NEW YORK (GenomeWeb) – Mitra Biotech, which recently announced it has received CLIA certification for its Woburn, Massachusetts-based lab, this month began offering its CANScript test in the US through an early-access program.
The CANScript platform replicates a cancer patient's tumor microenvironment and predicts which treatments will improve outcomes. Specifically, CANScript creates an ex vivo tumor ecosystem that closely resembles how a patient's tumor looks and acts inside the body.
Using this model, physicians can test how different treatments they are considering for patients impacts factors indicative of tumor response, such as cell proliferation and death. The findings are then evaluated by a machine learning algorithm to calculate a score that corresponds to how likely a patient is to respond to a specific drug or regimen.
Parker Cassidy, Mitra's chief commercial officer, said in an interview that the company is providing oncology practices with early access to CANScript to generate clinical utility data that will support a wider commercial launch for the platform in the US and other markets.
In 2015, the company published a clinical validation study in Nature Communications, where researchers used CANScript on samples from patients with head and neck squamous cell cancer and colorectal cancer. Although at this validation stage the test wasn't used to guide treatment strategies for patients in the clinic, it demonstrated 91.67 percent specificity and 100 percent sensitivity in predicting how these patients actually responded to the treatment they received.
Mitra says it has continued to develop and validate CANScript on more than 2,000 clinical cases across different solid tumors and hematologic malignancies, and is working on publishing that data. Meanwhile, the company is now turning its attention to gathering the clinical utility evidence that will be critical for demonstrating value to payors and driving CANScript's adoption among clinicians who are looking for tools to personalize cancer treatments for their patients.
According to Cassidy, Mitra and its partners will be focusing on demonstrating the utility of CANScript in clinical scenarios where doctors face a "fork in the road," where there are different treatment options that they could give their patients supported by guidelines, US Food and Drug Administration approval, or care pathways approved by payors or within their practices.
"They've got a choice to make but no really good tools to help them tease out which is the most effective path for an individual patient," he said. This is not an uncommon scenario for oncologists, particularly when treating advanced metastatic cancer patients who are considering systemic treatment.
For example, in colorectal cancer, Cassidy offered, where studies have shown that chemotherapy regimens FOLFOX and FOLFIRI are equivalent on a population level, clinicians have seen varying responses to these regimens in individual patients. Similarly, in non-small cell lung cancer, after patients have exhausted targeted treatment options or don't have any targetable tumor mutations, their choices are different chemo regimens with low response rates.
Mitra plans to support its clinical utility studies and reimbursement for CANScript with proceeds from a $27.4 million funding round last year. The money will also go toward expanding its team in the US and in India, where the company is offering CANScript in several cancer hospitals in larger cities.
In the US, CANScript is becoming commercially available at a time when a number of top cancer centers around the country are using genomic profiling tools to home in on the right treatment strategy for their patients. At the Personalized Medicine World Conference in Mountain View, California, earlier this year, Cassidy discussed how genomic profiling hasn't yet lived up to the excitement it initially generated in the cancer community. "There's been tremendous progress in the personalization of care for cancer patients, but there's still a gap in the reality that exists for a cancer patient and the perception," he said at the conference.
He cited a study published in 2015 by Funda Meric-Bernstam and colleagues from MD Anderson Cancer Center, which reported that out of 2,000 patients who received genomic testing at the facility, 39 percent had an actionable mutation, but only 4 percent were able to be enrolled in a trial based on their cancer's genomic characteristics.
Other groups in the US have published data or shared experiences that similarly suggest that most cancer patients do not have a tumor marker for personalizing treatment and, even when there is a targetable marker, don't always benefit from treatment. Around the time Meric-Bernstam et al. published their data in September 2015, Cassidy said he decided to join Mitra, which is trying to disrupt precision cancer care through CANScript.
According to Mitra, CANScript returns results in seven days, and can inform treatment strategies across drug classes, including chemotherapy, targeted treatments, and checkpoint inhibitors. Cassidy said at the PMWC that in the clinical setting, the platform can deliver actionable results for almost 75 percent of patient samples that Mitra receives.
Raanan Berger, director of the Oncology Institute at Sheba Medical Center in Israel and a member of Mitra's advisory board, said his institute has sent 20 patient samples for analysis by CANScript and he has found the platform's predictive accuracy to be "very high."
Comparatively, he's not so enthused about genomic profiling. "My experience, which I share with a lot of other medical oncologists, is that the genomic panel platforms serve very, very few patients at present," he said in an email. "The only patients that are benefiting from this approach in high percentage are the lung adenocarcinoma patients."
He estimated at the PMWC that 10 years ago only 15 percent of patients with lung adenocarcinomas received targeted therapies, but now, because of next-generation sequencing approaches, more than 50 percent of patients can go on such drugs. Outside this setting though, NGS hasn't really guided his patients toward better outcomes, Berger said.
Still, when his patients come to him having heard of NGS, and are eager to have it, he does send their samples for genomic profiling. "So, I do send them for next-generation sequencing, I do get the results, and sometimes I do give them the treatment, and sometimes they need to pay a lot for this," Berger said at the conference. "But again, most of the time, it doesn't work."
Comparatively, he cited the single case of a 49-year old female patient with head-and-neck cancer, for whom CANScript gave a positive predictive score for five of the eight treatments under consideration. She ended up getting carboplatin plus paclitaxel, which was one of the regimens CANScript gave a very high score to, suggesting she would likely experience a complete response, and she did.
Berger cautioned that as with genomic profiling tools, the clinical data on CANScript is also emerging, and there is no survival or progression-free survival data yet. He also threw out a few caveats for physicians.
Usually there is enough tumor tissue to try out between four and eight treatment strategies on the CANScript platform. But the patient needs to be healthy enough to undergo biopsy, according to Berger, and doctors should prioritize a few drugs for testing in case there isn't sufficient tissue to run all eight tests.
"A major task for the physician is to decide which treatment options to test" on CANScript, and this is not always clear, he added at the conference. Then, if CANScript gives positive scores for multiple therapies the doctor is considering, it may be a challenge to figure out which to go with for a particular patient. And sometimes none of the treatment options come back with positive scores, raising additional questions, Berger noted.
These considerations will certainly play a part in the clinical utility studies that Mitra will be doing with early-access users of CANScript. Meanwhile, Mitra is also starting to work with pharmaceutical companies to explore if CANScript can make the drug-development process more efficient by helping decide which indications or combination of drugs to advance in the pipelines, and to inform biomarker strategies.
Developers of immuno-oncology treatments have shown interest in using CANScript, Cassidy said, since there aren't good model systems to test such agents during the development process. "There are probably more drug combinations being studied than there are patients to study them in," he said. "So, you need surrogates and model systems that help prioritize those different hypotheses."
Mitra hasn't yet publicly disclosed any of its biopharma collaborations around CANScript, but Cassidy said several partners will soon publish data on their experiences using the platform.