Blood Test to Predict Response to Immune Checkpoint Inhibitors
Featuring: Rob Kimmerling, PhD, Dennis Watson
In short
A blood test developed by Travera analyzes individual immune cells to predict whether a patient's immune system is fit enough to respond to immune checkpoint inhibitor drugs — before treatment begins. More than 40% of cancer patients are eligible for these drugs, but fewer than 20% experience lasting benefit, so this test aims to help patients and doctors make better-informed decisions about which drug to try, whether to combine drugs, or whether to skip them altogether.
- •Ask your oncologist whether your current biomarker testing looks at your tumor only — this test looks at your immune system instead, which is a different and complementary piece of information.
- •If you have melanoma or a cancer type that can be MSI-high (such as colon, rectal, esophageal, gastric, renal, or bladder cancer), you may be a good candidate for this test.
- •Travera is currently offering the test at no cost through an Early Access program — a doctor's order is required, and you can contact Dennis Watson at dwatson@travera.com to get started.
- •Results come back to your doctor in about three days from a standard blood draw, so it adds minimal delay to your treatment planning.
Watch on Cancer Patient Lab YouTube
Ask anything about this — free, no signup
Instant answers grounded in real guidelines, not the internet.
Brad Power July 16, 2025 “These immune checkpoint blockade drugs are used very widely now, so over 40% of patients are now eligible for these therapies, meaning they have some kind of biomarker in their clinical workup, that means they are eligible to receive immune checkpoint blockade.
Unfortunately, only about 20% of patients that receive these drugs actually have a durable clinical benefit from them, and this comes, oftentimes with a lot of pretty harsh side effects as well. ” – Rob Kimmerling, PhD “One of the big challenges when thinking about cancer is often this idea that within a tumor there's a lot of variability of every cell that's in that compact tumor.
So a big challenge with therapies often is that a drug might only kill a few of those cells, not all the cells. For our version of testing, we take that tumor and break it down to all of its components, those single cells, those individual actors, and we're trying to test those cells to see which ones respond to therapies.
” – Rob Kimmerling, PhD “At its baseline, does a patient have T cells that are fit enough to actually mount a response to kill a tumor? And more specifically, are their immune cells specifically sensitive to different immune checkpoint blockade drugs? That's really the question we're trying to answer with our testing.
Meeting Summary
Immune checkpoint inhibitors are transforming cancer therapy with expanding applications. These drugs help your immune system recognize and attack your cancer cells, some by blocking checkpoint proteins that inhibit your immune response to cancer.
Today, more than 40% of cancer patients are eligible for these immune checkpoint blockade drugs, but fewer than 20% benefit, highlighting the need for better predictions of patient responses to these drugs. Current predictive tests leave opportunity for improvement in identifying whether you will likely benefit from this therapy. They focus on your tumor characteristics rather than your immune system readiness.
Rob Kimmerling, PhD, Co-Founder and their Chief Technical Officer at Travera, and Dennis Watson, Vice President of Business Development at Travera, are uniquely qualified to discuss ways you can personalize your immune checkpoint inhibitor treatments by predicting your likelihood of a positive response. Rob started in a lab at MIT where Travera’s unique weighing technology was developed for “functional testing”.
Dennis has been working in genetics and genomics of cancer for nearly 20 years. Travera’s new immune system test is built on a novel advanced technology that analyzes the immune cells in your bloodstream to personalize treatment.
It’s the first CLIA-approved test assessing baseline immune cell fitness, which can provide insight on your immune system's readiness for activation, while also functionally measuring which of the most commonly used immune checkpoint inhibitor drugs will do the best job of activating your immune cells. Why does knowing about your immune system health matter when you are considering immunotherapies, especially immune checkpoint inhibitors?
•Not all patients respond equally to immune checkpoint inhibitors. Currently, only about 20% of patients receiving these drugs experience a durable clinical benefit.
•Understanding your immune system's baseline fitness can help predict whether you're likely to respond to a specific immunotherapy drug.
•It can guide personalized treatment decisions, such as choosing between different checkpoint inhibitor drugs, deciding whether to combine drugs, and determining whether to continue or discontinue a particular therapy.
•It provides insights beyond traditional tumor-based biomarkers by assessing the functional capacity of your immune system to mount an effective response against cancer.
