Exact Sciences’ cancer blood test achieves 51% sensitivity in prospective trial

Dive Brief:

Exact Sciences’ multi-cancer early detection (MCED) blood test has achieved 50.9% sensitivity at 98.5% specificity across 21 cancer types, the company said Monday at the American Association for Cancer Research’s annual meeting in San Diego.
Sensitivity rose to 63.7% in the six cancer types with the shortest five-year survival rate, including lung, ovary and pancreas. Leerink Partners analysts said the results “appear promising” in a note to investors, adding that the test could be more cost-effective than sequencing-based products such as Grail’s Galleri.
A registrational clinical trial could be the next step but Exact has scaled back investment in MCED because Congress is yet to pass legislation to explicitly give Medicare authority to pay for such tests.

Dive Insight:

Exact previously used retrospectively collected samples to train and assess up to four different biomarker classes for the detection of cancers in a case-control study, the company said in its presentation poster. The new data cover two of the biomarkers, methylation and protein, in samples from a multi-center, prospective study.

Exact’s test stands apart from other MCED diagnostics because of its focus on methylation and protein biomarkers that capture shared, cancer-associated signals but are released into the blood via different mechanisms. By eliminating the need to perform next-generation sequencing, Exact’s test could be more cost-effective than rival products, Leerink analysts said.

The company used more than 3,000 samples to train the test and then almost 3,200 additional samples to test its performance. The overall sensitivity of 50.9% rose when the analysis was limited to certain cancers. Sensitivity hit 54.8% when the analysis was limited to cancers without standard-of-care screening for average-risk populations. Excluding only breast and prostate cancer bumped sensitivity up to 56.8%.

The researchers saw the highest sensitivity, 63.7%, in six cancers with the shortest five-year survival rate, tumors of the pancreas, esophagus, liver, lung and bronchus, stomach and ovary. Sensitivity correlated to cancer stage in all the analyses, climbing from 15.4% for Stage 1 to 85.5% for Stage 4 in the overall dataset. Leerink cited the Stage 1 data as evidence that MCED “remains a higher technical obstacle vs [colorectal cancer] screening.”

Exact reported 61% sensitivity and 98.2% specificity for an MCED test that looked at four biomarkers, methylation, protein, aneuploidy and gene mutations, in 2022. Back then, the company planned to start a registrational study in 2023. Exact CEO Kevin Conroy said why the trial is yet to start on an earnings call in February.

“We have been saying for probably the prior 18 months [that] if Congress did not move to pass legislation to explicitly give Medicare the authority to pay for a multi-cancer early detection test, we would likely scale back our investment,” Conroy said. “We have scaled back our investment in MCED.”