancies.

Chemotherapy-induced thrombocytopenia (CIT) frequently complicates cancer treatment causing chemotherapy delays, dose reductions, and discontinuation. There is no FDA-approved agent available to manage CIT. This study retrospectively evaluated patients with CIT treated on institutional romiplostim treatment pathways at 4 U.S. centers. The primary outcome was achievement of a romiplostim response [median on-romiplostim platelet count (Plt) ≥75x109/L and ≥30x109/L above baseline]. Secondary outcomes included time to Plt≥100x109/L and rates of the following: Plt<100x109/L, Plt<75x109/L, Plt<50x109/L, thrombocytosis, chemotherapy dose reduction/treatment delay, platelet transfusion, bleeding, and thromboembolism. Multivariable regression was used to identify predictors of romiplostim non-response and compare weekly dosing with intracycle/intermittent dosing. 173 patients (153 solid tumor, 20 lymphoma or myeloma) were treated, with 170 (98%) receiving a median of 4 (range, 1-36) additional chemotherapy cycles on romiplostim. Romiplostim was effective in solid tumor patients: 71% of patients achieved a romiplostim response, 79% avoided chemotherapy dose reductions/treatment delays and 89% avoided platelet transfusions. Median per-patient Plt on romiplostim was significantly higher than baseline (116x109/L vs. 60x109/L, P<0.001). Bone marrow tumor invasion, prior pelvic irradiation, and prior temozolomide predicted romiplostim non-response. Bleeding rates were lower than historical CIT cohorts and thrombosis rates were not elevated. Weekly dosing was superior to intracycle dosing with higher response rates and less chemotherapy dose reductions/treatment delays (IRR 3.00, 95% CI 1.30-6.91, P=0.010) or bleeding (IRR 4.84, 95% CI 1.18-19.89, P=0.029). Blunted response (10% response rate) was seen in non-myeloid hematologic malignancy patients with bone marrow involvement. In conclusion, romiplostim was safe and effective for CIT in most solid tumor patients.

A Clinical Prediction Model to Assess Risk for Chemotherapy-Related Hospitalization in Patients Initiating Palliative Chemotherapy.

IMPORTANCE: Chemotherapy-related hospitalizations in patients with advanced cancer are common, distressing, and costly. Methods to identify patients at high risk of chemotherapy toxic effects will permit development of targeted strategies to prevent chemotherapy-related hospitalizations. OBJECTIVE: To demonstrate the feasibility of using readily available clinical data to assess patient-specific risk of chemotherapy-related hospitalization. DESIGN, SETTING, AND PARTICIPANTS: Nested case-control study conducted from January 2003 through December 2011 at the Mass General/North Shore Cancer Center, a community-based cancer center in northeastern Massachusetts. The parent cohort included 1579 consecutive patients with advanced solid-tumor cancer receiving palliative-intent chemotherapy. Case patients (n = 146) included all patients from the parent cohort who experienced a chemotherapy-related hospitalization. Controls (n = 292) were randomly selected from 1433 patients who did not experience a chemotherapy-related hospitalization. EXPOSURES: Putative risk factors for chemotherapy-related hospitalization-including patient characteristics, treatment characteristics, and pretreatment laboratory values-were abstracted from medical records. Multivariable logistic regression was used to model the patient-specific risk of chemotherapy-related hospitalization. MAIN OUTCOMES AND MEASURES: Chemotherapy-related hospitalization, as adjudicated by the oncology clinical care team within a systematic quality-assessment program. RESULTS: A total of 146 (9.2%) of 1579 patients from the parent cohort experienced a chemotherapy-related hospitalization. In multivariate regression, 7 variables were significantly associated with chemotherapy-related hospitalization: age, Charlson comorbidity score, creatinine clearance, calcium level, below-normal white blood cell and/or platelet count, polychemotherapy (vs monotherapy), and receipt of camptothecin chemotherapy. The median predicted risk of chemotherapy-related hospitalization was 6.0% (interquartile range [IQR], 3.6%-11.4%) in control patients and 14.7% (IQR, 6.8%-22.5%) in case patients. The bootstrap-adjusted C statistic was 0.71 (95% CI, 0.66-0.75). At a risk threshold of 15%, the model exhibited a sensitivity of 49% (95% CI, 41%-57%) and a specificity of 85% (95% CI, 81%-89%) for predicting chemotherapy-related hospitalization. CONCLUSIONS AND RELEVANCE: In patients initiating palliative chemotherapy for cancer, readily available clinical data were associated with the patient-specific risk of chemotherapy-related hospitalization. External validation and evaluation in the context of a clinical decision support tool are warranted.