FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 1

FDA Virtual Townhall

Moderator: Ivory Howard

May 5, 2021

12:15 pm ET

Coordinator: Welcome and thank you for standing by. At this time all participants are on 

listen-only mode until the question-and-answer session. At that time if you 

would like to ask a question over the phone please press star then 1. Today's 

conference is being recorded. If you have any objections you may disconnect 

at this time. And now I would like to turn the meeting over to Ms. Ivory 

Howard. You may begin. 

Ivory Howard: Thank you. Hello. I'm Ivory Howard of CDRH's Office of Communication 

and Education. Welcome to the FDA's 54th webinar in a series of virtual 

town hall meetings to answer technical questions about the development and 

validation of tests for COVID-19. 

Today Dr. Timothy Stenzel, Director of the Office of In Vitro Diagnostics and 

Radiological Health in the Office of Product Evaluation and Quality and Toby 

Lowe, Associate Director for Regulatory Programs, will provide a brief 

update. 

Following opening remarks, we will open the line for your questions. Please 

remember that during this town hall we are not able to respond to questions 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 2

about specific submissions that might be under review. Now please welcome 

Dr. Timothy Stenzel.

Dr. Timothy Stenzel: Welcome again to this week's call. We look forward to engaging you. 

We did receive some prior questions which Toby will go through first. There 

aren't that many so we'll go through all of them first and then go to live 

questions. 

I did want to make one comment and that is we still recommend that any 

molecular comparator for any submission be of high sensitivity with an 

extraction step and that it be EUA authorized as used in the developer's, in the 

sponsor study. 

If it is not EUA authorized or if there is an alteration to the authorized method 

it will cause a significant delay in our review because then we'll be required to 

bring in a molecular review group to look at the method that you use. 

So if you want to streamline your submission we recommend you use an EUA 

authorized test. We also recommend that you check with us first to make sure 

it's an appropriate molecular comparator. And if there is some requirement by 

what - for whatever reason for your product, to make an alteration to an EUA 

authorized product or not use an EUA authorized product, we do recommend 

you reach out to the FDA and explain that and let’s have a discussion, to make 

sure that, you know, that is the most efficient and best way to go forward. 

So yes, that's just going to help you, the developer group, to have an efficient 

review by our teams. And we have seen issues come up. We've seen issues 

come up that - aware that sponsors did not do this and in both different cases, 

and it has caused significant delays in the review and so we recommend we 

together, try to avoid that. Okay. Thanks. Over to Toby. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 3

Toby Lowe: Thanks Tim. Thanks everyone for joining us again this week. I'll go through 

the questions that we received through the mailbox prior to today's call. So 

the first one is about validating changes in the volume of collection media, 

specifically they're noting that they've validated their assays for specific 

volumes and are considering increasing or decreasing the volume of collection 

media. 

And since the LOD is defined in terms of concentration it doesn't reflect the 

change of sensitivity of the assay when changing the volume. So we do 

recommend that you validate your test with the transport media identified in 

your intended use. 

Media is provided in a range of volumes and you should specify in your LOD 

testing what volume you tested and note that that's the average or expected fill 

volume in the VTM provided by the vendor. If you're trying to change the 

transport media or the volume for your test, we would recommend performing 

a matrix equivalency study to evaluate the LOD.

And you can start with a swab spiked with known concentrations placed in 

different volumes of the same collection medium and follow the testing 

instructions for your test. That should take into account the dilution factor 

there. You can also, if your test uses an appropriate extraction step, you could 

perform a clinical evaluation with samples collected in a larger volume to test 

the worst case scenario. 

The next question that we have is asking about pre-submissions for nonCOVID projects. As we've discussed previously, the volume of submissions 

for COVID tests has impacted our non-COVID work. And we did put out 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 4

some information, I believe it was last week, about - through a Voices blog 

about that workload. 

And we, generally unless an IVD pre-submission is related to COVID-19 

companion diagnostics, a breakthrough designation request, or has a 

significant public health impact, we have been unable to review them and we 

are using all of the tools at our disposal and we expect at this point, for the 

remainder of this year, to be declining IVD pre-submission requests that don't 

fall into those categories. 

The next question is about a serology assay developer for looking to seek 

FDA clearance rather than an EUA and asking whether that would be through 

a de novo or a 510k. Since we have not yet authorized a serology assay for 

SARS-CoV-2 outside of the EUA provisions, we would expect that the first 

submission would be a de novo request. After we get the first one and are 

able to classify them through the de novo process, so subsequent tests would 

be able to come through the 510k pathway. 

