ABSTRACT
Indolent B-cell non-Hodgkin lymphoma (iNHL) patients generally require treatment but experience normal survival, emphasizing the need for simpler, safer therapies. Proteasome inhibitors target aberrant signaling pathways within iNHL and have manageable toxicities. We evaluated the oral proteasome inhibitor ixazomib as initial monotherapy, and combined with rituximab, for first-line treatment of iNHL. Treatment-naïve iNHL patients needing therapy received oral ixazomib 4 mg weekly until progressive disease or unacceptable adverse events. A 4-week course of rituximab was added during month 7. The primary endpoint was overall response rate (ORR) during the ixazomib monotherapy window. Correlates included gene expression profiling and response to SARS-CoV-2 vaccination. Thirty-three patients with follicular lymphoma (FL) (n=20), marginal zone lymphoma (n=7), and other iNHL were treated with median follow-up of 30.3 months. During the 6-month ixazomib window the ORR was 24%, including 35% in FL. Best ORR over the entire study period was 52% overall and 65% in FL; CR was achieved in 33% and 45%, respectively. The median duration of response was 25.8 months (range, 0 - 49.7), and the 24-month progression-free and overall survival were 51% (95% CI 32-67%) and 91% (95% CI 74-97%). Ixazomib was well-tolerated. Baseline downregulation of proteasome genes PSMB9 (P = 0.03) and PSMB8 (P = 0.007) were associated with response. All evaluated patients generated anti-S antibodies to SARS-CoV-2 vaccination, median 254.9 BAU/mL. Ixazomib demonstrated efficacy alone and with short course rituximab in untreated iNHL while exhibiting favorable toxicity, convenience, and retention of B-cell immune response. This trial is registered at www.clinicaltrials.gov as NCT02339922.
ABSTRACT
Prior publications have demonstrated low rates of seroconversion to the SARS-CoV-2 mRNA vaccines in patients with chronic lymphocytic leukemia (CLL). In this national collaboration of 11 cancer centers around the United States, we aimed to further characterize and understand the vaccine-induced immune response, including T-cell responses and the impact of CLL therapeutics (NCT04852822). Eligible patients were enrolled into two cohorts: 1) at the time of the initial vaccination and 2) at the time of booster vaccination. Serologic response rates (anti-S) from the 210 patients in the initial vaccination cohort and 117 in the booster vaccination cohort were 56% (95% CI, 50-63%) and 68% (95% CI, 60-77%), respectively. Compared to patients not on therapy, those receiving B-cell-directed therapy were less likely to seroconvert (OR 0.27, 95% CI 0.15-0.49). Persistence of response was seen at 6 months;anti-S titers increased with administration of booster vaccinations. In the initial vaccination cohort, positive correlations were seen between quantitative serologic response and CD4 T-cell response for the Wuhan variant and to a lesser degree, for the Omicron variant (Spearman ρ = 0.45 for Wuhan, ρ = 0.25 for Omicron). In the booster vaccination cohort, positive correlations were seen between serologic response and CD4 T-cell responses for both variants (ρ = 0.58 Wuhan, ρ= 0.57 Omicron) and to a lesser degree for CD8 T-cell responses (ρ = 0.33 Wuhan, ρ = 0.22 Omicron). While no deaths from COVID-19 were reported after booster vaccinations, patients should use caution as newer variants emerge and escape vaccine-induced immunity.
ABSTRACT
Prior publications have demonstrated low rates of seroconversion to the SARS-CoV-2 mRNA vaccines in patients with chronic lymphocytic leukemia (CLL). In this national collaboration of 11 cancer centers around the United States, we aimed to further characterize and understand the vaccine-induced immune response, including T-cell responses and the impact of CLL therapeutics (NCT04852822). Eligible patients were enrolled into two cohorts: 1) at the time of the initial vaccination and 2) at the time of booster vaccination. Serologic response rates (anti-S) from the 210 patients in the initial vaccination cohort and 117 in the booster vaccination cohort were 56% (95% CI, 50-63%) and 68% (95% CI, 60-77%), respectively. Compared to patients not on therapy, those receiving B-cell-directed therapy were less likely to seroconvert (OR 0.27, 95% CI 0.15-0.49). Persistence of response was seen at 6 months; anti-S titers increased with administration of booster vaccinations. In the initial vaccination cohort, positive correlations were seen between quantitative serologic response and CD4 T-cell response for the Wuhan variant and to a lesser degree, for the Omicron variant (Spearman P = 0.45 for Wuhan, P = 0.25 for Omicron). In the booster vaccination cohort, positive correlations were seen between serologic response and CD4 T-cell responses for both variants (P = 0.58 Wuhan, P = 0.57 Omicron) and to a lesser degree for CD8 T-cell responses (P = 0.33 Wuhan, P = 0.22 Omicron). While no deaths from COVID-19 were reported after booster vaccinations, patients should use caution as newer variants emerge and escape vaccine-induced immunity.