Abstract P5-02-02: The final study report on the performance of Klarify™. Assessment of full data set from NCT01839045 a 6-month liquid biopsy panel run in women under the age of 50 that were initially assessed as a high risk population
Authors: Reese DE , Lourenco A , Mulpuri R , Borman S , Benson K , Alpers J , Silver M 
Published: May 2016

The precise diagnosis of breast lesions represents a significant problem in women under the age of 50, especially given the high prevalence of confounding factors such as dense breast. No new approaches have been developed to augment standard of care in the more precise detection of breast cancer. The combination of breast imaging with a robust protein signature that would detect biochemical cues of breast cancer offers a potentially attractive approach to detection regardless of the quality of the radiographic evidence. We have recently tested a protein signature (KARIFY BREAST™) composed of immune-regulatory cytokines, growth factors and tumor-associated autoantibodies (TAAbs). Here, we confirm the hypothesis that this protein signature, combined with standard of care can increase the precision of the diagnosis of breast cancer in women under the age of 50. We have tested this method in a prospective study of 351 women at 8 centers across the US in a randomized and blinded manner. Presented is both data from the initial blood draw and results of the six-month follow up blood draw. The achievement of 93% sensitivity and greater than a 80 percent specificity was demonstrated.

Methods: Provista-001 enrolled 351 patients from 9 sites across the US and will follow patients for 6 months prior to first blood draw under IRB approval. Upon enrollment, patients were randomized to either training or validation groups. Clinical truth was set at equal to or greater than 80% sensitivity/specificity. Serum protein biomarkers and autoantibodies identified in prior proteomic screens were measured prior to biopsy. Individual biomarker (25 serum protein biomarkers (SPB) and TAAbs) concentrations were measured , together with specific patient data were evaluated using various logistic regression models. Additionally, 200 patients were used as a training set to develop and refine new models, which were then validated in the remaining 151 subjects. Clinical findings were compared to biopsy (largely BIRADS 4) or were followed for 6 months and re-assessed (BIRADS 3).

The novel algorithm utilizing patient data, SPBs and TAAb concentrations and regression models were able to distinguish benign from breast cancer lesions in a statistically significant manner. Importantly, the SPBs alone were unable to adequately distinguish benign lesions, consistent with prior work. However, the addition of TAAbs markedly increased both the sensitivity (93%) and specificity (80.3%) of the assay in this group of women. The use of the algorithm in conjunction with imaging detected more lesions than imaging alone.

Our findings suggest that when used in combination, the protein signature developed here and breast imaging provides a more precise detection methodology than either alone. This is particularly important in women under the age of 50 where detection is difficult. The follow-up data at six months (BIRADS 3) have yielded additional data in this understudied group of women. Such as the apparent lack of effect of breast density on early detection when using the algorithm.

Citation Format: Reese DE, Lourenco A, Mulpuri R, Borman S, Benson K, Alpers J, Silver M. The final study report on the performance of Klarify™. Assessment of full data set from NCT01839045 a 6-month liquid biopsy panel run in women under the age of 50 that were initially assessed as a high risk population. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-02-02.