Indolent lymphoma care delivery and outcomes during the COVID-19 pandemic in Ontario, Canada.

The treatment pattern and outcomes in patients with indolent B-cell lymphoma treated during the coronavirus disease 2019 (COVID-19) pandemic period compared to the prepandemic period are unclear. This was a retrospective population-based study using administrative databases in Ontario, Canada (follow-up to 31 March 2022). The primary outcome was treatment pattern; secondary outcomes were death, toxicities, healthcare utilization (emergency department [ED] visit, hospitalization) and SARS-CoV-2 outcomes. Adjusted hazard ratios (aHR) from Cox proportional hazards models were used to estimate associations. We identified 4143 patients (1079 pandemic, 3064 prepandemic), with a median age of 69 years. In both time periods, bendamustine (B) + rituximab (BR) was the most frequently prescribed regimen. During the pandemic, fewer patients received R maintenance or completed the full 2-year course (aHR 0.81, 95% CI 0.71-0.92, p = 0.001). Patients treated during the pandemic had less healthcare utilization (ED visit aHR 0.77, 95% CI 0.68, 0.88, p < 0.0001; hospitalization aHR 0.81, 95% CI 0.70-0.94, p = 0.0067) and complications (infection aHR 0.69, 95% CI 0.57-0.82, p < 0.0001; febrile neutropenia aHR 0.66, 95% CI 0.47-0.94, p = 0.020), with no difference in death. Independent of vaccination, active rituximab use was associated with a higher risk of COVID-19 complications. Despite similar front-line regimen use, healthcare utilization and admissions for infection were less in the pandemic cohort.

Fracture risk among patients with cancer compared to individuals without cancer: a population-based study.

BACKGROUND: Patients with cancer may be at increased risk of osteoporosis and fracture; however, gaps exist in the existing literature and the association between cancer and fracture requires further examination. METHODS: We conducted a population-based cohort study of Ontario patients with cancer (breast, prostate, lung, gastrointestinal, haematologic) diagnosed between January 2007 to December 2018 and 1:1 matched non-cancer controls. The primary outcome was incident fracture (end of follow-up December 2019). Multivariable Cox regression analysis was used to estimate the relative fracture risk with sensitivity analysis accounting for competing risk of death. RESULTS: Among 172,963 cancer patients with non-cancer controls, 70.6% of patients with cancer were <65 years old, 58% were female, and 9375 and 8141 fracture events were observed in the cancer and non-cancer group, respectively (median follow-up 6.5 years). Compared to non-cancer controls, patients with cancer had higher risk of fracture (adjusted HR [aHR] 1.10, 95% CI 1.07-1.14, p < 0.0001), which was also observed for both solid (aHR 1.09, 95% CI 1.05-1.13, p < 0.0001) and haematologic cancers (aHR 1.20, 95% CI 1.10-1.31, p < 0.0001). Sensitivity analysis accounting for competing risk of death did not change these findings. CONCLUSIONS: Our study indicates that patients with cancer are at modest risk of fractures compared to non-cancer controls.

Outcomes of patients with hematologic malignancies and COVID-19: a systematic review and meta-analysis of 3377 patients.

Outcomes for patients with hematologic malignancy infected with COVID-19 have not been aggregated. The objective of this study was to perform a systematic review and meta-analysis to estimate the risk of death and other important outcomes for these patients. We searched PubMed and EMBASE up to 20 August 2020 to identify reports of patients with hematologic malignancy and COVID-19. The primary outcome was a pooled mortality estimate, considering all patients and only hospitalized patients. Secondary outcomes included risk of intensive care unit admission and ventilation in hospitalized patients. Subgroup analyses included mortality stratified by age, treatment status, and malignancy subtype. Pooled prevalence, risk ratios (RRs), and 95% confidence intervals (CIs) were calculated using a random-effects model. Thirty-four adult and 5 pediatric studies (3377 patients) from Asia, Europe, and North America were included (14 of 34 adult studies included only hospitalized patients). Risk of death among adult patients was 34% (95% CI, 28-39; N = 3240) in this sample of predominantly hospitalized patients. Patients aged ≥60 years had a significantly higher risk of death than patients <60 years (RR, 1.82; 95% CI, 1.45-2.27; N = 1169). The risk of death in pediatric patients was 4% (95% CI, 1-9; N = 102). RR of death comparing patients with recent systemic anticancer therapy to no treatment was 1.17 (95% CI, 0.83-1.64; N = 736). Adult patients with hematologic malignancy and COVID-19, especially hospitalized patients, have a high risk of dying. Patients ≥60 years have significantly higher mortality; pediatric patients appear to be relatively spared. Recent cancer treatment does not appear to significantly increase the risk of death.

