MENLO PARK, Calif.–(BUSINESS WIRE)–GRAIL, Inc., a healthcare company focused on the early detection of cancer, today announced that new data from the Circulating Cell-free Genome Atlas (CCGA) Study will be presented during the 2018 American Society of Clinical Oncology (ASCO) Annual Meeting taking place June 1-5 in Chicago. Data will be highlighted in four abstracts, including two oral presentations.
Previously presented data from the first pre-planned sub-study of CCGA supported the possibility of developing a highly specific blood test for early detection of cancer with a very low rate of false positive results.1
New data from the same sub-study suggest a blood test can be developed to detect multiple types of cancer at early stages (Abstract 12021). Sensitivity analyses were conducted by sequencing blood samples from 878 participants with newly diagnosed cancer with three prototype genome sequencing assays. In general, results were comparable for the three prototype assays. Data for all three assays will be presented at the ASCO Annual Meeting. Results for the whole-genome bisulfite sequencing assay are reported in this press release. Detection rates (sensitivity at 98 percent specificity) ranged from 56 percent to 80 percent at early stages (stages I-III) in participants with cancer types that generally cause high mortality, including colorectal, esophageal, head and neck, liver, ovarian, pancreatic, and triple-negative breast cancers, as well as lymphoma and multiple myeloma.
Strong biological signal was also detected for lung cancer, the leading cause of cancer death globally, and these data will be highlighted in a late-breaking abstract that will be featured in ASCO’s press program on Saturday, June 2, 2018 (Abstract LBA8501).
Cancer types that exhibited low signal at early stages (less than 10 percent sensitivity), included prostate, thyroid, uterine, and renal cancers, and melanoma.
“Our initial CCGA results support the continued development of a highly specific blood test that can detect multiple cancer types early, when tumors can still be removed by surgery and treatment may be more successful,” said Anne-Renee Hartman, MD, Vice President of Clinical Development. “These data are especially encouraging, as we were able to detect strong, blood-based biological signal at early stages for cancers that are responsible for the majority of cancer deaths globally, most of which are not typically screened for.”
In this initial discovery phase of CCGA, three prototype genome sequencing assays were used to evaluate cancer-defining features in cell-free nucleic acids. The company is now verifying initial results from this CCGA sub-study in an independent data set from the same CCGA sub-study. The assays and GRAIL’s machine learning algorithms will then be optimized to determine the most informative genomic features for continued development and validation of a blood test for early detection of multiple cancer types in larger data sets in the CCGA and STRIVE studies.
Additional Results
Detection rates (sensitivity at 98 percent specificity) with the whole-genome bisulfite sequencing assay at stages I-III for cancer types with strong blood-based biological signal, are detailed in the table below. Detection rates for breast cancer subtypes at stages I-III are also detailed (Abstract 536).
The overall detection rate (sensitivity at 98 percent specificity) for breast cancer at stages I-III was 21 percent. Triple-negative breast cancer had strong biological signal at stages I-III (56 percent). Participants whose cancer was diagnosed through clinical presentation (diagnosis as a result of symptoms or through a different clinical setting than screening) had stronger signal than those diagnosed through screening mammography (sensitivity for stages I-IV breast cancer diagnosed through clinical presentation: 38 percent [95 percent confidence interval: 31 to 46 percent] vs. screen-detected breast cancer: 9 percent [95 percent confidence interval: 5 to 14 percent]).
