Treatment Patterns and Efficacy of Chemotherapy After Pembrolizumab in Advanced Urothelial Cancer-a Real-World Study in the pre-Antibody-Drug Conjugate Era

BACKGROUND

Immune checkpoint inhibitors (ICIs) have been established as a routine treatment in patients with metastatic urothelial cancer (mUC). However, there has been no standard of care after progression on ICIs. We investigated real-world treatment patterns and efficacy of chemotherapy (CHT) after pembrolizumab, in the era before introduction of maintenance avelumab and antibody-drug conjugates (ADC).

PATIENTS AND METHODS

An observational, retrospective study was conducted at twelve Nordic centers. Patients with mUC were treated according to investigator´s choice of CHT after pembrolizumab. Primary endpoint was overall response (ORR) and disease control rate (DCR); secondary endpoints were progression-free (PFS) and overall survival (OS).

RESULTS

In total, 102 patients were included whereof 23 patients received CHT after pembrolizumab as second line treatment (subcohort A) and 79 patients in third line (subcohort B). Platinum-gemcitabine combinations were the most common regimens in subcohort A, and vinflunine in subcohort B. The ORR and DCR were 36% and 47%, respectively. Presence of liver metastases was independently associated with lower ORR and DCR. The PFS and OS were 3.3 months and 7.7 months, respectively. Eastern Cooperative Oncology Group Performance Status (ECOG PS) and number of previous cycles of pembrolizumab were found to be independent prognostic factors associated with OS.

CONCLUSION

In a real-world setting, CHT showed clinically meaningful response rates and survival in mUC patients after progression with pembrolizumab. Clinical benefit may primarily be achieved in patients with favorable ECOG PS, in patients treated with > 6 cycles pembrolizumab as well as in patients without presence of liver metastases.

Selenium concentration and cardiovascular disease risk: Mendelian randomization study

Background/Introduction

Selenium has been associated with cardiovascular disease (CVD) risk in observational studies; however, the causality of the association remains unestablished.

Purpose

To examine the associations of selenium concentrations with 15 CVDs using Mendelian randomization analysis.

Methods

Genetic variants significantly associated with concentrations of toenail and blood (TAB) and blood selenium in mild linkage disequilibrium (r2 <0.3) were used as instrumental variables. Summary-level data for 15 CVDs were obtained from the UK Biobank study (n=367,561), FinnGen study (n=218,792), and six international consortia. The inverse variance weighted method accounting for linkage disequilibrium was used to estimate the associations. Results for one outcome from different sources were combined using the fixed effect meta-analysis method. Bonferroni correction was used to account for multiple testing, and associations with P value ≤0.003 (0.05 / 15 outcomes) were described as significant. Associations with P value between ≤0.05 and >0.003 were regarded as suggestive associations.

Results

Genetically predicted concentrations of TAB selenium were not significantly associated with the risk of the 15 CVDs. However, there were suggestive associations of genetically predicted higher concentrations of TAB selenium with increased risk of atrial fibrillation and peripheral artery disease. The odds ratio per one-unit increase in log-transformed concentrations of TAB selenium was 1.07 (95% confidence interval, 1.01–1.12; P=0.019) for atrial fibrillation and 1.20 (95% confidence interval, 1.05–1.38; P=0.008) for peripheral artery disease. We observed no associations between genetically predicted blood selenium concentrations and risk of the 15 CVDs.

Conclusions

Genetically predicted higher concentrations of TAB or blood selenium were not associated with a lower risk of CVD, which suggests that high selenium status may not prevent CVD development. The suggestive positive associations of TAB selenium with atrial fibrillation and peripheral artery disease warrants verification.

Funding Acknowledgement

Type of funding sources: None.

AB0318 RISK FOR CONCOMITANT AUTOIMMUNITY IN PATIENTS WITH ANTIPHOSPHOLIPID SYNDROME; A SWEDISH COHORT STUDY

Background:

In patients with the antiphospholipid syndrome (APS), concomitant systemic autoimmune rheumatic diseases (SARD) are common and often associated with more disease associated damage.

Less is known about the prevalence of non-rheumatic autoimmune diseases (NRAID) in patients with APS.

Objectives:

To evaluate the incidence and prevalence of concomitant autoimmune diseases (AID) in a cohort of APS patients. The risk of AID was also evaluated with respect to the antiphospholipid antibodies (aPL) profiles.