Association between diabetes and haematological malignancies: a population-based study.

AIMS/HYPOTHESIS: Contemporary data for the association of diabetes with haematological malignancies are lacking. We evaluated the risk of developing haematological malignancies and subsequent mortality in individuals with diabetes compared with those without diabetes. METHODS: We conducted a population-based observational study using healthcare databases from Ontario, Canada. All Ontario residents 30 years of age or older free of cancer and diabetes between 1 January 1996 and 31 December 2015 were eligible for inclusion. Using Cox regression analyses, we explored the association between diabetes and the risk and mortality of haematological malignancies (leukaemia, lymphoma, multiple myeloma). The impact of timing on associations was evaluated with analyses stratified by time since diabetes diagnosis (<3 months, 3 months to 1 year, ≥1 year). RESULTS: We identified 1,003,276 individuals with diabetes and age and sex matched these to 2,006,552 individuals without diabetes. Compared with individuals without diabetes, those with diabetes had a modest but significantly higher risk of a haematological malignancy (adjusted HR 1.10 [95% CI 1.08, 1.12] p < 0.0001). This association persisted across all time periods since diabetes diagnosis. Among those with haematological malignancies, diabetes was associated with a higher all-cause mortality (HR 1.36 [95% CI 1.31, 1.41] p < 0.0001) compared with no diabetes, as well as cause-specific mortality. CONCLUSIONS/INTERPRETATION: Diabetes is associated with a higher risk of haematological malignancies and is an independent risk factor of all-cause and cause-specific mortality. Greater efforts for lifestyle modification may not only reduce diabetes burden and its complications but may also potentially lower risk of malignancy and mortality. Graphical abstract.

Levothyroxine dose and risk of atrial fibrillation: A nested case-control study.

Contemporary data on the effect of levothyroxine dose on the occurrence of atrial fibrillation (AF) are lacking, particularly in the older population. Our objective was to determine the effect of cumulative levothyroxine exposure on risk of AF and ischemic stroke in older adults. METHODS: We conducted a population-based observational study using health care databases from Ontario, Canada. We identified adults aged ≥66 years without a history of AF who filled at least 1 levothyroxine prescription between April 1, 2007, and March 31, 2016. Cases were defined as cohort members who had incident AF (emergency room visit or hospitalization) between the date of first levothyroxine prescription and December 31, 2017. Index date was date of AF. Cases were matched with up to 5 controls without AF on the same index date. Secondary outcome was ischemic stroke. Cumulative levothyroxine exposure was estimated based on total milligrams of levothyroxine dispensed in the year prior to index date. Using nested case-control approach, we compared outcomes between older adults who received high (≥0.125 mg/d), medium (0.075-0.125 mg/d), or low (0-0.075 mg/d) cumulative levothyroxine dose. We compared outcomes between current, recent past, and remote past levothyroxine use. RESULTS: Of 183,360 older adults treated with levothyroxine (mean age 82 years; 72% women), 30,560 (16.1%) had an episode of AF. Compared to low levothyroxine exposure, high and medium exposure was associated with significantly increased risk of AF after adjustment for covariates (adjusted odds ratio [aOR] 1.29, 95% CI 1.23-1.35; aOR 1.08, 95% CI 1.04-1.11; respectively). No association was observed between levothyroxine exposure and ischemic stroke. Compared with current levothyroxine use, older adults with remote levothyroxine use had lower risks of AF (aOR 0.56, 95% CI 0.52-0.59) and ischemic stroke (aOR 0.61, 95% CI 0.56-0.67). CONCLUSIONS: Among older persons treated with levothyroxine, levothyroxine at doses >0.075 mg/d is associated with an increased risk of AF compared to lower exposure.

Comparison of outcomes in a population-based cohort of metastatic breast cancer patients receiving anti-HER2 therapy with clinical trial outcomes.

