NEW YORK – UK molecular testing firm Diagnostics for the Real World recently developed and launched two new multiplex tests for COVID-19, influenza, and respiratory synctial virus. The company is also readying a hepatitis C assay for launch later this year and is at work on a third generation of its point-of-care, simple amplification-based assay, or SAMBA system.
DRW CEO Helen Lee said in an interview that the COVID-19 pandemic has been "transformational" for the Cambridge-based company, which in the past focused on the developing world by offering point-of-care tests for HIV in sub-Saharan Africa, for instance.
When the pandemic engulfed the UK in early 2020, though, the 19-year-old firm trained its energies on serving the domestic market by launching a point-of-care test for SARS-CoV-2, for which it obtained a CE-IVD mark in April 2020, and it subsequently engaged the US Food and Drug Administration to obtain Emergency Use Authorization, a process that is still ongoing.
"For the COVID EUA, we have almost completed our clinical trial and will be submitting to the FDA in May," said Lee.
The SAMBA II SARS-CoV-2 test supports the detection of the virus that causes COVID-19 from both nasal and throat swabs and detects the Orf1ab and N regions of SARS-CoV-2. It produces a result in less than 90 minutes. The ability to turnaround a sample in that timeframe, and at the point of care, led to uptake within the UK in emergency rooms, schools, and nursing homes, known as care homes in the UK, Lee said. Last year, the UK government's Technologies Validation Group validated the test as a Class I assay, meaning it has the highest level of performance and does not require follow-on screening or confirmatory testing.
Next out of the pipeline are its SAMBA II SARS-CoV-2/FluA/FluB nucleic acid-based amplification test for the qualitative detection of SARS-CoV-2, influenza A, and influenza B, and its SAMBA II SARS-CoV-2/RSV test for SARS-CoV-2 and respiratory syncytial virus.
DRW obtained CE-IVD marks for both assays in December 2021, a regulatory certification that is valid also in the UK through July 2023, when the country, which left the EU in 2020, completes its transition to a new regulatory regime which will require the new UKCA mark.
Lee said that DRW will eventually seek FDA clearance for the new assays too.
In March, the UK Health Security Agency (UKHSA), the executive agency of the government's Department of Health and Social Care, published technical validation reports for the SARS-CoV-2/FluA/FluB and SARS-CoV-2/RSV assays, concluding that they met the "diagnostic performance criteria for both sensitivity and specificity" and required no follow-on or confirmatory tests.
According to Lee, the technical validations were necessary to obtain a contract from the UKHSA, which has overseen pandemic response since it was established in April 2021. She said that DRW had submitted data to the agency for the technical validation in December 2021.
The UK government has been a significant customer for DRW. In May 2020, the UKHSA inked a Phase 1 contract worth more than £20 million ($25 million) with the company, followed by a £59 million Phase 2 contract in September 2020, and a Phase 3 contract worth more than £95 million in June 2021. According to Lee, the first two contracts were solely related to DRW's test for SARS-CoV-2. The most recent contract covers all three assays.
Altogether, the total contracted order value to date has been nearly £175 million. So far, the company has delivered 2.3 million COVID-19 tests to UK hospitals, and will deliver another 1.5 million tests through March 2023.
These contracts have enabled DRW to build out a sizable installed base of SAMBA II systems throughout the UK. According to information provided by DRW, there are more than 1,000 SAMBA II machines installed in National Health Service hospitals around the UK, the bulk of which are in England. "England keeps us pretty busy," remarked Lee.
The company said it has systems placed at 83 percent of UK hospitals with type 1 attendances and emergency admission departments, a class of hospital emergency care providers that offer 24-hour service. An early adopter of the system for SARS-CoV-2 testing was Cambridge-based Addenbrooke's Hospital. Addenbrooke's also helped to validate the test.
To date, DRW has launched two SAMBA systems for processing its assays. The SAMBA I consists of two instruments, SAMBAprep for sample extraction and SAMBAamp for amplification and detection. The latter instrument can run up to six samples at a time and has a throughput of about 72 samples per day. This first-generation system is now obsolete, according to the firm.
SAMBA II, its flagship system, is fully automated. It includes a tablet that controls an assay module and displays results. Originally developed for challenging environments, it works in temperatures ranging from 10 degrees C to 38 degrees C. It requires minimal training and less than a minute of hands-on time to operate. Reagents require no cold chain storage, and cartridges are sealed to prevent contamination. The system also does not produce cyanide as a by-product, meaning users do not need to dispose of the lethal gas.
The machine provides a test result for one sample in about 90 minutes and is about the size of a coffee machine.
According to Lee, DRW is currently developing a third generation of the SAMBA system, called the SAMBA III that will increase the number of targets that can be detected per sample. The turnaround time will also be reduced to about 35 to 45 minutes.
"SAMBA III retains all the advantages of SAMBA II but is faster, more multiplexed in that SAMBA II can detect up to five targets simultaneously, but SAMBA III can detect up to 15 targets simultaneously," said COO Craig Wisniewski, who added that the SAMBA III will also have an improved user interface.
According to Lee, the SAMBA III will also support two detection technologies, both PCR and the firm's simple amplification-based assay, which is based on the isothermal amplification of nucleic acids. The method is based on simplified chemistry without the need for complex instruments and can be used for the visual detection of viral nucleic acids.
"We are trying to get the best of both worlds, to be more flexible, quicker, and highly multiplexed," commented Lee.
Lee is a seasoned hand in the diagnostics space. She began her career at the Centre National de Transfusion Sanguine in France, and later worked at Abbott Laboratories in Chicago, where she helped develop a number of widely used molecular tests. She is also a former chair of the World Health Organization's diagnostic steering committee. With Wisniewski and several others, Lee cofounded DRW in 2003 as a spinout off the diagnostics development unit at the University of Cambridge "with the practical intent to make molecular tests for the developing world," she said.
The company's UK headquarters is at Chesterford Research Park, south of the university city. It employs 150 people worldwide, and maintains a US office in San Jose, California. Lee credits DRW's Cambridge links with facilitating its development. "There are so many innovative companies specializing in different parts of the [SAMBA] machine," she said. "I think that is one of the reasons we as a small company were able to grow so fast."
The company is also expanding international sales with distributors added in the Nordic countries and New Zealand. Limoni is DRW's Norwegian distributor, while Canterbury Scientific, based in Christchurch, covers the New Zealand market. Lee said that DRW recently completed validating its SARS-CoV-2 test in New Zealand and has submitted it to the country's department of health for product approval.
DRW is also now returning to developing its assay for hepatitis C. Lee said the company has resumed the clinical trial of the test, which was interrupted due to the COVID-19 pandemic.
The assay is targeted for launch in the third quarter of this year, she said.