NEW YORK – With the launch of a new nationwide real-world evidence registry, Oncocyte wants to bolster validation data supporting the use of its 14-gene expression assay, DetermaRx, as a predictive tool for guiding adjuvant treatment in early-stage non-small cell lung cancer.
The company hopes the additional evidence collected through the registry will drive adoption among oncologists and improve the test's reimbursement prospects.
The prospective registry, dubbed Predictive Assay for Decision Making in Adjuvant Therapy, or PADMA, will enroll 1,000 patients with surgically resected stage I and IIA NSCLC from academic and community cancer centers across the US. Patients who agree to partake in the registry will have their lung tumor sample tested on Oncocyte's PCR-based gene expression assay DetermaRx, for which it garnered development and commercialization rights from Razor Genomics in 2019.
Roughly two weeks after testing, doctors will receive the results indicating whether their patients' cancers are high or low risk for recurrence, which the company hopes will influence whether they are treated more aggressively with adjuvant treatment or just followed closely. Because the registry is observational and collecting real-world evidence, the treatment decision remains up to the physician and patient. Patients who are at high risk of recurrence according to DetermaRx could elect to hold off on additional therapy, while those deemed to have low-risk tumors may elect to undergo additional therapy.
Oncocyte expects that about 40 percent of early-stage NSCLC patients tested on DetermaRx will be deemed high risk, according to Kimberly McGregor, Oncocyte's VP of medical affairs. Patients who elect to have post-surgery treatment, she explained, could have a number of options depending on their tumor characteristics. They could opt for adjuvant chemotherapy or a targeted therapy like osimertinib (AstraZeneca's Tagrisso) if their tumor has an EGFR mutation.
After patients receive their DetermaRx results and decide on the next course of treatment, Oncocyte will collect this data, as well as their treatment outcomes in the PADMA registry. McGregor doesn't expect the data collection component to burden patients with too many additional visits. "It's really that one visit to offer the test and enroll them, then the second visit to go over the results, have that informed decision-making process with their doctor and then go from there."
Every six months over a period of 18 months, patients will see their doctors, who based on these visits will submit certain information to Oncocyte's registry, for example, what treatment patients received, whether they completed the full course of treatment, and whether they are still in remission or have evidence of disease recurrence.
Oncocyte is working with surgeons to collect the registry data, because while all early-stage NSCLC patients will have to see a surgeon to remove their tumors, there aren't clear guidelines on the need for additional therapy post-surgery. As such, not all patients are referred to medical oncologists.
For this same reason, encouraging adoption of DetermaRx among oncologists will require more education and validation data, McGregor suggested. "Our goal here is to increase awareness of the test itself and increase comfort in using it," she noted, explaining that many oncologists would like to see further validation data supporting the test.
To date, prospective validation data for DetermaRx have been encouraging, but limited. Last fall, the firm presented data from a cohort of 250 stage I-IIA non-squamous NSCLC patients, all of whom had been enrolled from a single trial site. For the PADMA registry, in contrast, Oncocyte expects to enroll over 1,000 patients from sites across the country.
Added utility with EGFR testing
For the smaller prospective study presented last fall, Oncocyte tracked patients' freedom from recurrence and disease-free survival to assess the performance of DetermaRx. After 29 months, 95 percent of patients who were molecularly low risk according to the test were free from recurrence, compared to 72 percent of high-risk patients who did not receive adjuvant treatment. In comparison, when high-risk patients received adjuvant chemo, 97 percent were free from recurrence.
In this earlier study, Oncocyte also considered the impact of EGFR mutation status. Among 56 patients with EGFR-mutated NSCLC, their mutation status wasn't significantly associated with the likelihood of disease recurrence, and the DetermaRx could predict survival outcomes and adjuvant chemotherapy response just as well in this subset as those with wild-type EGFR status. Based on this, Oncocyte determined that the predictive power of its test was independent of EGFR status.