PURPOSE: Little data exist for comparing cardiac safety and survival outcomes of trastuzumab/pertuzumab or ado-T emtansine (TDM1) in metastatic breast cancer (MBC) patients enrolled in randomized clinical trial (RCT) vs the real-world. METHODS: This was a retrospective population-based cohort of all patients with MBC treated with trastuzumab/pertuzumab or TDM1 (2012-2017) in Ontario, Canada. Outcomes were incident heart failure (HF) and overall survival (OS). RCT data were obtained from digitizing survival curves and compared with cohort data using Kaplan-Meier analysis. Age-based comparison of outcomes was conducted for patients ≥ 65 years old vs younger than 65. RESULTS: The two cohorts composed of 833 and 397 patients treated with trastuzumab/pertuzumab and TDM1, of whom 5.5% and 7.6% had baseline HF, respectively. Incident HF following trastuzumab/pertuzumab or TDM1 was low (trastuzumab/pertuzumab 1.8 events/100 person years; TDM1 0.02 events/100 person years). The median OS was 39.2 and 56.4 months in the trastuzumab/pertuzumab population-based cohort and CLEOPATRA, respectively. The median OS was 15.4 and 30.9 months in the TDM1 population-based cohort and EMILIA, respectively. Cohort OS was significantly worse than RCT OS (trastuzumab/pertuzumab HR 1.67, 95% CI 1.37-2.03, p < 0.0001; TDM1 HR 2.80, 95% CI 2.27-3.44, p < 0.0001). Older patients had worse OS than younger patients for trastuzumab/pertuzumab (HR 1.60, 95% CI 1.19-2.16, p = 0.0018), but not for TDM1 (HR 1.16, 95% CI 0.81-1.66, p = 0.43). CONCLUSION: HF incidence during trastuzumab/pertuzumab or TDM1 therapy in this real-world cohort was low. Survival in this cohort was worse compared to RCT, suggesting that recruitment of patients similar to the real-world population is required.

Temporal changes in treatments and outcomes after acute myocardial infarction among cancer survivors and patients without cancer, 1995 to 2013.

BACKGROUND: There is a paucity of information about treatment and mortality trends after acute myocardial infarction (AMI) for cancer survivors (CS). METHODS: In this population-based study, the authors compared temporal trends of treatments and outcomes (mortality, nonfatal cardiovascular outcomes), among CS and patients without cancer (the noncancer patient [NCP] group) with AMI in Ontario (Canada) using inverse probability treatment weight (IPTW)-adjusted modeling. RESULTS: Of 270,089 patients with AMI (22,907 CS, 247,182 NCP, 1995-2013; median follow-up, 10.1 and 11.0 years, respectively), the use of invasive coronary strategies and pharmacotherapies increased and mortality declined for CS and NCP (all Ptrend < .001). At 30 days after AMI, there was no difference between CS and NCP in the receipt of coronary angiography (incidence risk ratio [IRR], 0.98; 95% confidence interval [CI], 0.96-1.01; P = .23), percutaneous coronary intervention (IRR, 0.98; 95% CI, 0.94-1.02; P = .29), or bypass (IRR, 0.93; 95% CI, 0.85-1.02; P = .11). At 90 days after AMI, there was no difference in the receipt of ß-blockers, clopidogrel, or nitrates; but CS were less often prescribed angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers and statins. CS had higher all-cause mortality at 30 days (adjusted hazard ratio [HR] 1.12; 95% CI, 1.07-1.17; P < .001), at 1 year (1.16; 95% CI, 1.12-1.20; P < .001), and long term (HR, 1.21; 95% CI, 1.17-1.25; P < .001) and had a greater risk of heart failure (HR, 1.08; 95% CI, 1.03-1.14; P = .001), but not myocardial re-infarction (HR, 0.98; 95% CI, 0.95-1.01; P = .22) or stroke (HR, 1.06; 95% CI, 0.97-1.16; P = .18). CONCLUSIONS: Among CS and NCP with AMI in Ontario, similar improvements in mortality and receipt of treatments were observed between 1995 and 2013. However, compared with NCP, CS had a higher risk of mortality and heart failure. Cancer 2018;124:1269-78. © 2017 American Cancer Society.

Cardiovascular magnetic resonance left ventricular strain in end-stage renal disease patients after kidney transplantation.

