The World Health Organization (WHO) has just prequalified its first hepatitis C virus (HCV) rapid diagnostic test, a tool that will aid diagnosis of HCV in low- and middle-income countries and improve access to treatment.
“The fact that we now have very effective new medicines for HCV needs to be bolstered by effective and affordable diagnostics,” said Dr. Suzanne Hill, WHO director for essential medicines and health products. “This new quality-assured test is good news for the many people awaiting diagnosis and treatment.”
The newly prequalified test, SD BIOLINE HCV, by Standard Diagnostics, Inc. (South Korea), is a point-of-care diagnostic, which makes it particularly appropriate for low-resourced countries, where testing laboratories and trained personnel may be scarce. Resembling a pharmacy pregnancy test, it does not require hospital facilities or electricity and can be performed by health workers with limited training. The test gives a result within 20 minutes.
WHO acceptance of the test comes at a time when direct acting antivirals (DAAs), new and highly effective medicines for HCV, are becoming increasingly affordable and available in low- and middle-income countries.
“The majority of people with chronic hepatitis C don’t know they have the infection and miss the opportunity to be cured,” said Dr. Gottfried Hirnschall, WHO director for the Department of HIV and Global Hepatitis Program. “Making the first WHO prequalified test available in countries can greatly contribute to achieving the goal of eliminating hepatitis.”
There are only very few HCV rapid tests on the market, and they are either not quality-assured or too expensive for countries with limited resources. This means that patients may potentially be misdiagnosed – either as false positives or false negatives. The newly prequalified test is expected to be more affordable, as well as guaranteeing quality, safety and performance. Agencies that procure or purchase health products for low-resource countries, such as Médecins Sans Frontières and UNITAID, have been waiting for such a test in order to scale up diagnosis and treatment.
“One of the chief obstacles to effective testing and treatment of HCV has been a lack of suitable diagnostic tests, with the result that only a small minority of people infected with HCV are aware of their status,” said UNITAID executive director Lelio Marmora. “We are therefore greatly encouraged by the news that a WHO-prequalified rapid diagnostic test for HCV can now be made available to those most in need.”
WHO has recently released normative guidance on care and treatment of viral hepatitis. DAAs have a more than 90 percent cure rate and now provide the opportunity for addressing the HCV public health crisis. The emergence of DAAs has stimulated renewed interest in the establishment and expansion of testing services for HCV after a long period of stagnation. In addition, the new test will help key affected populations (e.g. injecting drug users), who have not been reached by existing HCV testing services that focus on blood screening.
WHO prequalification is conducted in accordance with international standards of quality, safety and performance of in vitro diagnostic medical devices. Once a product has been prequalified by WHO, it is eligible for procurement by UN agencies. Countries and non-governmental organizations also rely on the WHO list of prequalified health products to guide their purchasing and procurement practices.
The SD BIOLINE HCV is a rapid assay that detects antibodies to HCV in human serum, plasma or whole blood. The assay is used as an aid to diagnosis of HCV infection; reactive specimens require additional testing to identify current HCV infection. The test contains a pre-coated nitrocellulose membrane strip; when the serum, plasma or whole blood specimen is applied, it moves along the membrane to the test region and forms into a visible line, which indicates a reactive result. The control line should always appear if the test procedure is performed properly and the reagents in the control line are working. The test result can be read between 5 and 20 minutes; as this is a visually-read device, no instrumentation is required to interpret the test result. The product has not been validated for infants or children.