Clinical Validation of the Onclarity Assay After Assay Migration to the High-Throughput COR Instrument Using SurePath Screening Samples From the Danish Cervical Cancer Screening Program

Performance of BD Onclarity HPV assay on FLOQSwabs vaginal self-samples

This study assessed the accuracy of high-risk human papillomavirus testing of BD Onclarity HPV (Onclarity) assay on vaginal self-collected FLOQSwab versus cervical samples to ensure similar accuracy to detect cervical intraepithelial neoplasia. Testing was performed on two automated platforms, BD Viper LT and BD COR, to evaluate the effect of machine and using two vaginal self-samples to analyze the influence of collection, transport, and freezing-unfreezing on the results. A cervical sample and two self-samples were collected from 300 women. The first collected vaginal and the cervical sample were tested on BD Viper LT, and the second swab was frozen and subsequently tested on both automated systems. Test results on vaginal and cervical specimens were considered the index and comparator, respectively; colposcopy and histology were reference standards. Relative sensitivity for ≥CIN2 on vaginal samples analyzed versus the cervical sample was 1.01 (0.97-1.06), 1.01 (0.97-1.06), and 1.00 (0.95-1.05), for the first, second self-collected sample tested on BD VIPER LT, and second self-collected sample tested on BD COR, respectively. Relative specificity was 0.83 (0.73-0.94), 0.76 (0.67-0.87), and 0.82 (0.73-0.92) using the three different workflows. Cut-off optimization for human papillomavirus (HPV) positivity defined at Ct ≤38.3 for HPV16, ≤ 34.2 for HPV18, and ≤31.5 for all other types showed an increased relative specificity with similar sensitivity. No significant difference was observed between self-samples tested with the two platforms and between first- and second-collected swabs. Onclarity assay on FLOQSwab using both platforms showed similar sensitivity but lower specificity to detect ≥CIN2 compared to cervical samples. By cut-off optimization, non-inferior specificity could be reached.

IMPORTANCE

Human papillomavirus (HPV) testing on self-collected vaginal samples has been shown to improve women's participation to cervical cancer screening programs, particularly in regions with limited access to health care. Nevertheless, the introduction of self-sampling in cervical cancer screening programs requires prior clinical validation of the HPV assay in combination with a self-sample collection device, including also the laboratory workflow and automation required for high-throughput testing in screening. In this study, the performance of BD Onclarity HPV on FLOQSwab-collected vaginal self-samples has been compared to clinician-taken liquid-based cytology samples, to detect high-grade cervical intraepithelial neoplasia using two high-throughput platforms, BD Viper LT and BD COR. The study findings have shown a similar performance of BD Onclarity on testing self-collected samples, confirming the validation of the proposed pre-analytical and analytical protocols for their use in cervical cancer screening programs based on self-collected vaginal samples.

Cost-Effectiveness Analysis of HPV Extended versus Partial Genotyping for Cervical Cancer Screening in Singapore

Human papillomavirus (HPV) partial genotyping (PGT) identifies HPV16 and HPV18 individually, alongside 12 other high-risk HPV genotypes (hrHPV) collectively. HPV extended genotyping (XGT) identifies four additional hrHPV individually (HPV31, 45, 51, and 52), and reports the remaining eight in three groups (HPV33|58; 56|59|66; 35|39|68). Quality-adjusted life years (QALY), health care resource use, and costs of XGT were compared to PGT for cervical cancer screening in Singapore using DICE simulation. Women with one of the three hrHPV identified by XGT (HPV35|39|68; 56|59|66; 51), and atypical squamous cells of undetermined significance (ASCUS) on cytology, are recalled for a repeat screening in one year, instead of undergoing an immediate colposcopy with PGT. At the repeat screening, the colposcopy is performed only for persistent same-genotype infections in XGT, while with PGT, all the women with persistent HPV have a colposcopy. Screening 500,122 women, aged 30-69, with XGT, provided an incremental cost-effectiveness ratio (ICER) versus PGT of SGD 16,370/QALY, with 7130 (19.4%) fewer colposcopies, 6027 (7.0%) fewer cytology tests, 9787 (1.6%) fewer clinic consultations, yet 2446 (0.5%) more HPV tests. The XGT ICER remains well below SGD 100,000 in sensitivity analyses, (-SGD 17,736/QALY to SGD 50,474/QALY). XGT is cost-effective compared to PGT, utilizes fewer resources, and provides a risk-based approach as the primary cervical cancer screening method.

Validation of a New High-Throughput BD COR System Using the BD CTGCTV2 Assay

This study determined the precision and reproducibility of results for the BD CTGCTV2 (CTGCTV2) assay on the BD COR System (COR). The clinical performance of the CTGCTV2 assay conducted on COR was compared with its performance on the BD MAX System (MAX) for detecting Chlamydia trachomatis, Neisseria gonorrhoeae, or Trichomonas vaginalis. The multiday precision and multisite reproducibility studies were conducted using contrived panels of positive and negative urine and PreservCyt specimens. A total of 433 panel members, generated from remnant clinical specimens, were tested in the clinical comparison study. Each panel member was tested three times on MAX and three times on COR. The results in the same testing group were compared for agreement by target. The cycle threshold scores from MAX and COR were analyzed by paired t-test and Deming regression. The CTGCTV2 assay on COR showed high reproducibility in the multiday and multisite precision analysis. The point estimates of positive percent agreement and negative percent agreement in the clinical comparison study for all three targets were greater than 95%, with all corresponding lower bounds of two-sided 95% CIs greater than 90%. Cycle threshold score comparison showed no systematic difference between the two systems. The results of this study show equivalent performance of the CTGCTV2 assay on the MAX and COR systems.