BACKGROUND: Cardiovascular disease is a significant cause of morbidity and mortality in patients with end-stage renal disease (ESRD) and kidney transplant (KT) patients. Compared with left ventricular (LV) ejection fraction (LVEF), LV strain has emerged as an important marker of LV function as it is less load dependent. We sought to evaluate changes in LV strain using cardiovascular magnetic resonance imaging (CMR) in ESRD patients who received KT, to determine whether KT may improve LV function. METHODS: We conducted a prospective multi-centre longitudinal study of 79 ESRD patients (40 on dialysis, 39 underwent KT). CMR was performed at baseline and at 12 months after KT. RESULTS: Among 79 participants (mean age 55 years; 30% women), KT patients had significant improvement in global circumferential strain (GCS) (p = 0.007) and global radial strain (GRS) (p = 0.003), but a decline in global longitudinal strain (GLS) over 12 months (p = 0.026), while no significant change in any LV strain was observed in the ongoing dialysis group. For KT patients, the improvement in LV strain paralleled improvement in LVEF (57.4 ± 6.4% at baseline, 60.6% ± 6.9% at 12 months; p = 0.001). For entire cohort, over 12 months, change in LVEF was significantly correlated with change in GCS (Spearman's r = - 0.42, p < 0.001), GRS (Spearman's r = 0.64, p < 0.001), and GLS (Spearman's r = - 0.34, p = 0.002). Improvements in GCS and GRS over 12 months were significantly correlated with reductions in LV end-diastolic volume index and LV end-systolic volume index (all p < 0.05), but not with change in blood pressure (all p > 0.10). CONCLUSIONS: Compared with continuation of dialysis, KT was associated with significant improvements in LV strain metrics of GCS and GRS after 12 months, which did not correlate with blood pressure change. This supports the notion that KT has favorable effects on LV function beyond volume and blood pessure control. Larger studies with longer follow-up are needed to confirm these findings.

Long-term cardiovascular outcomes and overall survival of early-stage breast cancer patients with early discontinuation of trastuzumab: a population-based study.

We critically examined long-term cardiovascular (CV) outcomes and overall survival (OS) of breast cancer (BC) patients who had cardiotoxicity during adjuvant trastuzumab treatment requiring discontinuation in a population-based sample. This was a retrospective cohort of early-stage BC patients diagnosed before 2010 and treated with trastuzumab in Ontario. Patients were stratified based on trastuzumab doses received: 1-8, 9-15, ≥16 (therapy completion). Time-dependent multivariable Cox models were used to analyze primary endpoint OS, and the following composite endpoints: hospitalization/emergency room visit for heart failure (HF) or death; non-HF CV (myocardial infarction, stroke) or death; and clinically significant relapse (palliative systemic therapy initiation >90 days after last trastuzumab dose) or death. Of the 3134 women, 6, 10, and 85 % received 1-8, 9-15, and ≥16 doses, respectively. Over 5-year median follow-up, early trastuzumab discontinuation was associated with more HF/death [1-8 doses hazard ratio (HR) 4.0, 95 % confidence interval (CI) 2.7-6.0; 9-15 doses HR 2.97, 95 % CI 2.1-4.3], non-HF/death (1-8 doses HR 4.3, 95 % CI 3.0-6.1; 9-15 doses HR 3.1, 95 % CI 2.2-4.4), clinically significant relapse/death (1-8 doses HR 3.1, 95 % CI 2.2-4.4; 9-15 doses HR 2.4, 95 % CI 1.8-3.3), and importantly lower OS (77, 80, 93 %; P < 0.001). Early discontinuation (1-8 doses HR 2.41, 95 % CI 1.5-3.8; 9-15 doses HR 2.9, 95 % CI 2.0-4.1) and clinically significant relapse (HR 34.0, 95 % CI 24.9-46.6) were both independent predictors of mortality. Of note, early discontinuation remained a critical independent predictor of OS even after adjusting for incident HF. Early trastuzumab discontinuation is a powerful independent predictor of cardiac events and clinically significant relapse, and both may contribute to poor survival. Both adequate cancer control and optimal CV management are required to improve long-term outcomes.

The impact of marginalization on diffuse large B-cell lymphoma overall survival: a retrospective cohort study.

The aim of this study was to describe the impact of marginalization on DLBCL overall survival (OS) within the Canadian setting. We conducted a population-based retrospective cohort study of adult patients with newly diagnosed DLBCL in Ontario between 1 January 2005 and 31 December 2017 receiving a rituximab-containing chemotherapy regimen with curative intent followed until 1 March 2020. Our primary exposure of interest was the Ontario Marginalization Index (ON-Marg). The primary outcome was 2-year OS, accounting for patient age, sex, cancer characteristics, comorbidity burden, and rural dwelling status. While two-year overall survival was inferior for individuals in the most deprived marginalization quintile (70.4% Q5 vs. 76.0% Q1), after adjustment for relevant covariates neither the composite ON-Marg nor any of its dimensions had a significant effect. Within the Canadian context, among patients who receive chemotherapy, marginalization may not have a significant association with overall survival when accounting for key patient covariates, lending support for preserved outcomes.