Our next question is about the use of serology tests after vaccination. And 

related to comments that Tim has made in previous town halls about, you 

know, certain tests coming back negative because they don't detect the 

antibodies that are created by the vaccine. 

And so this is asking whether FDA's position is that site S1 antigen-based 

serology tests are the most appropriate serology tests if a clinician decides to 

look for immune response from the current vaccines. So we generally don't 

have formal guidance on this topic. We can, you know, point out that the 

antibody testing guidelines from the CDC states that antibody testing is not 

currently recommended to assess for immunity to COVID-19 following 

COVID-19 vaccination. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 5

We don't yet know whether the cutoff for available serology tests would be 

the same as a protective antibody concentration threshold. That has not yet 

been established for SARS-CoV-2. And further studies would be needed to 

establish a relationship between the detection or measure of antibodies and 

protection from infection. 

So that continues to be a topic of conversation as more scientific and clinical 

information becomes available. 

Dr. Timothy Stenzel: Thank you Toby. Yes. This is definitely a very active area of review for 

the FDA. We simply don't have the data and we've checked with our federal 

government partners to support such immunity claims at this moment. As we 

have authorized for non-COVID, for certain non-COVID infections where 

monitoring antibodies and antibody levels have been authorized. 

So there certainly isn't necessarily any prohibition about moving in this area. 

We simply wait enough data to understand. It's quite likely that a quantitative 

test is - a truly quantitative test may be the best answer ultimately, as we haveas those have been primarily if not exclusively, the ones that we've authorized 

for other amenable infections and the vaccinations for them. 

Okay Toby. Back over to you. 

Toby Lowe: Thanks Tim. Our next question is about multi-analyte panels and noting that 

there is a discussion for a multi-analyte panel in the main molecular diagnostic 

template but not in the non-laboratory template for tests for home use. And 

the question is asking whether FDA would consider a home use multi-test

SARS-CoV-2 and influenza test to be eligible for EUA consideration. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 6

The sort of overarching answer is yes, the templates are not necessarily meant 

to be exclusive. There are definitely cases where some of the templates 

include some crossover where, you know, we would expect you to consider 

whether certain parts of different templates might be applicable for your 

situation and use the parts that are relevant there. 

So generally, we are open to multiplexing flu and SARS-CoV-2 in a 

prescription home use test. At this point we're not prepared to comment on 

multiplexing SARS-CoV-2 with other respiratory viruses but we are open to 

receiving submissions that propose that approach and having those 

discussions. 

We would, you know, we would suggest that you take a look at those 

templates and complete them as much as possible. And, you know, with 

taking the parts that apply and submit as a pre-EUA for further discussion. 

We would note that any multiplexed test should be simple and easy to 

interpret. 

And as a general recommendation we suggest that the results not be 

interpreted via a visual read but rather that a reader or a device to facilitate the 

correct display and interpretation of the results, is used for assays that have 

more than one analyte. 

All right. Our next question is asking about the supplemental template for 

developers of molecular and antigen diagnostic COVID-19 tests for screening 

with serial testing that we issued back in March I believe, specifically asking 

about if a new, not previously authorized at home, over the counter test, could 

be authorized for screening with serial testing based on studies testing only 

symptomatic individuals as long as there's a post authorization commitment to 

provide data from testing asymptomatic individuals. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 7

Yes. The answer yes. That is the - the intent of that template is to leverage 

the strong performance in symptomatic individuals to authorize for 

asymptomatic screening. So if all of the other requirements or 

recommendations are met including especially for at home, over the counter, 

including, you know, simple to use, appropriate lay labeling and validation 

with lay users, we would consider that, you know, that asymptomatic 

screening claim with a post authorization, condition of authorization in the 

letter of authorization, for the developer to conduct a study to establish 

performance with asymptomatic individuals. 

Our next question is about a prospective clinical study supporting 510k 

submission of a SARS-CoV-2, influenza, and RSV multi-analyte molecular 

RTPCR test, asking whether FDA has any expectation on the percentage of 

specimens tested fresh versus frozen. And if using frozen specimens asking 

about fresh versus frozen and frozen stability studies, asking about the 

requirements for that - for frozen specimen stability. 

So to support a 510k we would recommend that your prospective clinical 

study not exceed 50% frozen prospective specimens. We typically 

recommend that sponsors retest any frozen specimens with the comparator 

method prior to testing with the candidate method. And a fresh versus frozen 

study would establish that the test has similar performance with both sample 

types. 