Detection Rates (Sensitivity) for Cancers at Stages I-III at 98 Percent Specificity with Prototype Whole-Genome Bisulfite Sequencing Assay
| Cancer Type (N) | Detection Rate (95% Confidence Interval) |
| Ovarian (10) | 80% (44-98%) |
| Liver (5) | 80% (28->99%) |
| Lymphoma (16) | 69% (41-89%) |
| Multiple Myeloma (11) | 64% (31-89%) |
| Pancreatic (10) | 60% (26-88%) |
| Colorectal (27) | 63% (42-81%) |
| Esophageal (19) | 58% (34-80%) |
| Head and Neck (9) | 56% (21-86%) |
| Breast (333) | 21% (17-26%) |
| Triple-negative (48) | 56% (41-71%) |
| HER2-positive (56) | 34% (22-48%) |
| Hormone receptor-positive/ HER2-negative (217) | 11% (7-16%) |
Details for Presentations/Posters Featuring GRAIL’s Data
Abstract LBA8501
Genome-wide sequencing for early stage lung cancer detection from plasma cell-free DNA (cfDNA): The Circulating Cell-free Genome Atlas (CCGA) study
ASCO Press Program: Saturday, June 2, 2018: 8:00-9:00am CDT
Oral Presentation: Monday, June 4, 2018: 8:12-8:24am CDT, Hall B1
Abstract 536
Breast cancer cell-free DNA (cfDNA) profiles reflect underlying tumor biology: The Circulating Cell-free Genome Atlas (CCGA) study
Poster Session: Saturday, June 2, 2018: 8:00-11:30am CDT, Hall A, Poster Board #28
Abstract 12021
Development of a comprehensive cell-free DNA (cfDNA) assay for early detection of multiple tumor types: The Circulating Cell-free Genome Atlas (CCGA) study
Poster Session: Monday, June 4, 2018: 1:15-4:45pm CDT, Hall A, Poster Board #134
Poster Discussion: Monday, June 4, 2018: 4:45-6:00pm CDT, Room S406
Abstract 12003
Prevalence of clonal hematopoiesis of indeterminate potential (CHIP) measured by an ultra-sensitive sequencing assay: Exploratory analysis of the Circulating Cell-free Genome Atlas (CCGA) study
Oral Presentation: Tuesday, June 5, 2018: 9:00-9:12am CDT, Room S406
About the First CCGA Sub-Study
In this pre-planned sub-study of CCGA, three prototype genome sequencing assays were evaluated as potential methods for a blood-based test for early cancer detection. In the first training phase of the sub-study, blood samples from 878 participants with newly diagnosed cancer who had not yet received treatment and 580 participants without diagnosed cancer were sequenced with all three prototype assays. Twenty different cancer types across all stages were included in the sub-study.
The prototype sequencing assays included:
- Targeted sequencing of paired cell-free DNA (cfDNA) and white blood cells to detect somatic mutations such as single nucleotide variants and small insertions and/or deletions;
- Whole-genome sequencing of paired cfDNA and white blood cells to detect somatic copy number changes; and
- Whole-genome bisulfite sequencing of cfDNA to detect abnormal cfDNA methylation patterns.
About CCGA
CCGA is a prospective, observational, longitudinal study designed to characterize the landscape of cell-free nucleic acid (cfNA) profiles in people with and without cancer. The planned enrollment for the study is more than 15,000 participants across 141 sites in the United States and Canada. Approximately 70 percent of participants will have cancer at the time of enrollment (newly diagnosed, have not yet received treatment) and 30 percent will not have a known cancer diagnosis. The groups are demographically similar and representative of a real-world population. The group of participants without cancer includes individuals with conditions that are known to increase cfNA signal, such as inflammatory or autoimmune diseases. Planned follow-up for all participants is at least five years to collect clinical outcomes.
About STRIVE
STRIVE is a prospective, observational, longitudinal cohort study enrolling 120,000 women at the time of their screening mammogram. It is designed to evaluate blood tests for the early detection of multiple cancer types.
About GRAIL
GRAIL is a healthcare company whose mission is to detect cancer early, when it can be cured. GRAIL is using the power of high-intensity sequencing, population-scale clinical studies, and state-of-the-art computer science and data science to enhance the scientific understanding of cancer biology, and to develop and commercialize pioneering products for the early detection of cancer. The company is located in Menlo Park, California and Hong Kong. It is supported by leading global investors and pharmaceutical, technology, and healthcare companies. For more information, please visit www.grail.com.
1 GRAIL press release, April 17, 2018; http://www.abstractsonline.com/pp8/#!/4562/presentation/10970