The U.S. FDA has rewritten the emergency use authorization (EUA) for the Laboratory Corp. of America Holdings Inc. (Labcorp) COVID-19 polymerase chain reaction (PCR) test to allow for diagnostic testing of those who are asymptomatic and those who have no reason to suspect they are infected with the SARS-CoV-2 virus. The news is welcomed by advocates of reopening the economy; however, questions remain as to whether the stockpile of supplies, including reagents, is sufficient to handle the current volume of testing, let alone the presumed expansion of testing suggested by this updated EUA.
The FDA announcement was just one of several key developments in recent days, including the July 23 extension of the public health emergency signed by HHS Secretary Alex Azar. It is good for another three months and is likely to be extended yet again in October, given the difficulty experienced in corralling the pandemic.
The FDA release announcing the EUA said that the reissue of the Labcorp real-time PCR test allows for pooled sampling, a key cog in the pandemic surveillance effort. The revised indication for use also allows the test to be used in those who have no symptoms and those “who have no reason to suspect” any infection, a change backed by data supporting the test’s ability to detect the SARS-CoV-2 virus in a general asymptomatic population.
Hahn: EUA a ‘step toward’ broad screening
The agency noted that the pooled sampling indication is contingent on observation of swab sample collection. In addition, FDA Commissioner Stephen Hahn noted that the revision to the EUA “is a step toward the type of broad screening that may help enable the reopening” of schools and workplaces. Hahn also noted that pooling may speed up the return of results to those tested, and acknowledged the EUA for a test by Quest Diagnostics Inc., of Secaucus, N.J., that also provides a pooled sampling authorization. Hahn noted that the Quest EUA was an important step forward in restoring normal activity.
The Labcorp test has been authorized for use with the company’s Pixel swab kit for at-home sample collection. However, the pooled sample protocol only can be used with samples collected by health care professionals. The FDA said it will continue to work with test developers to expand access to testing.
Labcorp’s July 25 press release makes no mention of the test’s use in asymptomatic individuals. However, it does note that its matrixed pooled testing method provides the way for distinguishing between positive and negative samples by means of patterns that are detected by the company’s robotic testing platform.
Analysts credit FDA for being ‘creative and flexible’
A July 27 note from William Blair said the news regarding Labcorp was significant in two ways, the first of which was that it confirmed the FDA’s effort to be “creative and flexible” in giving tests a green light. Analysts Brian Weinstein and Andrew Brackman said the announcement regarding the pooled sampling EUA for the Quest test was the first such indication of a renewed emphasis on flexibility on the agency’s part. Brackman and Weinstein said they expect “more and more” pooled testing EUAs in the weeks ahead.
However, they also said the more important development is the shift toward the screening of asymptomatic individuals, which they reminded is a first for the FDA. They said testing limited to symptomatic individuals is tantamount to treading water but noted that several tests are being deployed on asymptomatics.
In another development related to testing, HHS announced July 26 that it and the Department of Defense have committed to investing $7.6 million in Hologic Inc., of Marlborough, Mass. The investment aims to enable Hologic to boost production of custom sample collection and processing consumables for testing, citing production of tubes, caps and multi-tube units used for samples processed on the company’s Panther and Panther Fusion testing systems.
The HHS statement predicts that the monies will boost production from 4.8 to 6.8 units per month, adding that Hologic is expected to begin delivery of the added supplies in January 2021. There are more than 1,100 Panther and Panther Fusion systems installed in the U.S. at present, each of which can process more than 1,000 tests per day.
The William Blair note said that while the HHS press release failed to explain the focus on sample collection and processing consumables, the most likely answer is that these are the areas of the company’s supply chain that are under the most pressure. The note also pointed to a July 26 tweet by former FDA Commissioner Scott Gottlieb, which said that labs are in greatest need of supplies for their higher-volume testing systems, such as the Hologic systems. Gottlieb said bypassing supplies for the slower systems for now is how labs will most quickly “get to maximum capacity.”
The Association for Molecular Pathology and the Advanced Medical Technology Association were unable to comment for this story.