Ember burns bright for Angle
A clinical hit could allow the group’s liquid biopsy to expand from breast cancer to ovarian.
With approval for breast cancer under its belt, Angle is turning its efforts towards ovarian cancer – and data on Parsortix, its unusual approach to the liquid biopsy concept, suggest it may have a chance of expanding into this new setting.
But the setting is a fairly small one – not in the same league as those for the multi-cancer screens such as Grail’s Galleri, for instance – and sales are not expected to be huge. Perhaps this is why Angle’s shares climbed just 1% on the news, although now is not a great time to have a London listing.
In the Ember trial, Parsortix was used to harvest whole, living tumour cells circulating in the subjects’ blood. These were then evaluated using Angle’s Landscape+ Ovarian assay to predict the risk of malignancy, in concert with the physician’s initial cancer risk assessment and the patient’s age. The subjects then underwent surgical tissue biopsy to provide a definitive diagnosis.
This method beat doctors’ initial assessment alone, with what Angle calls best-in-class sensitivity and specificity. Berenberg analysts wrote that the data compared “very favourably” to Angle’s peers, which it said had tests averaging 90-95% sensitivity but only 50-80% specificity.
A glance at prior readouts on other liquid biopsies suggests that Exact Sciences might in fact have a better test than Angle’s, though it should be stressed that the cross-trial table below is a very rough guide.
|Data on selected liquid biopsies in ovarian cancer|
|Company||Angle||Grail (Illumina)||Exact Sciences|
|Product||Parsortix||Control arm*||Galleri||MCED test|
|Study||Ember||CCGA (2019 Asco cut)||NCT03662204 (2020 cut)|
|*Control was physician's initial cancer risk assessment. **Sensitivity at prespecified 99% specificity. PPV & NPV = positive and negative predictive value. Source: Company communications.|
There are important differences that should be noted when comparing the trials in the above table. Firstly, Ember was specifically focused on ovarian cancer, enrolling patients with pelvic masses to detect which were malignant. The CCGA study of Galleri recruited people with and without a definitive diagnosis of any cancer, and Exact’s study enrolled subjects who had been diagnosed with any solid tumour, or who had a suspicion of diagnosis based on imaging.
Secondly, the data on Exact’s assay came from a combination of the training and validation sets of a subset of patients in its study. The Grail data were also a sub-cut of a much larger trial.
Still, the Angle data look promising enough that the company is “finalising detailed plans” for selling the Landscape+ Ovarian assay, presumably as a lab-developed test. But the product might not make earth-shattering amounts of money. Berenberg sees Angle making ovarian cancer testing sales of just £14m ($15.2m) in 2026, compared with £29m in breast cancer.