Salient Bio launched a robotics-driven PCR test for COVID-19 with 99% for use in mass testing for the virus. The company says the "fastest ever" test notifies users of test results in less than a day and is priced to be cost effective for businesses. Salient plans to expand the number of tests utilizing the modular diagnostics platform in 2021 to include a range of pathogens.

Even with vaccines on the horizon in the coming months, the London-based company expects brisk demand for its product.

“With the rollout of vaccines likely to be staggered, rapid and accurate mass testing will play a vital role in the coming months in our immediate fight against COVID,” said Salient Co-founder Miles Priestman. With nearly all of the production runs for several months already committed to the U.S. and a few other nations, the demand for testing to manage the spread of COVID-19 and enable economic functioning elsewhere in the world is likely to continue for several years. Duke University projects that adequate vaccine supplies will not be available globally until 2024, the company noted.

Despite the huge demand for testing and the cost in lives and economic impact associated with delayed results, ”existing diagnostic labs often involve error prone manual processes – there is a huge opportunity to reinvent how they operate from the ground up,” Priestman added. “Using state of the art robotics and bespoke software development we hope to do just this, bringing significant cost and operational efficiency gains to help bring diagnostic labs fully into the 21st century.”

The automation of the process has contributed to its high degree of reliability. The company reports the test has specificity of 98% and sensitivity of 100%.

Fully automated process

The platform uses five robots to fully automate the analysis process, reducing the need for human operation and significantly speeding the time to results. The second robot, for instance, performs the RNA extraction step and can conduct about 40,000 pipetting motions in each run– an impossible quantity for any person. Four of the robots perform highly precise liquid handling tasks, with two preparing plates.

Since this is an open and modular platform, as the first step in the process completes, another machine starts the second step and so on. At the same time, the first machine begins a second batch so the total system can process multiple batches at once. High quality PCR machines with high temperature modulation speeds also reduce the time needed for temperature changes to occur, further speeding the thermo cycling time. In contrast, in the usual closed process, one batch monopolizes all the machinery.

The automation enabled Salient to cut the time to results to about a third of most lab’s processing times. The company guarantees same day turnaround if samples are received by 1 pm. Despite increasing demand from companies that have used the tests during a trial period, the company has been able to maintain the turnaround time because of its very high throughput, which currently enables processing of 2,000 tests per day, though Salient told BioWorld it has “lots of operational contingency” above that.

Salient also took steps to protect its processing ability by creating a reagent agnostic system, meaning that it can easily switch to different chemicals and suppliers if a shortage develops in one. Given the scale of supply chain disruptions experienced early in the pandemic, some which continue today, the company considered this capability essential to reliably meeting the demands of its customers for testing.

Future directions

Currently, Salient processes all tests on its own equipment at its lab and is focused on providing COVID-19 testing for U.K. customers. It recognizes, however, the need for rapid, accurate, mass testing around the world for the coronavirus and other pathogens as well and the tremendous opportunity that represents.

With this commercial launch, Salient hopes to help companies with large workforces resume safe operation, such as logistics, facilities management, education and manufacturing firms.

“Without secure and regular testing, it is impossible for companies to operate at full productivity and employees to have peace of mind. That is why we’re delighted to have developed a solution that can give interaction and labor-based industries the ability to ensure a COVID-safe environment efficiently and affordably,” said Co-founder Marta Ciechonska.

By late 2021, Salient expects to offer a variety of other tests that run on its platform, starting with chlamydia and other sexually transmitted infections that do not have seasonal variation in demand. Based on client demand, the company could adapt the workflow to process a number of different types of pathogens within samples.