Temporal Trends of Enrollment by Sex and Race in Major Cardiovascular Randomized Clinical Trials.

Background: Women and racialized minorities continue to be underrepresented in cardiovascular (CV) trial outcomes data, despite comprising a significant global burden of CV disease. This study evaluated the impact of trial characteristics on the temporal enrollment of women and racialized minorities in prominent CV trials published in the period 1986-2023. Methods: MEDLINE was searched for CV trials published in The Lancet, the Journal of the American Medical Association, and the New England Journal of Medicine. Participant and investigator demographics, types of interventions, clinical indications, and funding sources were compared according to the enrollment of women or racialized minorities. Results: From 799 studies, including 4,071,921 patients, the enrollment of women and racialized minorities significantly increased from 1986 to 2023 (both P ≤ 0.001). Although the enrollment of women varied by trial indication, comprising 25.0% of coronary artery disease, 35.2% of noncoronary and/or vascular disease, 13.8% of heart failure, 17.0% of arrhythmia, and 28.7% of other CV trials (P ≤ 0.001), it did not differ by peer-reviewed vs industry funding. First authors who were women were more likely than first authors who were men to enroll significantly more women (P = 0.01). Conclusions: Active efforts to increase diverse enrollment, along with improved reporting, including of sex and race, in future CV trials may increase the generalizability of their findings and applicability to global populations.

Contexte: Les femmes et les groupes racisés demeurent sous-représentés dans les données de résultats d'essais cliniques sur les maladies cardiovasculaires (CV) malgré l'important fardeau global associé à ces maladies. Cette étude visait à évaluer l'effet des caractéristiques des essais sur la sélection temporelle des femmes et des membres de groupes racisés dans les essais portant principalement sur les maladies CV durant la période de 1986 à 2023. Méthodologie: La base de données MEDLINE a été consultée à la recherche d'essais sur les maladies CV publiés dans The Lancet, Journal of the American Medical Association et New England Journal of Medicine. Les données démographiques des participants et des chercheurs, les types d'interventions, les indications cliniques et les sources de financement ont été comparés en fonction de la sélection des femmes ou des membres de groupes racisés. Résultats: Dans 799 études cumulant 4 071 921 patients, la sélection des femmes et des membres de groupes racisés a augmenté significativement entre 1986 et 2023 (p ≤ 0,001 dans les deux cas). Bien que la sélection des femmes variait en fonction des indications des essais, soit 25,0 % dans les essais portant sur les coronaropathies, 35,2 % pour les maladies non coronariennes et/ou vasculaires, 13,8 % pour l'insuffisance cardiaque, 17,0 % pour l'arythmie et 28,7 % pour d'autres maladies CV (p ≤ 0,001), elle ne différait pas selon que les études étaient révisées par des pairs ou qu'elles étaient financées par l'industrie. Lorsqu'une femme était l'autrice principale, le nombre de femmes sélectionnées était susceptible d'être plus élevé que lorsque l'auteur principal était un homme (p = 0,01). Conclusions: Des efforts actifs pour diversifier davantage la sélection des participants et mieux rendre compte des différences, notamment en ce qui concerne le sexe et la race, pourraient élargir la portée des conclusions des futurs essais sur les maladies CV et leur application à l'ensemble de la population.

Determination of clinically therapeutic endoxifen concentrations based on efficacy from human MCF7 breast cancer xenografts.

Tamoxifen is a widely prescribed adjuvant anti-estrogen agent for estrogen receptor-positive breast cancer. Tamoxifen is known to undergo CYP2D6-mediated bioactivation to the active metabolite endoxifen. Endoxifen concentrations exhibit high interindividual variability, contributing to either sub-optimal tamoxifen efficacy or side effects in subsets of patients. However, the relationship between endoxifen exposure and tumor growth inhibition has not been well-characterized and little is known regarding the optimal in vivo endoxifen plasma level required for tumor inhibition. Pharmacokinetics-Pharmacodynamics (PK-PD) modeling was carried out to characterize the relationship between endoxifen concentration and tumor growth inhibition (TGI) in dose-ranging experiments in the human MCF7 xenograft bearing mouse model. Subsequently, simulations using human PK were used to determine the efficacious clinically relevant endoxifen concentration required to produce optimal tumor suppression. Based on the PK-PD model and simulations using clinical PK/concentration data of endoxifen, C stasis (100 % TGI) is observed at 53 nM, a concentration attained by many tamoxifen-treated patients. Importantly, PK-PD simulations indicate that mean steady-state levels observed in CYP2D6 extensive metabolizers are expected to result in optimal tumor suppression while mean concentrations observed in poor metabolizers are predicted to result in suboptimal TGI. Our study is the first to characterize the in vivo PK-PD relationship for endoxifen where clinically observed endoxifen concentrations are associated, in an exposure-dependent manner, with % TGI measured in a xenograft model. It is anticipated that endoxifen concentration achieved in individual patients is the limiting factor for achieving optimal tumor growth suppression.