Methods:

This retrospective cohort study comprises consecutive patients identified with APS through review of electronic medical records at Karolinska University Hospital, Sweden between 2014 and 2020. Exclusion criteria were misdiagnosis and age <18. Descriptive statistics was used for baseline data and multivariable Cox proportional hazard regression analysis to investigate the risk factors to develop new onset AID. Ethical approval was obtained from the Swedish Ethical Review Authority (2020-02333).

Results:

Of 271 included patients, 66% were women and the median age at diagnosis of APS was 43 years (IQR 31–55). At inclusion, 130 (48%) patients presented with other AID; 101 (37%) of them had a concomitant SARD while 54 (19%) had a NRAID. Systemic lupus erythematosus (SLE) was the most frequent in 30% of patients, followed by autoimmune thyroid disease (ATD) in 10% of patients.

In addition, 35 (13%) APS-patients developed AID during the study period, corresponding to an incidence rate of 28.4 (95% CI; 19.3-40.3) per 1.000 person-years with mean time at risk of 4 (±2) years. Twenty-one (8%) patients developed a SARD and further 14 (5%) were diagnosed with a NRAID.

The cumulative incidence for AID was significantly higher in patients with high titers of IgG aPL. Patients that developed SARD had significantly higher median titers of a-β2GPI IgG isotype, p=0.05. In the NRAID group, median a-β2GPI and aCL IgG isotypes were significantly increased, p=0.02 and p=0.04, respectively. The hazard ratio to develop diagnosis of AID was significantly increased in patients with high titers of the IgG isotype aPL (HR 2.4 95% CI; 1.1-5.3). Obstetric APS manifestations were associated with a significantly increased hazard ratio of 2.8 (95% CI; 1.1-7.7) to develop SARD, and also trendwise for AID, as a compound variable.

During the study period, 52 patients had at least one new APS manifestation, as defined by the Sydney criteria (1). In comparison to patients without new manifestations, these patients had significantly higher median titers of aPL of the IgG isotype, and concomitant AID at first visit (p=0.01, p=0.02, respectively).

Conclusion:

APS patients are at high risk to develop other AID, and APS patients with concomitant AID had an increased risk to develop new clinical APS manifestations. These findings might be helpful when considering risk stratification and alternate treatment options in this patient group.

References:

[1]Miyakis S, Lockshin MD, Atsumi T et al. International consensus statement on an update of the classification criteria for definite antiphospholipid syndrome (APS). J Thromb Haemost 2006; 4: 295–306.

Acknowledgements:

I have no acknowledgements to declare.

Disclosure of Interests:

None declared

Predicting venous thrombosis in women using a combination of genetic markers and clinical risk factors

BACKGROUND

Family history of venous thromboembolism (VTE) has been suggested to be more useful in risk assessment than thrombophilia testing.

OBJECTIVES

We investigated established genetic susceptibility variants for association with VTE and evaluated a genetic risk score in isolation and combined with known trigger factors, including family history of VTE.

PATIENTS/METHOD

A total of 18 single nucleotide polymorphisms (SNPs) selected from the literature were genotyped in 2835 women participating in a Swedish nationwide case-control study (the ThromboEmbolism Hormone Study [TEHS]). Association with VTE was assessed by odds ratios (ORs) with 95% confidence interval (CI) using logistic regression. Clinical and genetic predictors that contributed significantly to the fit of the logistic regression model were included in the prediction models. SNP-SNP interactions were investigated and incorporated into the models if found significant. Risk scores were evaluated by calculating the area under the receiver-operating characteristics curve (AUC).

RESULTS

Seven SNPs (F5 rs6025, F2 rs1799963, ABO rs514659, FGG rs2066865, F11 rs2289252, PROC rs1799810 and KNG1 rs710446) with four SNP-SNP interactions contributed to the genetic risk score for VTE, with an AUC of 0.66 (95% CI, 0.64-0.68). After adding clinical risk factors, which included family history of VTE, the AUC reached 0.84 (95% CI, 0.82-0.85). The goodness of fit of the genetic and combined scores improved when significant SNP-SNP interaction terms were included.

CONCLUSION

Prediction of VTE in high-risk individuals was more accurate when a combination of clinical and genetic predictors with SNP-SNP interactions was included in a risk score.

Studies of microparticles in patients with the antiphospholipid syndrome (APS)

OBJECTIVES

To study circulating platelet, monocyte and endothelial microparticles (PMPs, MMPs and EMPs) in patients with antiphospholipid syndrome (APS) in comparison with healthy controls.