While this study was wrapping up, AstraZeneca's ADAURA trial demonstrated that EGFR-mutated, early-stage NSCLC patients derived a disease-free survival benefit from adjuvant osimertinib compared to placebo. Although eligible patients in Oncocyte's validation study did not receive adjuvant targeted therapy, since then, the US Food and Drug Administration has granted accelerated approval to osimertinib based on ADAURA. Because of this, Oncocyte has decided to pair EGFR testing with DetermaRx to give patients and providers even more data to help make adjuvant therapy decisions.
According to McGregor, many patients enrolling in the PADMA registry will likely already know their EGFR mutation status through their cancer centers, since many are performing such testing in-house. But those who have not been tested for EGFR mutations can learn their biomarker status through Oncocyte when it performs DetermaRx. To improve turnaround time, Oncocyte is in the process of partnering with an undisclosed lab close to its own to perform EGFR testing.
Bringing payors on board
Oncocyte pivoted to focus on driving adoption and increasing revenues for DetermaRx last year after discontinuing efforts to commercialize its lead blood-based lung cancer detection assay, called DetermaDx, due to validation difficulties. The company hopes that based on evidence from the PADMA registry, organizations like the National Comprehensive Cancer Network, or NCCN, will incorporate DetermaRx as a tool for guiding post-surgical treatment options in guidelines.
"At this point, there's no molecular assay in the guidelines for early-stage lung cancer," McGregor said, explaining that guidelines currently recommend using clinical pathological features to stratify recurrence risk and adjuvant chemo benefit for early-stage NSCLC patients. However, she highlighted that in past studies Oncocyte has been able to identify molecularly high-risk patients who, based just on their clinical pathological disease features, would have been low-risk according to the guidelines.
"We've submitted [DetermaRx data] to NCCN, and that's usually the next step for people to be adopting a test more comfortably," she said. "Getting in the guidelines could be very impactful in terms of [additional commercial payors] understanding the value of the test."
Although PADMA is technically a trial, the test isn't free for participating patients, who will either have to pay for a portion of the test out of pocket or have it reimbursed through insurance.
Currently, the test has Medicare coverage, which came after Medicare contractor Palmetto issued a final local coverage determination last year. Among the coverage criteria, Palmetto states that DetermaRx must be ordered by a doctor treating the patient and trying to decide whether to recommend adjuvant chemotherapy.
Padma Sundar, Oncocyte's chief commercial officer, estimated that roughly 70 percent of the patients eligible for DetermaRx are eligible for coverage under Medicare. For those covered under private or commercial plans who receive denials, Oncocyte offers financial assistance through a program that, according to Sundar, has ensured that no patient has ever paid more than $199 for the test out of pocket. She did not disclose the list price of the test because Oncocyte is in the midst of negotiations with commercial payors.
According to Oncocyte, several commercial payors have begun to cover the test, but McGregor acknowledged that many commercial payors make coverage decisions in accordance with national guidelines, which as of now do not include DetermaRx for early-stage NSCLC. Additionally, commercial payors don't always align coverage determinations with Medicare.
Oncologists, guidelines bodies, and payors may be particularly interested in the data from the PADMA registry, since for a significant number of patients the test might indicate more treatment, where previously they would have just been followed closely. This can be perceived as adding costs to patient care compared to other settings like early-stage breast cancer, where gene-expression recurrence tests are seen as tools to identify patients who can avoid additional chemotherapy.
Proving the value of DetermaRx to commercial payors, accordingly, means proving that giving certain patients additional therapy would be cost saving in the long run because patients would theoretically experience improved outcomes and survival.
"These early-stage patients are potentially curable. That's where we could affect the five-year survival," McGregor said, noting that stage I lung cancer patients have a poorer five-year survival than patients with other types of cancer, and there's been very little progress in those metrics in the last decade. "This is the value point payors will be able to see when we have more data from this larger cohort."