CYP3A4 and seasonal variation in vitamin D status in addition to CYP2D6 contribute to therapeutic endoxifen level during tamoxifen therapy.

Tamoxifen is a widely utilized adjuvant anti-estrogen agent for hormone receptor-positive breast cancer, known to undergo CYP2D6-mediated bioactivation to endoxifen. However, little is known regarding additional genetic and non-genetic determinants of optimal endoxifen plasma concentration. Therefore, 196 breast cancer patients on tamoxifen were enrolled in this prospective study over a 24-month period. Blood samples were collected for pharmacogenetic and drug-level analysis of tamoxifen and metabolites. Regression analysis indicated that besides CYP2D6, the recently described CYP3A4*22 genotype, seasonal variation, and concomitant use of CYP2D6-inhibiting antidepressants were significant predictors of endoxifen concentration. Of note, genetic variation explained 33 % of the variability while non-genetic variables accounted for 13 %. Given the proposed notion of a sub-therapeutic endoxifen concentration for predicting breast cancer recurrence, we set the therapeutic threshold at 18 nM, the 20th percentile for endoxifen level among enrolled patients in this cohort. Nearly 70 % of CYP2D6 poor metabolizers as well as extensive metabolizers on potent CYP2D6-inhibiting antidepressants exhibited endoxifen levels below 18 nM, while carriers of CYP3A4*22 were twofold less likely to be in sub-therapeutic range. Unexpectedly, endoxifen levels were 20 % lower during winter months than mean levels across seasons, which was also associated with lower vitamin D levels. CYP3A4*22 genotype along with sunshine exposure and vitamin D status may be unappreciated contributors of tamoxifen efficacy. The identified covariates along with demographic variables were integrated to create an endoxifen concentration prediction algorithm to pre-emptively evaluate the likelihood of individual patients falling below the optimal endoxifen concentration.

Prospective evaluation of a pharmacogenetics-guided warfarin loading and maintenance dose regimen for initiation of therapy.

Single-nucleotide polymorphisms in genes that affect warfarin metabolism (cytochrome P450 2C9 gene, CYP2C9) and response (vitamin K epoxide reductase complex 1 gene, VKORC1) have an important influence on warfarin therapy, particularly during initiation; however, there is a lack of consensus regarding the optimal pharmacogenetics-based initiation strategy. We conducted a prospective cohort study in which patients requiring warfarin therapy for atrial fibrillation or venous thromboembolism were initiated with a novel pharmacogenetics-initiation protocol (WRAPID, Warfarin Regimen using A Pharmacogenetics-guided Initiation Dosing) that incorporated loading and maintenance doses based on genetics, clinical variables, and response (n = 167, followed up for 90 days), to assess the influence of genetic variations on anticoagulation responses. Application of the WRAPID algorithm resulted in a negligible influence of genetic variation in VKORC1 or CYP2C9 on time to achievement of first therapeutic response (P = .52, P = .28) and risk of overanticoagulation (P = .64, P = .96). After adjustment for covariates, time to stable anticoagulation was not influenced by VKORC1 or CYP2C9 genotype. Importantly, time spent within or above the therapeutic range did not differ among VKORC1 and CYP2C9 genotype groups. Moreover, the overall time course of the anticoagulation response among the genotype groups was similar and predictable. We demonstrate the clinical utility of genetics-guided warfarin initiation with the WRAPID protocol to provide safe and optimal anticoagulation therapy for patients with atrial fibrillation or venous thromboembolism.

Clarifying the importance of CYP2C19 and PON1 in the mechanism of clopidogrel bioactivation and in vivo antiplatelet response.

