NEW YORK – Chinese cancer genomic sequencing firm Burning Rock Biotech has begun recruiting participants for a case-control study designed to validate a 22-cancer early detection assay that combines epigenetic, protein, and potentially other molecular biomarkers.
Expected to enroll fully by 2023 and to read out its first results by the end of that year, the study, called PRESCIENT, or the Pan-Cancer Early-Stage Detection by Liquid Biopsy Technique Project, is being led by Jie He, a fellow of the Chinese Academy of Sciences and head of the China National Cancer Center.
Investigators will profile blood samples from a little under 12,000 individuals, split between patients with cancer and healthy controls, and will include a training and a validation set. The goal is to demonstrate sufficient performance for the company to continue to push the assay toward commercialization.
The study joins a slate of other research that Burning Rock has initiated as it has developed a set of increasingly broad cancer screening panels, all driven by the detection of blood-based epigenetic signals.
On a call this week to discuss the firm's quarterly financial results, Shannon Chuai, Burning Rock's chief operating officer, said that unlike some other companies pursuing early cancer detection, such as US firm Grail, Burning Rock's strategy has been to build out broader assays in a stepwise fashion while simultaneously validating their smaller predecessors for more immediate implementation. In the process of developing these various assay versions, the timeline for each has accelerated.
The company's work in this area began with an initial proof-of-concept study in lung cancer, followed by the validation of a three-cancer test, which the firm reported at scientific meetings in early 2020.
By late last year, Burning Rock had expanded this to a six-cancer test, with results released at the European Society of Medical Oncology Asia meeting that demonstrated an 81 percent sensitivity and up to 98 percent specificity.
The plan moving forward has been to initiate a prospective interventional study that will prove the validity of this six-cancer test and cement its performance in the asymptomatic population it is intended for, something Chuai said is still being planned.
In the meantime, the firm has moved forward with development of even larger panels.
As it begins recruitment of a new case-control cohort for its 22-cancer panel, Burning Rock is already in the process of evaluating an interim nine-cancer detection assay — targeting lung, colorectal, liver, ovarian, pancreatic, esophageal, gastric, and head and neck cancer, as well as cholangiocarcinomas — in a 14,000-patient trial called the Pan-Cancer Early Detection Project, or PREDICT.
"We have already finished the assay development, which means that we have finalized the chemistry and the marker selection, the panel design, etc. And the analytical validation for that product is currently ongoing, but [as that progresses], we were able to start the enrollment on the case-control study in parallel to shorten the development time overall," Chuai said during the call.
"Then for the 22-cancer test, we are actually still working on developing the next generation of the product. However, because we collected a lot of information or preliminary results from the previous versions of the [test], we were able to finalize the design of [the new] PRESCIENT study. So that's why we have kicked off the enrollment, so we [can] recruit clinical samples for future validation in parallel with our product development efforts."
"Compared to PREDICT, PRESCIENT actually has two dimensions of expansion," Chuai added. One is to go from nine to 22 cancer types. In addition, PRESCIENT will evaluate, in its training phase, not only the methylation and protein markers employed in PREDICT but also other "omics biomarkers." The firm is not disclosing much detail on these new targets, she said, but they are either genetic or epigenetic signals.
As this moves forward, Chuai said the PREDICT trial, using Burning Rock's nine-cancer test, is progressing as expected. About half of the 14,000 cohort will be made up of cancer patients, another 10 percent will be individuals with benign diseases, and the rest well be healthy controls.
"At least 75 percent of the cancer participants will be from stage I, II, and III," she added. "We wanted to be able to assess our sensitivity among the early-stage patients because that's what really matters."
She also stressed that participants are being followed for 12 months after testing, including the healthy controls, which means that the company will be able to read out a positive predictive value.
Burning Rock expects Phase I enrollment for PREDICT to complete by 2022, with a data readout by the end of 2022. "By the end of 2023, we will have the readout for Phase II data, and by 2024, we will be able to finish the follow-up," Chuai said.
For the newly added PRESCIENT study, "we expect to complete the enrollment by 2023, and … by the end of 2023, we expect to be able to lock the model from the training set, and then in another year have the study readout for the validation set," she added.
According to Chuai, Burning Rock doesn't expect the PREDICT or PRESCIENT studies to be sufficient for seeing its technology through to the clinic for screening an asymptomatic population.
For the firm's earlier six-cancer test, however, Burning Rock is close to beginning a study powered sufficiently to give an answer about test performance in an asymptomatic population, which could potentially support a regulatory submission.
That said, the registration pathway for early-detection products in China "is not anywhere near crystal clear," Chuai said. "At this point, we're having a conversation with [the National Medical Products Administration], so we don't know 100 percent yet that [that study] will be enough, but at least it's powered to answer the question … whether the benefits would be enough … as a pay-out-of-pocket product."
"Then for reimbursement, you not only have to establish an individual-level benefit, you have to establish a population-level benefit, so in order to do that, there is a lot more we'll need to evaluate beyond just sensitivity and specificity on that individual level … but in China, the market is [largely] an out-of-pocket market," she added.