MATERIAL AND METHOD

Fifty-two patients with APS and 52 healthy controls were investigated. MPs were measured on a flow cytometer (Beckman Gallios) and defined as particles sized < 1.0 µm, negative to phalloidin, positive to lactadherin and positive to either CD42a (PMPs), CD144 (EMPs) or CD14 (MMPs). Exposure of CD142 (TF) was measured on CD144 positive MPs.

RESULTS

Total number of MPs (i.e. lactadherin positive particles) was higher in APS patients versus controls (p < 0.001). An increased number of EMPs (p < 0.001), increased TF-positive EMPs (p < 0.001) and increased MMPs (p < 0.001) were also observed. PMP numbers did not differ between the groups. None of the MP types differed in numbers between obstetric and thrombotic APS patients.

CONCLUSION

We observed a high number of EMPs expressing TF in APS patients. The numbers of MMPs and total EMPs were also higher as compared with healthy controls but in contrast to previous reports, the number of PMPs did not differ between groups.

[Celiac disease can be associated with severe neurological symptoms. Analysis of gliadin antibodies should be considered in suspected cases]

Celiac disease can be associated with a wide spectrum of neurological and psychiatric symptoms (cerebellar ataxia, neuromuscular manifestations, epilepsy, dementia), even in the absence of malabsorption or gastrointestinal symptoms. The case of a 72-year-old man with a rapidly progressive, lethal encephalopathy secondary to celiac disease is reported, together with a review of documented neurological symptoms in celiac disease. The aetiology of these neurological symptoms is unknown, although immunological mechanisms are suspected.

T-cell recognition of lipid peroxidation products breaks tolerance to self proteins

Peroxidation of polyunsaturated fatty acids in lipoproteins and cell membrane phospholipids occurs in many situations in the body, both under normal and pathological conditions. Low-density lipoprotein is particularly prone to oxidation and is believed to be a pathogenetic component in atherogenesis. Both antibody responses and T-cell responses to oxidatively modified lipoproteins have been demonstrated in humans as well as in animal models. However, little is known about how these responses arise or how T cells recognize these antigens. In the present study, mice were immunized with homologous albumin covalently modified with a series of defined aldehydes which are known to be generated during lipid peroxidation. T-cell hybridomas from immunized animals demonstrated major histocompatibility complex-restricted and protein sequence-dependent responses to modified albumin, but not to native albumin. In addition to the response to modified epitopes, some aldehyde modifications resulted in strong antibody responses also to the non-modified protein. This T-cell-dependent break of tolerance constitutes a novel pathway for induction of autoimmunity by lipid peroxidation. The findings have implications in many situations where lipid peroxidation products are generated, including atherosclerosis and inflammatory and infectious diseases.

Expression of the macrophage scavenger receptor in atheroma. Relationship to immune activation and the T-cell cytokine interferon-gamma

Scavenger receptors mediate internalization of modified lipoproteins and foam cell transformation of monocyte-derived cytokines. We investigated macrophage scavenger receptor (MSR) expression in monocyte-macrophages from human peripheral blood and in atherosclerotic lesions and analyzed its relationship to T lymphocytes and immunoregulatory cytokines by immunohistochemistry and polymerase chain reaction (PCR). Antibodies specific for the two MSR isoforms were generated by immunizing rabbits with isoform-specific synthetic peptides conjugated to keyhole limpet hemocyanin. In human atherosclerotic plaques, these antibodies stained macrophages and foam cells in a pattern that corresponded to the distribution of the macrophage marker CD68. CD3-positive T cells and alpha-actin-positive smooth muscle cells exhibited no reactivity to the anti-MSR antibodies. The frequency of cells stained with antibodies to MSR type I was equal to that of cells stained for type II, suggesting that most macrophages coexpress both isoforms. Reverse transcription (RT)-PCR analysis confirmed that both MSR isoforms were expressed in all plaques examined. There was, however, a tendency toward a lower immunohistochemical staining intensity for MSR type I and a decreased number of lipid-rich foam cells in T cell-rich areas. The mRNAs for interleukin-2 and interferon-gamma, two major products of activated T cells, were detected by RT-PCR in all plaques tested. This indicates that activation of T lymphocytes occurs in atherosclerotic plaques. Since interferon-gamma downregulates MSR expression, these observations suggest a potential mechanism for local regulation of MSR expression in the atherosclerotic plaque.