And we've mentioned previously in these town halls as well, that if you're 

intending to pursue a 510k pathway we recommend that you submit a presubmission to discuss your clinical validation for review. 

Dr. Timothy Stenzel: Thank you Toby for your comments. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 8

Toby Lowe: Great. And our last question on the ones that were sent in ahead of time, is 

about at home over the counter lateral flow neutralizing antibody assay using 

finger stick, asking about a clarification for the study design for clinical 

agreement and matrix equivalency studies. 

Whether the clinical agreement for the clinical agreement study protocol, 

asking whether they need to run both serum obtained from vena-puncture 

whole blood as well as finger prick whole blood against the gold standard 

comparator guarantee. 

So first, we would note that we would watch out further discussions about this 

home use test and particularly whether prescription home use or over the 

counter home use would be appropriate. So we would recommend you 

coming in to talk about that with us. 

For the clinical agreement study we would recommend that you evaluate, 

excuse me, finger stick samples in a clinical agreement study and that you 

collect paired venipuncture samples from subjects so that you're able to run 

the neutralization comparator method. 

Finger stick whole blood claims should be evaluated in the clinical agreement 

and not in a matrix equivalency study. And that is consistent with the 

recommendations in the serology template regarding finger stick evaluations. 

Dr. Timothy Stenzel: Thank you Toby. I think that's the last submitted question. Correct? 

Toby Lowe: Yes. Yes, it is. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 9

Dr. Timothy Stenzel: Okay. And so I think we can go open up the line and take live questions. 

Thank you Toby. Well done. 

Coordinator: As a reminder, if you would like to ask a question over the phone, please press 

star then 1, record your name clearly when prompted. Be sure that your phone 

is not muted when you're recording your name. And our first question comes 

from (Richard Mantegna). Your line is now open. 

(Richard Mantegna): Yes. Thank you. This is (Richard Mantegna) from (Reanix). Like I'm 

sure all of the other authorized manufacturers we've been continually 

monitoring these areas of emerging variants. Initially we were using in silica 

analysis to establish whether our tests would, you know, pick up these 

variants. 

And recently, we've managed to get our hands on some actual variants that we 

could do wet lab testing. So based on that I have two questions. The first one 

is and I'm sure everyone else is getting these same questions from their 

customers, as to how our tests would stack up against these emerging variants. 

Assuming we were able to provide to FDA in the form of an amendment to 

our EUA, the data that we've accumulated would FDA permit labeling 

changes to allow us to make those claims? And a second related question is 

has FDA considered or would FDA consider providing a blinded panel of 

samples that would contain the various variants of concern at various titers so 

that, you know, people could compare head to head in a very unbiased head to 

head manner, the relative performance of these various tests? Thanks. 

Dr. Timothy Stenzel: Thank you, (Richard). Interesting question. I think we'll take that back 

for dialog within the FDA. We're not - unfortunately we're still staying 

incredibly busy and we're not looking for additional work to do. On the other 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 10

hand, variants indications are extremely important. We have been updating 

labeling when there is a potential issue. And if there's data around a potential 

issue just the magnitude of that. 

And we've got guidance out there. we've also got a new Web site. You know, 

and our pledge to the community is that as soon as we know something that 

could be an issue of significance in the United States, we will reach out to the 

developer or developers and assess that. 

And we're also looking at - ahead to variants that are either extremely low 

volume in the US or are not here yet but are present in other countries. So we 

are looking at - in the important variants in other countries that may in fact 

spread to the US and become dominant enough to affect test performance if 

there's an issue. 

You know, I understand your desire here. You know, probably and I'm not -

this is not a definitive answer but probably, we'll want to restrict our activities 

to addressing potential issues with specific tests. And, you know, part of this 

is we don't want to make work for developers either. You know? And we 

certainly remain swamped with work at the FDA; by not just COVID related 

work but non-COVID work as well. 

So hopefully your understanding of the potential, you know, response here 

that may come next week on this town hall to your question. 

(Richard Mantegna): Well thank you very much. I appreciate it. 

Coordinator: Thank you. And our next question comes from (Elizabeth Brunelli). Your 

line is now open. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 11

(Elizabeth Brunelli): Hi. This is (Elizabeth Brunelli) from (unintelligible) Diagnostics. For the 

purpose - and this is a three part question. So for the purposes of home 

collection kit EUA request, we notice that the template includes entries for 

both a proprietary and established name. What is the difference between the 

two? 

Dr. Timothy Stenzel: Toby, do you think you can respond to this question? 