•It can help avoid unnecessary treatments with expensive drugs that are unlikely to be effective for your specific immune profile, potentially saving time, resources, and reducing side effects.
•It could help you monitor your immune system changes by taking longitudinal blood draws and measuring T-cell physical parameters like mass, volume, and density. By taking blood samples at different time points after interventions (like supplements, exercise, or lifestyle changes), you could track how these activities impact your immune cell fitness.
•Combining it with your molecular profiling and gene expression data, you can better understand the longitudinal profile of your immune system. Who should ideally get a single cell immune system analysis of their blood?
•Melanoma patients considering immune checkpoint blockade therapy
•If your tumors are characterized by a high degree of DNA instability – microsatellite instability high (“MSI high”) – they are more likely to respond to certain immunotherapies, particularly checkpoint inhibitors like pembrolizumab. Your MSI status requires tumor tissue.
•Solid tumors that can be “MSI high” include: colon cancer, rectal cancer, esophageal cancer, gastric cancer, renal cancer, and bladder cancer.
•When you are considering multiple equally valid treatment options, such as different immunotherapy drugs,and there is no clear standard approach.
•When you want to understand your immune system's potential response to specific treatments. How can you access this single cell immune system test? What does it cost? Currently, Travera is offering the test through an Early Access program at no cost to patients. The goal is to collect real-world data while helping patients, so they're providing the test free of charge. They're particularly interested in patients with melanoma or other cancers where there are multiple immunotherapy options. To access the test: 1.Reach out directly to Dennis Watson at dwatson@travera.com 2.The test requires a doctor's order 3.Travera will send a test kit 4.You get a blood draw 5.The sample is sent back to Travera 6.Results are returned to your doctor within about three days How can you learn more about your immune system, immunotherapies, and tests for predicting your response to immune checkpoint inhibitors?
•Consult with your oncologist about existing biomarkers like tumor mutation burden, potential clinical trials for immune response testing, your specific cancer type and immunotherapy options.
•Explore resources to stay informed about the latest immunotherapy research, new diagnostic technologies, and personalized medicine approaches from cancer patient advocacy groups, the National Cancer Institute, academic cancer centers, and trustworthy online medical information sources.
•Consider emerging diagnostic tests like Travera's blood-based immune response test; reach out to Dennis Watson at dwatson@travera.com to discuss the test and potential applications
•See our previous discussions on blood-based tests (“liquid biopsies”), including:
••
•“Using Predictive Biomarkers and Liquid Biopsies to Personalize Treatment for Prostate Cancer”
•• •
•and Michelle Lanman)
••
•The information and opinions expressed on this website or platform, or during discussions and presentations (both verbal and written) are not intended as health care recommendations or medical advice by Cancer Patient Lab, its principals, presenters, participants, or representatives for any medical treatment, product, or course of action. You should always consult a doctor about your specific situation before pursuing any health care program, treatment, product or other course of action that might affect your health. For the video recording of this conversation, please see here. Meeting Notes KEYWORDS Cancer diagnostics, immune system monitoring, immunotherapies, single cell assays, T cells, immune checkpoint blockade, tumor mutation burden, neoadjuvant therapy, clinical validation, biomarkers, patient response prediction, blood test, oncology drug spending, personalized medicine, clinical equipoise. SPEAKERS Rob Kimmerling (52%), Dennis Watson (29%), Brad Power (10%), Allen Morris (4%), Bill Paseman (2%), Richard Anders (2%) CHAT CONTRIBUTORS David Plunkett, Rick Davis, Bill Paseman, Allen Morris, Richard Anders, Ari Akerstein, Dennis Watson, Roger Royse SUMMARY Rob Kimmerling and Dennis Watson of Travera discussed their new diagnostic for monitoring immune system responses to immunotherapies. Travera's technology uses single-cell assays to measure T-cell activation and response to checkpoint blockade drugs, such as pembrolizumab (Keytruda). Early data from 21 melanoma patients showed an accurate predictive value (an “area under the curve” of 0.8), predicting 17 out of 21 responses. The test, currently available through a free early access program, aims to guide treatment decisions by predicting patient response to immunotherapies. Future plans include expanding the data set and exploring combinations with other drugs and targeted therapies. OUTLINE Introductions and Overview of Travera
•This discussion was focused on diagnostics for monitoring the immune system and predicting responses to immunotherapies.
