Grail Inc., a startup with investors including Microsoft’s Bill Gates and Amazon’s Jeff Bezos, made a splash earlier this year when it unveiled plans to develop a blood-based screening test for cancer. The first clinical trial is now underway, the company announced on Dec. 1.

OHSU Knight Cancer Institute Director Brian Druker, M.D., who is a member of Grail’s scientific advisory board, said the study represents a “critically important” step in establishing the foundational knowledge that will be needed to advance early detection.

“Cancer is an incredibly complex and heterogeneous disease, making accurate, early stage detection extremely difficult,” Druker said in a statement to news outlets.

Grail’s approach is to use next-generation gene sequencing to glean information from fragments of tumor DNA and RNA, which can be found in blood. The company’s Circulating Cell-free Genome Atlas study will collect biological samples from at least 7,000 people with a new diagnosis of cancer and from at least 3,000 others who do not have a diagnosis of cancer. The aim is to develop models for distinguishing cancer from non-cancer.

The company – a spinout of gene-sequencing giant Illumina, Inc. – said in January that it secured over $100 million from Illumina and ARCH Venture Partners, with participating investors including Bezos Expeditions, Bill Gates, Sutter Hill Ventures, and GV (formerly Google Ventures). The company is attempting to raise $1.7 billion for clinical trials, Fast Company reported.

Here are more details from the study description on file at ClinicalTrials.gov:

Design: The prospective, multi-center, observational study will collect de-identified biospecimens and clinical data from participants at six U.S. clinical sites at least annually for up to five years.

Primary outcome measures: 1) Evidence of histologically confirmed cancer in subjects with circulating tumor DNA detected by deep sequencing. 2) Clinically annotated plasma samples from cancer and non-cancer subjects will undergo deep sequencing to characterize cell-free nucleic acid profiles and to estimate the population heterogeneity in the two arms of the study.

Secondary outcome measures: 1) Number of genomic variants detected in plasma cell free nucleic acids in cancer subjects who also have available tumor tissue. 2) Concordance of variants identified in sequencing plasma cell free nucleic acids and tumor tissue from the same subject will be evaluated. 3) Survival or clinical cancer status of all subjects with results from deep sequencing of plasma cell-free nucleic acids. 4) Explore the relationship between genomic results and clinical outcomes based on collection of longitudinal information (at least annually for up to 5 years) from medical records.

Biospecimen Retention: Samples with DNA, plasma, white blood cells, and formalin-fixed paraffin embedded tumor tissue.

Estimated enrollment: 10,000.

Estimated completion date: August 2022.

Clinical sites: Hartford HealthCare Cancer Institute in Hartford, Connecticut; Baptist Health in Lexington, Louisville and Paducah, Kentucky; Bon Secours Saint Francis Cancer Center in Greenville, South Carolina; Spartanburg Regional Healthcare System in Spartanburg, South Carolina.