Toby Lowe: Yes. I'll pull up the template right now, to see. I think that is, you know, 

generally referring to if you have a specific name for your device and there is 

also a more generic name for it. But why don't you go ahead with your - the 

rest of your question and I'll pull that up and take a look? 

(Elizabeth Brunelli): Okay. This is just really quick on those - on the oral swabs that are used 

in the home collection kit. Does the brand of oral swab need to be specified at 

this point? And if so, is FDA registration of the swab necessary for each type 

of swab you might use? 

Dr. Timothy Stenzel: I'm thinking Toby might be answering that. Can you repeat that question? 

Sorry. 

(Elizabeth Brunelli): Does the brand of oral swab need to be specified on a home collection kit 

EUA request? And if so, is FDA registration of the swab necessary or 

required? 

Dr. Timothy Stenzel: It's preferred that it be registered. If it's not, I would have a dialog with 

our staff. And if - and in the submission I would state all the details of the 

swab used in the study. Now when it comes down to it, if there are a need for 

a developer pre-authorization, to switch swabs, we'd want to know about it in 

our review. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 12

But also post authorization in order to keep supplies on market, we're going 

to, you know, expect that if it's otherwise the same exact swab, i.e. the same 

material, the same type of swab, that that validation can be done internal to the 

developer. And as long as everything looks good it does not require a review 

by the FDA. 

And I'm not sure if Toby...

(Elizabeth Brunelli): Okay. 

Dr. Timothy Stenzel: ...has gone to the template and been able to address your question yet. 

Toby?

(Elizabeth Brunelli): Okay. So what I'm getting from that is that initially on the EUA we 

should use the FDA registration for the original swab. If we need to substitute 

that then we can do probably a validation in house for the new swab as long as 

it's the same material. Correct? 

Dr. Timothy Stenzel: Yes. Yes. And at this point, we're not hearing about wide scale swab 

shortages so we - again, we would prefer you using an FDA registered swab. 

If you're not I think that's the time. If you need to switch to something that's 

not FDA-registered due to supply issues, I would request that you reach out 

to the FDA and get some input on that before you do the work. 

(Elizabeth Brunelli): Okay. 

((Crosstalk))
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 13

Dr. Timothy Stenzel: Perhaps we can, you know, find an alternative source that's FDA 

registered for you. Go ahead Toby. 

(Elizabeth Brunelli): Okay.

Toby Lowe: Yes. I think, you know, we also - since the home collection kit is something 

that you will be distributing, we would want to know specifically what the 

components are in there. And so we would want to see, you know, we would 

want to know the brand of the swab and, you know, especially if it's not 

something that you intend to manufacture yourself we would want to know -

to make sure that it is a listed, registered and listed device so that, you know, 

if there was a recall or anything we'd know who's responsible for that. 

(Elizabeth Brunelli): Okay. 

Toby Lowe: And for the question about the proprietary name versus the established name, 

you know, I can try and get some more information for that to get back to you 

on it. But I believe that it's referring to the legal name of the device. The, you 

know, proprietary name from your company and the established name would 

be, you know, sort of if there's a more generic common name that you use for 

the device. 

(Elizabeth Brunelli): Okay. And if you don't have one you don't need to include it? 

Toby Lowe: Yes. You can use the same thing in both fields.

(Elizabeth Brunelli): Okay. 

Toby Lowe: If that's the situation for your test, for your device. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 14

(Elizabeth Brunelli): Okay. 

Toby Lowe: Yes. 

(Elizabeth Brunelli): And the last part is in the non-prescription home collection molecular PCR 

model combination, can two separate EUA request documents be submitted at 

once or do they need to be combined into a single document? 

Toby Lowe: sorry? Can you say that again? For what type of...

Dr. Timothy Stenzel: Yes? 

Toby Lowe: ...device? 

Dr. Timothy Stenzel: Yes. I didn't catch it either. 

(Elizabeth Brunelli): Non-prescription home collection combined with molecular PCR at the 

laboratory. There are obviously two separate EUA requests. Can those be set, 

like submitted together in one email or do they need to be combined into a 

single document? 

Toby Lowe: So it can - they can be separate or together in terms of a single EUA versus 

two EUA requests, depending on your situation. So if you have a home 

collection kit that you intend to only use with one single assay and they're 

both under the same EUA sponsor, you can submit that as a single EUA 

request for the system as a whole, the home collection plus the assay. 

