Efficacy and safety profile of COVID-19 vaccine in cancer patients: a prospective, multicenter cohort study.

Aim: To compare the seropositivity rate of cancer patients with noncancer controls after inactive SARS-CoV-2 vaccination and evaluate the factors affecting seropositivity. Method: Spike IgG antibodies against SARS-CoV-2 were measured in blood samples of 776 cancer patients and 715 noncancer volunteers. An IgG level ≥50 AU/ml is accepted as seropositive. Results: The seropositivity rate was 85.2% in the patient group and 97.5% in the control group. The seropositivity rate and antibody levels were significantly lower in the patient group (p < 0.001). Age and chemotherapy were associated with lower seropositivity in cancer patients (p < 0.001). Conclusion: This study highlighted the efficacy and safety of the inactivated vaccine in cancer patients. Clinical Trials Registration: NCT04771559 (ClinicalTrials.gov).

Cancer patients are at high risk for infection with SARS-CoV-2 and of developing the associated disease, COVID-19, which therefore puts them in the priority group for vaccination. This study evaluated the efficacy and safety of inactive SARSCoV-2 vaccination, an inactivated virus vaccine, in cancer patients. The immune response rate, defined as seropositivity, was 85.2% in the cancer patient group and 97.5% in the control group. The levels of antibodies, which are blood markers of immune response to the vaccine, were also significantly lower in the patient group, especially in those older than 60 years and receiving chemotherapy. These results highlight the importance of determining the effective vaccine type and dose in cancer patients to protect them from COVID-19 without disrupting their cancer treatment.

Clinical Experience with [225Ac]Ac-PSMA Treatment in Patients with [177Lu]Lu-PSMA-Refractory Metastatic Castration-Resistant Prostate Cancer.

For patients with advanced-stage metastatic castration-resistant prostate cancer (mCRPC) who do not respond to [177Lu]Lu-PSMA therapy, there are limited treatment options. Clinical results obtained with [225Ac]Ac-PSMA are promising. We retrospectively analyzed the outcomes of patients treated with [225Ac]Ac-PSMA between December 2018 and October 2022. Methods: We evaluated the treatment results of 23 patients (mean age, 70.3 ± 8.8 y) with mCRPC who were refractory to treatment with [177Lu]Lu-PSMA (2-9 cycles). The safety profile was assessed according to Common Technology Criteria for Adverse Events version 5.0. Treatment efficacy was assessed using prostate-specific membrane antigen PET progression criteria and prostate-specific antigen (PSA) response according to Prostate Cancer Working Group 2 criteria after the first cycle of [225Ac]Ac-PSMA treatment. Results: All patients received androgen-deprivation therapy, whereas 22 (96%) and 19 (83%) patients received chemotherapy and second-generation antiandrogen therapy, respectively. One patient received 4 cycles, 2 received 3 cycles, 8 received 2 cycles, and 12 received 1 cycle of [225Ac]Ac-PSMA. The median interval between cycles was 13 wk (range, 8-28 wk). [225Ac]Ac-PSMA was administered with a mean activity of 7.6 MBq (range, 6.2-10.0 MBq) in each cycle. Patients were at an advanced stage of disease, and tumor burden was very high. Although the best PSA response was observed in 5 patients (26%) after [225Ac]Ac-PSMA treatment, there was at least some level of decline in PSA observed in 11 patients (58%; n = 19). Treatment response was assessed in patients who underwent [68Ga]Ga-PSMA PET/CT imaging. After the first cycle of treatment (n = 18), 50% of patients (n = 9) showed disease progression according to prostate-specific membrane antigen PET progression criteria, and the disease control rate was calculated to be 50%. Median progression-free survival was 3.1 mo, and median overall survival was 7.7 mo. Grade 3 hematologic toxicity occurred in 1 patient, and grade 3 nephrotoxicity was observed in another patient. Parotid SUVmax decreased by 33%, although all patients complained of dry mouth before treatment. Conclusion: We observed that [225Ac]Ac-PSMA therapy was safe and showed potential even in cases with advanced-stage mCRPC in which all other treatment options were completed.