NEW YORK – Oncocyte said earlier this month that it had launched its immunotherapy response prediction assay DetermaIO through an early-access program, with plans to provide the assay more widely next year.
On a call this week discussing the firm's Q3 financial results, CEO Ron Andrews added that that test will be joined in the first quarter of next year by a complementary assay, DetermaTX, which is designed to inform personalized treatment strategies using molecularly targeted drugs and will be able to be performed on the same tissue samples submitted for DetermaIO.
Oncocyte believes the two assays can provide a package deal to compete against established therapy selection assays for advanced cancer patients in a market Andrews estimated at close to $5 billion.
Currently, oncologists can order any of several comprehensive genomic assays to access genetic markers informing targeted therapy and information about immunotherapy sensitivity via either microsatellite instability status or tumor mutational burden, both of which are recognized by the FDA as companion diagnostic markers for the immunotherapy pembrolizumab.
If a physician wanted to know a patient's PD-L1 status, also an official CDx biomarker for several immunotherapies, they'd have to order that test separately.
Oncocyte has described DetermaTX as a 500-gene next-generation sequencing assay, and as such, it mirrors many of the existing options already on the market. However, the company is hoping to differentiate itself by pairing DetermaTX and DetermaIO to better predict patients' immunotherapy sensitivity than other assays.
Brought in with Oncocyte's acquisition of Insight Genetics, DetermaIO is a PCR-based gene expression test performed on tissue samples to generate molecular signals from the immune microenvironment.
Oncocyte has collected data from clinical studies evaluating hundreds of patients across multiple tumor types, including lung, breast, bladder, and renal cancers, which suggest that the test can predict response to immune checkpoint inhibitors more accurately than PD-L1 and, potentially, TMB.
"In less than two years, we have validated the analytical reproducibility, completed CLIA validation, and completed clinical validation across four major solid tumors. We've now tested over 1,000 patients to date," Andrews said.
In an email, he highlighted data in bladder cancer, which showed that the addition of DetermaIO to TMB helped identify 19 percent more patients with no statistical change in overall survival.
"These biomarker selected patients had a significant improvement in OS compared to unstratified patients," Andrews said.
In another recent presentation from the NeoTrip trial, investigators randomized triple negative breast cancer patients to receive either neoadjuvant chemotherapy alone or chemotherapy combined with an immune checkpoint inhibitor. In this cohort, DetermaIO positive patients had a 20 percent higher pathologic complete response when an ICI was added to standard of care chemotherapy, while those who were DetermaIO negative showed no additional benefit from the addition of immunotherapy to a standard of care regimen.
"Demonstrating the utility of DetermaIO in the rigorous setting of a randomized, therapeutic clinical trial is a landmark accomplishment," Andrews said.
Although the company has published some studies to date, much of this newer data on DetermaIO has been limited to conference presentations, so establishing a deeper well of clinical evidence in the peer-reviewed literature remains a goal.
According to Oncocyte, providing select physicians with early access to DetermaIO ahead of such publications and Medicare reimbursement reflects the company's desire to meet immediate demand for the assay.
The early-access program is targeting academic sites that have partnered with the company on prior clinical research, and will allow Oncocyte to optimize things like sample processing and logistics ahead of a wider launch.
"We believe we have the data today to go to market clinically. We've got enough in the tumors that we validated already to go," Andrews said. "Historically in our industry, [numerous] companies have launched their test ahead of reimbursement and have moved towards adoption. So we realize that we still have a little bit of a road ahead for reimbursement, but especially given that DetermaIO is a PCR test, we believe it's prudent to go ahead and launch it and start the clinical adoption process."
Padma Sundar, Oncocyte's chief operating officer, said that recruitment for the early-access program is ahead of schedule and clinical samples are expected to begin coming in before the end of this year.
In a statement provided as part of Oncocyte's launch announcement for DetermaIO, Nagdala Abdel-Karim, director of the Thoracic Oncology Multidisciplinary Clinic and medical director of the Georgia Cancer Centers Clinical Trials Program, said that she has been impressed with the existing DetermaIO data.
"For my patients with lung cancer, there are myriad treatment options … each with their benefits and risks in terms of toxicity and side effects. Therefore, selecting the right immunotherapy regimen for the patient is a very complex decision. We use PD-L1 and occasionally tumor mutational burden, but neither biomarker is completely accurate or takes into account both the tumor and its microenvironment, which is important as both determine response to immunotherapy," Abdel-Karim said.
The wider oncology community may require more definitive data, ideally prospective studies, showing that the assay better identifies immunotherapy responders and non-responders than FDA-approved biomarkers, especially considering the leg-up existing comprehensive genomics assays may have in market penetration.
According to Andrews, Oncocyte expects to be able to deliver a reimbursement dossier to its Centers for Medicare and Medicaid Services contractor for DetermaIO in the first half of 2022, aiming to see the test generate revenue alongside DetermaTX as soon as possible.