AIMS: It is thought that clopidogrel bioactivation and antiplatelet response are related to cytochrome P450 2C19 (CYP2C19). However, a recent study challenged this notion by proposing CYP2C19 as wholly irrelevant, while identifying paraoxonase-1 (PON1) and its Q192R polymorphism as the major driver of clopidogrel bioactivation and efficacy. The aim of this study was to systematically elucidate the mechanism and relative contribution of PON1 in comparison to CYP2C19 to clopidogrel bioactivation and antiplatelet response. METHODS AND RESULTS: First, the influence of CYP2C19 and PON1 polymorphisms and plasma paraoxonase activity on clopidogrel active metabolite (H4) levels and antiplatelet response was assessed in a cohort of healthy subjects (n = 21) after administration of a single 75 mg dose of clopidogrel. There was a remarkably good correlation between H4 AUC (0-8 h) and antiplatelet response (r2 = 0.78). Furthermore, CYP2C19 but not PON1 genotype was predictive of H4 levels and antiplatelet response. There was no correlation between plasma paraoxonase activity and H4 levels. Secondly, metabolic profiling of clopidogrel in vitro confirmed the role of CYP2C19 in bioactivating clopidogrel to H4. However, heterologous expression of PON1 in cell-based systems revealed that PON1 cannot generate H4, but mediates the formation of another thiol metabolite, termed Endo. Importantly, Endo plasma levels in humans are nearly 20-fold lower than H4 and was not associated with any antiplatelet response. CONCLUSION: Our results demonstrate that PON1 does not mediate clopidogrel active metabolite formation or antiplatelet action, while CYP2C19 activity and genotype remains a predictor of clopidogrel pharmacokinetics and antiplatelet response.

Comparative effectiveness of salvage chemotherapy regimens and chimeric antigen T-cell receptor therapies in relapsed and refractory diffuse large B cell lymphoma: a network meta-analysis of clinical trials.

The optimal salvage chemotherapy regimen (SC) for relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) prior to autologous stem cell transplant remains unclear. Moreover, although chimeric antigen receptor T cell (CAR-T) therapies were recently approved for primary refractory DLBCL, head-to-head comparisons are lacking. We searched MEDLINE, EMBASE and CENTRAL to July 2022, for randomized trials that enrolled adult patients with R/R DLBCL and performed network meta-analyses (NMA) to assess the efficacy of SC and CAR-T therapies. NMA of SC (6 trials, 7 regimens, n = 1831) indicated that rituximab with gemcitabine, dexamethasone, cisplatin (R-GDP) improved OS and PFS over compared regimens. NMA of 3 CAR-T trials (n = 865) indicated that both axi-cel and liso-cel improved PFS over standard of care, with no difference in OS. Our results indicate that R-GDP may be preferred for R/R DLBCL over other SC compared. Longer follow-up is required for ongoing comparative survival analysis as data from CAR-T trials matures.

Factors associated with timely COVID-19 vaccination in a population-based cohort of patients with cancer.

BACKGROUND: In many jurisdictions, cancer patients were prioritized for COVID-19 vaccination because of increased risk of infection and death. To understand sociodemographic disparities that affected timely receipt of COVID-19 vaccination among cancer patients, we undertook a population-based study in Ontario, Canada. METHODS: Patients older than 18 years and diagnosed with cancer January 2010 to September 2020 were identified using administrative data; vaccination administration was captured between approval (December 2020) up to February 2022. Factors associated with time to vaccination were evaluated using multivariable Cox proportional hazards regression. RESULTS: The cohort consisted of 356 535 patients, the majority of whom had solid tumor cancers (85.9%) and were not on active treatment (74.1%); 86.8% had received at least 2 doses. The rate of vaccination was 25% lower in recent (hazard ratio [HR] = 0.74, 95% confidence interval [CI] = 0.72 to 0.76) and nonrecent immigrants (HR = 0.80, 95% CI = 0.79 to 0.81). A greater proportion of unvaccinated patients were from neighborhoods with a high concentration of new immigrants or self-reported members of racialized groups (26.0% vs 21.3%, standardized difference = 0.111, P < .001), residential instability (27.1% vs 23.0%, standardized difference = 0.094, P < .001), or material deprivation (22.1% vs 16.8%, standardized difference = 0.134, P < .001) and low socioeconomic status (20.9% vs 16.0%, standardized difference = 0.041, P < .001). The rate of vaccination was 20% lower in patients from neighborhoods with the lowest socioeconomic status (HR = 0.82, 95% CI = 0.81 to 0.84) and highest material deprivation (HR = 0.80, 95% CI = 0.78 to 0.81) relative to those in more advantaged neighborhoods. CONCLUSIONS: Despite funding of vaccines and prioritization of high-risk populations, marginalized patients were less likely to be vaccinated. Differences are likely due to the interplay between systemic barriers to access and cultural or social influences affecting uptake.

Association of COVID-19 Vaccination With Breakthrough Infections and Complications in Patients With Cancer.