•Travera, had its origins at MIT, with a focus on functional medicine and cancer cell testing.
•Rob Kimmerling, one of the co-founders of Travera, has a background in assay (test) development, particularly single-cell assays for cancer. Single-Cell Assays and Immune Response
•Single-cell assays are a set of techniques used to analyze individual cells, providing insights into cellular heterogeneity and gene expression patterns that are often masked when studying cell populations as a whole. These methods have revolutionized fields like developmental biology, cancer research, and immunology by allowing researchers to examine cellular processes at the most fundamental level.
•Single-cell assays are important in understanding cancer variability and therapy response. They can be applied to the immune system, focusing on T cells and their role in targeting tumor cells.
•Immune checkpoint blockade drugs have a role in reactivating the immune system to fight tumors.
•Single-cell assays measure the physical parameters of T cells to gauge their functional response. Travera’s Technology for Weighing Single Cells
•The test uses a suspended microchannel resonator to measure cell mass and density.
•The core platform can measure cell mass, volume, density, and shape.
•It provides a functional readout of a patient's immune cells. Validation and Clinical Applications
•The early data from a cohort of 50 patients highlights the variability in T cell activation and response to immune checkpoint blockade drugs.
•Collaboration with MGH, focusing on melanoma patients undergoing neoadjuvant therapy and the correlation between blood test results and clinical outcomes.
•Early validation data from 21 melanoma patients shows the ability to predict response to immune checkpoint blockade using blood samples.
•The area under the curve (AUC) metric compares the performance of their biomarker with tumor mutation burden (TMB).
•There is potential to pair blood test results with existing tumor biomarkers to improve prediction accuracy.
•Potential applications for the test include advanced disease management, drug-specific functional readouts, and guiding drug combination strategies. Future Directions
•Travera is running the test through an Early Access program, offering it at no cost to patients and collecting real-world data.
•The test has the potential to be used in various cancer types and the importance of building a larger data set to improve accuracy.
•There is a need for continued collaboration and data collection to refine the test and seek reimbursement.
•There is potential for isolating specific T-cell subsets and ongoing research to optimize the assay.
•The test can predict response to drug combinations.
•Functional tests require live cancer cells.
•The test can be used in non-cancer applications, such as autoimmune disease and transplant monitoring.
Full transcript
Brad Power This is the Cancer Patient Lab, and this is our weekly webinar. Today, we're honored to have Rob Kimmerling and Dennis Watson of Travera with us. They've been working on diagnostics in an important new area, which is monitoring the immune system and doing things to describe whether people are going to be likely responders or responding, or something about the health of the immune system.
Immunotherapies are an expanding area of cancer treatments, so knowing both who should get them and whether they're responding is an increasingly important area. I'm really looking forward to hearing about their new diagnostic and any help they may be providing cancer patients and caregivers in knowing whether immunotherapies are right for them. This is, of course, for information purposes only. This is not medical advice.
We try to arm our patients and caregivers in our community with information that they can take to their medical team. We are a nonprofit 501(c)(3), and we depend on the kindness of donors who help fund our operations so we can bring you webinars like this. It's easy to donate. You can do so on our website, where there's a Donate button.
Dennis Watson
I'm going to start us off real quick, and then I'll turn it over to Rob, just with a couple of sort of quick, quick notes from our side. For those of you that are unfamiliar with us, Travera spun out of MIT. Rob will introduce himself in a minute, but he is one of the technical co-founders of the company. I've been here for a little over three years myself.
It's a functional medicine company that started in cancer cell testing, and we have expanded our platform and technology into what we're going to introduce today. Rob's going to go through the science, the assay, and a lot of those descriptions.
At the end, I'm going to close with just a couple of quick slides, outlining some potential utility applications for where the test is at this time, and what drugs we offer, how a patient or a provider could gain access to the test, and just the logistics of all of that will look like. Rob Kimmerling 3:25 As Dennis mentioned, I'm one of the co-founders and the CTO of Travera.
My background is pretty heavily focused in assay development, single cell assay development, especially for cancer. A lot of the work we've been doing at Travera has focused on exactly that.
Want to learn more about your specific case?
Upload your medical records and ask Navis questions tailored to your diagnosis.