If you instead intend for the home collection kit to be used with multiple 

assays and/or you intend for the assay to be able to use multiple home 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 15

collection kits, then we would want to see two EUA requests so that they can 

be labeled appropriately. 

And in that case you could submit them in one email or two, although it is 

probably a little bit cleaner if you submit them in two emails. 

Dr. Timothy Stenzel: Yes. And if it's different developers for the collection kit and the central 

lab test then it will be two EUAs or two amendments and it's probably best to 

keep them separate so, you know, so we can clearly delineate each submission 

in our record keeping. 

And we're going to need to move onto the next caller. Thank you. 

Coordinator: And as a reminder, if you would like to ask a question over the phone, please 

press star 1 and please limit all of your comments to one comment and 

question per caller. One moment as we wait for the next question. 

Dr. Timothy Stenzel: You may be muted. 

Coordinator: And one moment for our next question. Okay. And our next question comes 

from (Arianne Erickson). Your line is now open. 

(Arianne Erickson): Hello. This is (Arianne Erickson). I'm from (unintelligible). So I have a 

question regarding our point of care antigen IVD. So for the evaluation for 

EUA submission for point of care antigen IVD, can all aspects of patient 

endpoints and operation for our investigational device be conducted by the 

typical point of care personnel? So this would be nonlaboratory personnel and 

medical personnel. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 16

But we would like to connect this study on a CLIA site, but in a separate 

demarcated area where our personnel would have no contact with the 

laboratory personnel. 

Dr. Timothy Stenzel: You were breaking up a little bit at least for me. You have a point of care 

antigen test that you want to evaluate. And typically, we recommend - we do 

recommend that it be performed in actual CLIA-waived settings in the US 

with typically, you know, non-laboratorians actually. These are healthcare 

workers but not trained laboratorians, in order to evaluate the performance.

But there as a twist I think you introduced and I - and it - you were breaking 

up so I didn't understand the twist. 

(Arianne Erickson): Sorry. I apologize. Can you hear me now? 

Dr. Timothy Stenzel: Yes. 

(Arianne Erickson): Perfect. So we're looking to do the testing in basically a simulated point 

of care environment. This would be because sites where they're running PCR 

is a CLIA site and we would like to do it in a similar location for sample 

collection, for ease of sample collection for our operators.

Dr. Timothy Stenzel: We continue to recommend that you use typical point of care sites. You 

can also use - there's a whole lot more CLIA-waived certificate labs out there 

including at schools and workplaces. The reason to recommend that these 

types of settings be used is if they're doing this kind of work, you know, 

they're a busy situation and they're running a lot - they're doing lots of things 

all at once. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 17

In a typical point of care clinic they're seeing patients for a lot of other issues 

other than COVID. And they then intersperse work for you or a point of care 

device if it's already authorized, in all their other work. So we want to see in a 

busy clinic situation for example, that they still can follow the directions. It's 

robust enough that they can get the accurate results. 

So simulated situations for point of care are not something that we would 

recommend. And if you absolutely have to go that route and I can't dissuade 

you on this call, then I recommend you reach out to our FDA staff and discuss 

this with us. 

We are allowing simulated home environments. That's a different situation. 

Because a home user isn't - they're dedicating their attention to running this 

test. And rather than require developers to use it in home now we're making it 

easier to get access to home testing. 

We're bringing those home users into a simulated home environment but they 

get no assistance. You know? They're handed the kit and that's it. There's 

not training or anything. So I hope I addressed your question. 

Coordinator: And our next question comes from (Laura D'Angelo). Your line is now open. 

(Laura D'Angelo):Great. Thank you. Hi Tim and Toby. I was hoping to follow up on 

something that we talked about briefly last week, which is difficulty accessing 

VSL-3 sites. And I think Dr. Stenzel, you mentioned that there are some like 

workarounds and I did not write them down. So could you just briefly go over 

those again, quickly? 

Dr. Timothy Stenzel: Yes. And I just want to remind everybody that the transcripts from these 

calls are posted. Toby, do you know if the transcript from last week has 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 18

already been posted? So I'm not sure if I'm going to go through all of this 

quickly. But I'll just go through it quickly because there may be new callers

on the line today. But yes, we do not require VSL-3 facilities for any type of 

validation. 

It's only if a developer wants to use live virus that they would have to do that. 

But there are inactivated viruses. There are heat inactivated, there's - and

these are for analytical studies, not for clinical studies. Heat inactivated or 

radiated virus that can be obtained from VEI and potentially other sources. 

