NEW YORK (GenomeWeb) – Diagnostics developer OncoCyte provided an update on its test development activities last week, highlighting encouraging recent results for its breast cancer test, providing an update on its bladder cancer test, and announcing a slight delay for the lung cancer test it intends to launch this year.
Last fall, the company and its academic collaborators at the Wistar Institute presented data from a 600-person study on the lung cancer test — which measures a panel of mRNA markers to predict which patients with positive imaging have benign versus malignant nodules — at the American College of Chest Physicians annual meeting in Los Angeles, with plans to get it on the market by the second quarter of 2017.
The company has meanwhile been working on a new study to replicate and validate the results that came out of Wistar. OncoCyte first partnered with the institute in 2013, but only signed an exclusive licensing agreement for the lung cancer test last year.
Last week, the company shared an update on this 300-patient study, saying that because of delays in collecting malignant samples, it now expects to finish the analysis by the end of the first quarter of 2017 — about a quarter later than its original target date.
That should still allow the firm to launch the test this year, as long as the study is successful in demonstrating sufficient sensitivity and specificity.
The lung test is intended as a confirmatory tool, used after a positive screening result — in this case, a lung nodule discovered via imaging — to help pick out patients who can avoid further interventions, whether additional imaging or biopsy procedures.
A test in this setting needs to be very sensitive — to avoid false negatives — but doesn't have to have as high a specificity, since the lung imaging itself has such low specificity, the company has said — in its update last week, Oncocyte said that based on a market research study of 180 physicians it completed in December, it believes that a successful test would need to have sensitivity of at least 85 percent and specificity of at least 30 percent.
In the data presented by the company with Wistar last year, researchers reported a sensitivity of 90 percent and specificity of 62 percent, so the firm is hoping it will see at least close to those levels in its current validation.
With work to prepare the test for commercial use going on in the background, the other major hurdle for OncoCyte this year is obtaining CLIA certification. The company said last week that its lab equipment has been qualified for clinical use, and the lab is fully staffed with a board-certified clinical lab director, a clinical supervisor, and a licensed technologist.
As soon as the study is complete, the firm will apply for CLIA certification, and will then begin a CLIA validation study using a finalized processing algorithm and operational procedures with a new set of at least 300 blinded samples.
Meanwhile, OncoCyte has been working on two other assays — one for breast cancer and one for bladder cancer. Last week, the company said that it has begun a biomarker training and optimization study for the breast cancer test using blood samples from 300 patients.
Breast cancer
With the newly announced study, OncoCyte hopes to reconfirm positive findings presented at the San Antonio Breast Cancer Symposium last month, CEO William Annett said in an interview this week.
In that proof-of-concept study, researchers assayed 50 benign and 50 malignant samples, using a panel of 15 serum protein biomarkers.
The assay, similar to the company's lung cancer test, is designed to be confirmatory — in this case, to noninvasively detect breast cancer in patients with positive mammogram findings, specifically, patients with a score of 4 based on the Breast Imaging Reporting and Data System (BI-RADS).
According to OncoCyte, the standard of practice is for BI-RADS category-4 patients to be referred for a follow-on biopsy. However, only about 20 percent of these biopsies result in a cancer diagnosis.
At SABCS, researchers reported that OncoCyte's 15-marker assay could detect cancer with 90 percent sensitivity and 76 percent specificity, suggesting that it could help distinguish which women must get a biopsy, and which might avoid it.
Annett said the company expects to complete its new 300-patient study sometime in the middle of 2017, which is ahead of schedule and could allow it to commercialize the test by the end of 2018.
Similar to the lung cancer test, the company said it plans to follow up the current study, if successful, with a second algorithm validation and then a clinical validation in its CLIA lab.
Unlike the RNA-based lung cancer test, the breast cancer test is protein-based and uses a different platform.
For the data presented at SABCS, Annett said, the company used Somalogic's SOMAscan technology. The lung cancer test runs on NanoString's nCounter gene expression analyzer.
According to Annett, OncoCyte hasn't determined whether it might try to translate one of the assays so that it can run both assays on the same platform. "It really depends on what gives the best results," he said.
Overall, Annett said, the confirmatory testing space has emerged as a central focus for OncoCyte's efforts because it offers an attractive value proposition to payors, clinicians, and patients through the reduction of unnecessary invasive or expensive procedures.
Confirmatory testing is the focus of significant attention in both lung and breast cancer, with other players that could provide competition for OncoCyte, although some test makers have faced hurdles in advancing tools in this setting.
Integrated Diagnostics, for example, is hoping a recent draft guidance from Medicare contractor Palmetto GBA proposing coverage for the second generation of its multiple-reaction monitoring mass spec-based Xpresys Lung test can help it avoid the slow sales it saw for the first version of the assay.
Bladder cancer
In addition to news on its two confirmatory tests, OncoCyte also shared an update on its bladder cancer diagnostic.
The company presented its most recent data on that test last June at the annual meeting of the American Society of Clinical Oncology. In a 241-patient study, the firm demonstrated the feasibility of its urine-based approach to detect bladder cancer and to distinguish between high-grade and low-grade cases.
An assay for the detection of high-grade urothelial carcinoma performed with an area under the receiver operating curve of 0.93, while a panel for low-grade carcinoma performed with an AUC of 0.81.
Because of the potential for a bladder cancer diagnostic to be used not only by specialists, but also by primary care physicians, OncoCyte is hoping to partner with a company with a larger sales force that could handle the broader marketing involved.
OncoCyte also continues to examine strategies, including partnering the product, to fund late stage development and commercialization of the bladder cancer test.
Annett said that the company has also had interesting results applying the test not for diagnosis, but for detecting recurrence post treatment, which it is exploring further.