Oncology clinical trial disruption during the COVID-19 pandemic: a COVID-19 and cancer outcomes study

Background

COVID-19 disproportionately impacted patients with cancer as a result of direct infection, and delays in diagnosis and therapy. Oncological clinical trials are resource-intensive endeavors that could be particularly susceptible to disruption by the pandemic, but few studies have evaluated the impact of the pandemic on clinical trial conduct.

Patients and methods

This prospective, multicenter study assesses the impact of the pandemic on therapeutic clinical trials at two large academic centers in the Northeastern United States between December 2019 and June 2021. The primary objective was to assess the enrollment on, accrual to, and activation of oncology therapeutic clinical trials during the pandemic using an institution-wide cohort of (i) new patient accruals to oncological trials, (ii) a manually curated cohort of patients with cancer, and (ii) a dataset of new trial activations.

Results

The institution-wide cohort included 4756 new patients enrolled to clinical trials from December 2019 to June 2021. A major decrease in the numbers of new patient accruals (−46%) was seen early in the pandemic, followed by a progressive recovery and return to higher-than-normal levels (+2.6%). A similar pattern (from −23.6% to +30.4%) was observed among 467 newly activated trials from June 2019 to June 2021. A more pronounced decline in new accruals was seen among academically sponsored trials (versus industry sponsored trials) (P < 0.05). In the manually curated cohort, which included 2361 patients with cancer, non-white patients tended to be more likely taken off trial in the early pandemic period (adjusted odds ratio: 2.60; 95% confidence interval 1.00-6.63), and substantial pandemic-related deviations were recorded.

Conclusions

Substantial disruptions in clinical trial activities were observed early during the pandemic, with a gradual recovery during ensuing time periods, both from an enrollment and an activation standpoint. The observed decline was more prominent among academically sponsored trials, and racial disparities were seen among people taken off trial.

Use of carbonic anhydrase IX (CAIX) expression and Von Hippel Lindau (VHL) gene mutation status to predict survival in renal cell carcinoma

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Background: VHL gene mutations induce the expression of CAIX, and previous studies have shown that low CAIX results in worse prognosis for RCC. We attempt to further describe the relationship between CAIX expression, VHL gene mutations and tumor characteristics. Methods: Radical nephrectomy was performed in 100 patients at 2 centers. Genomic DNA was extracted from frozen tumor samples using the QIAmp DNA mini kit. Four amplimers covering the whole coding sequence of the VHL gene were synthesized by PCR and sequenced by Big Dye. Mutation bearing sequences were confirmed by a second round of sequencing. The monoclonal antibody M75 was used to score the expression of the CAIX protein. Life table, Kaplan-Meier and Cox regression analyses addressed RCC-specific mortality (RCC-SM). Results: VHL mutations were identified in 58 patients (58%) and CAIX tumor expression ranged from 0% to 100%. Low CAIX expression (<85%) was associated with absence of VHL mutation (p=0.02), larger tumors (p=0.002), higher T stage (p=0.007), nodal metastases (p=0.001) and higher Fuhrman grade (p=0.006). Absence of VHL mutation was associated with worse ECOG (p=0.005), higher T stage (p=0.01) and presence of nodal (p=0.03) and distant metastases (p=0.02). Categorically-coded, CAIX was a statistically significant predictor of RCC-SM (p=0.002), while VHL mutation approached statistical significance (p=0.08) and a trend was observed for worse survival when VHL was not mutated. Patients with both high CAIX and VHL mutation had better survival (95.9% 1 year and 6 year median survival) than their counterparts with low CAIX expression and absence of VHL mutation (62.9% 1 year and 1.5 year median survival) (p<0.001). In Cox regression analyses, neither CAIX (p=0.06) nor VHL (p=0.4) achieved independent predictor status, when adjusted for age, gender, TNM stage, tumor size, Fuhrman and ECOG. Conclusions: Low CAIX expression is associated with the absence of VHL mutation and aggressive tumor characteristics, and is a statistically significant predictor of poor prognosis in patients with clear cell RCC.

No significant financial relationships to disclose.

Use of enhanced green fluorescent protein to optimize and quantitate infection of target cells with recombinant retroviruses

Recombinant retroviral vectors are useful tools for gene transfer in both gene therapy and research applications. An enhanced form of green fluorescent protein has been incorporated into recombinant retroviruses as a marker to follow infected cells. In this paper, we extended the use of the fluorescent reporter to quantify protein expression using such analytical tools as fluorescent microscopy, flow cytometry and fluorescent plate reader analysis. These tools enabled us to rapidly assess the titer of recombinant retrovirus harvested from packaging cells and to optimize parameters for infection of different cell lines.