More detailed data on the cancer blood test developed by Grail add to that on tissue of origin testing revealed in the abstract drop last month. Results in a subset of patients from the vast CCGA trial, presented at Asco on Friday, showed that sensitivity of detection of various cancers at a pre-set specificity of 99% varied from 86% in head and neck cancer to 59% in lung cancer – worthy of further investigation, but hardly gobsmacking. Sensitivity varied greatly depending on how advanced the cancer was: 77%, 84% and 92% of stage II, III and IV cancers were picked up, but just 34% of stage I tumours; not great news for a company that is aiming, among other things, to develop a pan-cancer screening test. Meanwhile Grail’s arch-rival Guardant Health is gearing up to go to the regulators. Its Guardant360 liquid biopsy has been on sale in the US as a lab-developed test since 2014, but the company plans to put it on a more formal footing with FDA submission expected in early 2020. If granted, approval could be a selling point in itself, but it would also allow Guardant to seek reimbursement, potentially a major sales driver.
|Sensitivity of Grail’s liquid biopsy at detecting stages I-III cancer*|
|Cancer type||N||Sensitivity (95% CI)|
|Head and neck||36||86% (71-95%)|
|Multiple myeloma||34||71% (53-85%)|
|Hormone receptor-negative breast||67||64% (52-76%)|
|*All at 99% specificity. **Excludes leukaemias, which are not staged.
Source: company communication.