Though not ideal, a turnaround time of less than two hours, he writes, “mitigates the problem of patients not returning to the testing site for their results, and the waiting time can be used for HCV education and harm-reduction activities . . . Given the transient nature of many people living with HCV (who are often lost to follow-up), rapid testing enables immediate action while the patient is temporarily engaged in the health-care system.”

Dr. Raymond Chung, director of hepatology at Massachusetts General Hospital, Boston, noted in a phone interview that the Xpert HCV Viral Load point-of-care test doesn’t rely only on antibodies.

The sine qua non of HCV diagnosis, he said, is the detection of viremia in the form of HCV RNA, but such a point-of-care test has been lacking until now. It’s “a potentially field-ready test” and could be especially important in low- and middle-income countries.
Though refinements still needed, and it would be ideal to shave the time down, so the patient could leave with a care plan in place, Dr. Chung said, “It’s a good start.”

The study recruited participants age 18 or older and either with a history of injection drug use or recruited from the homelessness service. The final analysis population of 150 participants had a median age of 44. Most patients (130, or 87%) were male.

The sensitivity of the Xpert HCV Viral Load assay for HCV RNA detection in plasma collected by venipuncture was 100.0% and specificity was 99.1%. The assay’s sensitivity for HCV RNA detection in samples collected by finger-stick was 95.5% and specificity was 98.1%. The Abbott RealTime HCV Viral Load RNA assay was used as the gold standard against which the Xpert HCV Viral Load was compared. A modified Xpert HCV Viral Load assay is under development with a time to result of 60 minutes.

The study was funded by the National Health and Medical Research Council (Australia), Cepheid, the South Eastern Sydney Local Health District (Australia), and Merck Sharp and Dohme (Australia).

Dr. Grebely has received research grants from Cepheid; two authors are employees and have equity interests in Cepheid.