AACR 2019 Roundup: Notes from a Weekend of Early Stage Cancer Results

in the pipeline. Roche presented early results at AACR from a Phase 1b study of a three-drug cocktail that includes atezolizumab, Abraxane, and Roche’s ipatasertib. The interim data showed 19 of 26 patients (73 percent) responding to the treatment. But more than half suffered serious adverse events, the most common being diarrhea and rash.

A different type of immunotherapy also showed promising signs, albeit extremely early. In a sample of nine patients, five saw their TNBC tumors disappear after treatment with the cancer-killing virus product talimogene laherparepvec (T-Vec), from Amgen (NASDAQ: [[ticker:AMGN]]), and chemotherapy. The other four saw tumors shrink but not disappear. Two patients suffered serious side effects.

A long-term study from the American Cancer Society showed that prostate cancer is on the wane in a few countries around the world—most notably the U.S.—and not growing in frequency in many others. Prostate cancer incidence was examined for 44 countries. The study also looked at the mortality rate for 71 countries. Fourteen countries showed a decrease, three an increase, and in 54 countries the rate remained stable.

SOLID CAR-T DATA

—CAR-T cell therapy, which uses a modified form of a patient’s own live immune cells, has come to market for certain types of leukemia and lymphoma. But making CAR-T work in the more common solid tumors—breast, lung, colon, and the like—requires a lot more work because of those tumors’ ability to fight back against the immune system and bounce back if they’re not totally eradicated. Any promising signals for CAR-T in solid tumors are notable. At AACR, a Phase 1 study from Baylor College of Medicine looked at 10 patients with sarcomas—rare cancers that grow in the connective tissue. Two had complete responses to an experimental CAR-T treatment that targets cells expressing the HER2 protein. Three saw their cancers kept in check, and five did not see any benefit.

Another study at Memorial Sloan Kettering Cancer Center gathered 21 patients with mesothelioma, a cancer of the lung lining, and gave them a CAR-T treatment designed to seek out cells expressing the protein mesothelin. Two had a complete response, five had a partial response, and four saw their cancers kept in check.

LIQUID BIOPSY

Guardant Health (NASDAQ: [[ticker:GH]]) is one of several companies with a blood test to help doctors prescribe drugs based on the genetic profile of a patient’s diagnosed tumor. Data at AACR showed that the test, called Guardant360, could be an alternative to tissue-based biopsy for newly diagnosed lung cancer.

Also at AACR, a smaller firm called Resolution Bio presented data that its test uncovered more “actionable” information about patient’s lung tumors than Guardant360.

So-called liquid biopsies, which genetically profile a patient’s cancer or flag its return after remission, are becoming more established by the day.  While access to the tests and understanding their results has caused concern, Medicare has begun covering their costs.

Developers like Guardant are also aiming for a bigger target: Screening tests that find cancer before a person develops symptoms. As does its well-funded rival Grail, Guardant wants eventually to deliver a screening product that only requires a blood draw. It is following a cautious roadmap, as Xconomy described when Guardant’s effort, dubbed Lunar, was unveiled three years ago.

Only recently, Guardant made Lunar available to drug companies and researchers. It’s not close to being an on-the-ground diagnostic tool. Guardant first wants to show that Lunar can characterize previously diagnosed tumors. It took a first step in that direction with a small study in colon cancer unveiled at AACR. It’s extremely early days, as Vantage pointed out. Of the 105 patients in the study, only 25 had early-stage cancer. It is those patients, ultimately, that Guardant and its rivals want to detect. The earlier a tumor is treated, the more successful the treatment could be. The trick will be to make cancer screening as accurate as possible, because screens that give false results can do far more harm than good.

Author: Ben Fidler

Ben is former Xconomy Deputy Editor, Biotechnology. He is a seasoned business journalist that comes to Xconomy after a nine-year stint at The Deal, where he covered corporate transactions in industries ranging from biotech to auto parts and gaming. Most recently, Ben was The Deal’s senior healthcare writer, focusing on acquisitions, venture financings, IPOs, partnerships and industry trends in the pharmaceutical, biotech, diagnostics and med tech spaces. Ben wrote features on creative biotech financing models, analyses of middle market and large cap buyouts, spin-offs and restructurings, and enterprise pieces on legal issues such as pay-for-delay agreements and the Affordable Care Act. Before switching to the healthcare beat, Ben was The Deal's senior bankruptcy reporter, covering the restructurings of the Texas Rangers, Phoenix Coyotes, GM, Delphi, Trump Entertainment Resorts and Blockbuster, among others. Ben has a bachelor’s degree in English from Binghamton University.