NEW YORK – Cancer detection firm Naveris is hoping for continued adoption of its assay for HPV-associated head and neck cancer recurrence this year as it explores additional use cases for its technology with multiple academic groups.
Despite launching the assay, called NavDx, shortly before the beginning of the coronavirus pandemic, the firm has seen significant growth, CEO Piyush Gupta said this week, with about 90 medical centers and over 130 physicians now using the test to surveil their patients for recurrence after initial surgery and other early treatments.
This growth has been supported by a $17M Series A financing that the company announced in December but the majority of which closed earlier in 2020.
"The fact that physicians are using us … is meant to be a proxy for something that really matters, which is the benefit provided to patients," Gupta said. "The thing that has [us] excited is that we have been able to provide information to physicians that they would not have had otherwise"
Naveris' test — which was developed initially by investigators at the University of North Carolina — uses digital PCR to detect target DNA sequences shed from human papillomavirus-linked head and neck cancers. It is intended to help physicians identify which patients with these tumors are free from cancer after initial treatment and which might be poised to relapse.
Unlike liquid biopsy methods that search for mutations in circulating tumor DNA, NavDx picks up tumor-derived fragments of HPV DNA. Importantly, it is able to distinguish this signal from viral DNA that would be present in an active infection.
According to Gupta, approximately 85 percent of patients with early-stage head and neck cancers caused by HPV are cured by their initial treatment, while 10 to 15 percent eventually recur. But unlike many other cancer types, recurring HNC patients can still be cured with additional treatment if these tumors are found early.
There are two methods that have been used to surveil patients thus far, Gupta said. One is nasopharyngeal endoscopy using a fiber optic scope and the other is radiographic imaging.
Both leave significant room for improvement, he argued.
Recent research has shown, for example, that while nasopharyngeal endoscopy works well for detecting large primary tumors, it has little to no utility for detecting early recurrences, which can present as very small lesions.
Imaging, meanwhile, works "extremely well," Gupta said, but only if you look in the right place. And while the majority of recurrences happen in the same head and neck area, 25 percent or more can occur in the lungs or even at distant sites in the body.
"What we have found is that there have been a number of cases … I would say they happen almost once every week now … where a physician is monitoring a patient and the chart says 'no evidence of disease' after therapy but our blood test shows a positive result" he added.
Overall, Gupta said this is happening in about 2.5 percent of the cases it sees, and so far, every patient who has been brought in for a full body scan based on a positive NavDx test result has indeed had a recurrence despite negative results from either endoscopy or localized imaging.
"Three weeks ago we had an example of a physician who had sent in the first test months ago and it was positive," Gupta said. " He ran a second test and it was slightly more positive. He ran a scan and he found a seven-millimeter pulmonary nodule and when it was biopsied, it turned out to be a recurrence."
"That's what we are hoping to see and we're seeing it frequently enough now that it's got us very excited," he added.
Over the next year, Naveris is hoping to publish case reports on some of these individual outcomes, as well as at least two large studies aggregating and analyzing its full cohort of clinically tested patients to calculate the test's overall sensitivity and specificity.
In the prior study published by the initial developers at UNC, NavDx was highly negatively predictive. None of the 87 patients who maintained fully negative HPV blood tests had a recurrence.
The test also showed 94 percent sensitivity and specificity as long as two positive test results in a row were set as a threshold for predicting recurrence.
Much of the recent excitement around blood-based cancer screening and surveillance has been focused on pan-cancer technologies like those being developed by Grail and Thrive. But Gupta argued that different clinical niches and use cases are unlikely to be served equally by a single technology.
"There are a lot of folks aspiring to solve this problem and I don't think there will be a one-size-fits-all solution," he said. "If you're going for screening in the general population... a sensitivity of 50 percent or specificity of 95 percent isn't so bad. But if you want to know if a patient that has had cancer should be rescanned to look for a recurrence, it's not clear whether a 50 percent sensitivity really is actionable."
Reflecting the reality of diverse needs in early detection and recurrence monitoring, Naveris is very much not alone in pursuing solutions specific to viral cancers. Among other leading efforts, Chinese University of Hong Kong investigator Dennis Lo has pioneered methods for Epstein-Barr virus nasopharyngeal cancers, while other groups have targeted liver cancers that arise from viral hepatitis and even EBV-associated childhood lymphomas.
Having launched a research lab last year, Naveris is now exploring its own options for expanding its HPV-focused method to new niches, with 13 research studies in the works led by a variety of academic partners.
Although Gupta said he couldn't disclose specific projects, the company is being guided by clinicians to see if the same detection technology that allows post-treatment surveillance can also address other unmet needs both in HPV-associated head and neck cancer and potentially other tumor types like cervical cancer that are caused by the same virus.
Likely targets may reflect those being pursued by other groups in the field, such as the application of liquid biopsy technologies to alternative fluids like saliva instead of blood. Researchers in the field are also exploring whether viral tumor DNA assays could indicate that patients are responding to a particular treatment or guide decisions about who should receive adjuvant therapy after surgery and who can avoid it.
For example, investigators from Memorial Sloan Kettering have previously explored using droplet digital PCR to detect early-stage HPV-associated cancers, a low-cost approach they believe could be used for frontline screening and longitudinal monitoring of treatment responses, and researchers from Toronto's Princess Margaret Cancer Center have explored using HPV DNA sequencing assays to monitor cervical cancer patients for signs of minimal residual disease.
In the meantime, Naveris is hoping that publishing updated data from its clinical cases this year will help further accelerate adoption and build evidence to support insurance coverage for its core head and neck cancer surveillance application.
"It was hard for us to know what that threshold for evidence would be across the community when we first launched," Gupta said. "In the early days there was no question that there was a group of physicians that … saw the Journal of Clinical Oncology publication … and said this is information that only helps and I'm going to try to use it."
"There are others that take more of a wait-and-see approach … [but] I would say it's been shifting as we start to demonstrate true clinical value."
Currently there is one undisclosed national payor that the firm has "good coverage" with, and although conversations slowed during the early stages of the coronavirus pandemic, Naveris is working on persuading additional insurers. In the meantime, the company does not charge patients out of pocket who are unable to obtain reimbursement through their policy.
As it amasses clinical case data Naveris may also be able to tease out new evidence to support novel standardization or best practice recommendations for blood-based surveillance —something Gupta said the field has struggled with thus far even with legacy screening technologies.
Currently the frequency at which doctors order tests depends on the particular physician or practice, but typically patients are tested about once every three to four months. Gupta noted that Naveris needs to gather data to better determine the appropriate number of tests per year.To support all of these efforts the firm will have to raise additional funds, and is in discussions with investors for a potential additional financing round this year, Gupta said.