Importance: Patients with cancer are known to have increased risk of COVID-19 complications, including death. Objective: To determine the association of COVID-19 vaccination with breakthrough infections and complications in patients with cancer compared to noncancer controls. Design, Setting, and Participants: Retrospective population-based cohort study using linked administrative databases in Ontario, Canada, in residents 18 years and older who received COVID-19 vaccination. Three matched groups were identified (based on age, sex, type of vaccine, date of vaccine): 1:4 match for patients with hematologic and solid cancer to noncancer controls (hematologic and solid cancers separately analyzed), 1:1 match between patients with hematologic and patients with solid cancer. Exposures: Cancer diagnosis. Main Outcomes and Measures: Outcomes occurring 14 days after receipt of second COVID-19 vaccination dose: primary outcome was SARS-CoV-2 breakthrough infection; secondary outcomes were emergency department visit, hospitalization, and death within 4 weeks of SARS-CoV-2 infection (end of follow-up March 31, 2022). Multivariable cumulative incidence function models were used to obtain adjusted hazard ratio (aHR) and 95% CIs. Results: A total of 289 400 vaccinated patients with cancer (39 880 hematologic; 249 520 solid) with 1 157 600 matched noncancer controls were identified; the cohort was 65.4% female, and mean (SD) age was 66 (14.0) years. SARS-CoV-2 breakthrough infection was higher in patients with hematologic cancer (aHR, 1.33; 95% CI, 1.20-1.46; P < .001) but not in patients with solid cancer (aHR, 1.00; 95% CI, 0.96-1.05; P = .87). COVID-19 severe outcomes (composite of hospitalization and death) were significantly higher in patients with cancer compared to patients without cancer (aHR, 1.52; 95% CI, 1.42-1.63; P < .001). Risk of severe outcomes was higher among patients with hematologic cancer (aHR, 2.51; 95% CI, 2.21-2.85; P < .001) than patients with solid cancer (aHR, 1.43; 95% CI, 1.24-1.64; P < .001). Patients receiving active treatment had a further heightened risk for COVID-19 severe outcomes, particularly those who received anti-CD20 therapy. Third vaccination dose was associated with lower infection and COVID-19 complications, except for patients receiving anti-CD20 therapy. Conclusions and Relevance: In this large population-based cohort study, patients with cancer had greater risk of SARS-CoV-2 infection and worse outcomes than patients without cancer, and the risk was highest for patients with hematologic cancer and any patients with cancer receiving active treatment. Triple vaccination was associated with lower risk of poor outcomes.

Mortality among patients with diffuse large B-cell lymphoma and mental disorders: a population-based study.

BACKGROUND: Mental disorders have been reported in patients with diffuse large B-cell lymphoma (DLBCL), but studies examining their association with mortality are lacking. METHODS: We conducted a population-based study using linked administrative health-care databases from Ontario, Canada. All patients with DLBCL 18 years of age or older treated with rituximab-based therapy between January 1, 2005, and December 31, 2017, were identified and followed until March 1, 2020. Mental disorders were defined as either preexisting or postdiagnosis (after lymphoma treatment initiation). Cox proportional hazards models were used to estimate the adjusted hazard ratio (HR) between mental disorders and 1-year and all-cause mortality while controlling for covariates. RESULTS: We identified 10 299 patients with DLBCL. The median age of the cohort was 67 years; 46% of patients were female, and 28% had a preexisting mental disorder. At 1-year follow-up, 892 (9%) had a postdiagnosis mental disorder, and a total of 2008 (20%) patients died. Preexisting mental disorders were not associated with 1-year mortality (adjusted HR = 1.06, 95% confidence interval [CI] = 0.96 to 1.17, P = .25), but postdiagnosis disorders were (adjusted HR = 1.51, 95% CI = 1.26 to 1.82, P = .0001). During a median follow-up of 5.2 years, 2111 (22%) patients had a postdiagnosis mental disorder, and 4084 (40%) patients died. Both preexisting and postdiagnosis mental disorders were associated with worse all-cause mortality (preexisting adjusted HR = 1.12, 95% CI = 1.04 to 1.20, P = .0024; postdiagnosis adjusted HR = 1.63, 95% CI = 1.49 to 1.79, P < .0001). CONCLUSIONS: Patients with DLBCL and mental disorders had worse short-term and long-term mortality, particularly those with postdiagnosis mental disorders. Further studies are needed to examine mental health service utilization and factors mediating the relationship between mental disorders and inferior mortality.