And then actual patient, residual patients samples can be used. And for 

analytical studies sometimes you can dilute that down in negative patient 

matrix to an appropriate level for the given analytical study. So again, VSL-3 

level labs are not required to be used by the FDA for any test validation. 

And it's only the developer at this point who may want to use a live virus that 

would do that, but that would be in their own court or anything that's specific 

for their device that requires that. And then please do check my comments on 

the transcripts that are posted for last week. Thank you. 

(Laura D'Angelo):Thank you. 

Toby Lowe: And just to clarify, last week I don't believe it's posted yet. But it will - it 

should be posted very shortly. 

Coordinator: All right. And the next question I believe the caller's name is (Whitney Dell). 

Your line is now open. 

(Whitney Dell): Hello? Did you say me? 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 19

Dr. Timothy Stenzel: Hello? 

Coordinator: Your line is open. 

(Whitney Dell): Hello. Is that for me? (Whitney Dell)? 

Dr. Timothy Stenzel: We can hear you. Go ahead. 

(Whitney Dell): Yes. Okay. Yes, I have a question regarding the home collection kit for 

multiple molecular assay. So must all the assays be EUA? Can the home 

collection kit be used for LDT as long as it has the RP in there? 

Toby Lowe: So tests that are used for home collection do need to be authorized. So we 

would expect that the - both the assay and the home collection kit be 

authorized and be authorized specifically for that indication. 

(Whitney Dell): I see. So they have to - okay, so okay, useful for LDT how is it going to - if 

we want to use the authorized home collection without LDT assay, how 

should we follow or should we follow the CLIA, CLIA regulation at CMS? 

Or we cannot even do that? 

Toby Lowe: I’m not quite sure I’m following. The test needs - would need to be 

authorized through an EUA so we would expect an EUA request to be 

submitted to FDA. 

Dr. Timothy Stenzel: If there are kit developers out there who are thinking about, you know, 

having a lab use it as an LDT but they've provided a kit with complete 

instructions and it's built for use for clinical purposes, that would not be a 

good thing to do. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 20

I, you know, and we don't recommend that. And if we do find a kit 

manufacturer who's doing that it would be important for us to reach out to 

them and at least have a discussion about what's going on. So, and that's 

intended for - anything intended for clinical purposes. So it's not a 

recommended way to get into the United States. 

Toby Lowe: Right. And to clarify, a test that is intended to be used at a clinical lab, a test 

kit that is intended to be used at a clinical lab for clinical testing, does not 

meet the definition of RUO or research use only. So the, you know, there 

should not be RUO test kits being sent to clinical labs for clinical testing, you 

know, to be "called an LDT."

Dr. Timothy Stenzel: Yes. And I'll just say I found another warning letter yesterday about the 

marketing of an unauthorized test in the United States, so - kit. So this is, you 

know, something that the FDA takes a serious look at. All right. if there is 

another caller we'll take that call. 

Coordinator: And as a reminder, to ask a question over the phone, please press star 1. Our 

next question comes from (Anna Powell). Your line is now open. 

(Anna Powell): Hi. This is (Anna Powell). I have a question regarding rapid antigen POC 

EUA definition. So far we have conducted a clinical study with prospective 

samples. We have very good performance but only have 22 symptomatic and 

ten asymptomatic. Now we know that the EUA submission requires the 30 

positives and more. I'm talking about positive sample here. 

Would ten asymptomatic be sufficient to make the total number more than 30? 

Or you need us to obtain additional symptomatic positive sample? 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 21

Dr. Timothy Stenzel: That's an interesting question. I think typically we want to see a full set of 

symptomatic samples so that we can see. Is this a molecular test or an antigen 

test? 

Coordinator: Her line was removed. Please press star 1 again and I'll reopen your line. 

Toby Lowe: It was antigen Tim. She said it was a rapid antigen point of care. 

Dr. Timothy Stenzel: Yes. The challenge with an antigen test is we really do want to record the 

days since symptom onset. So we know how many days that a test is going to 

be performing well. And so purchasers and users of that test know the 

window after symptoms for symptomatic patients in which the test performs. 

So if you include a non-symptomatic patient who legitimately can be COVID 

positive we're not going to collect that information. And with only 20 or 22 

cases our confidence interval of around the sensitivity and the days after 

symptom onset that it is sensitive enough for authorization, are more limited. 

So fortunately, you know, it is easier to enroll symptomatic patients in clinical 

studies and identify them and get them - and get positives that way, than it is 

asymptomatic. 

The fact that you have ten asymptomatics and perhaps performance is good in 

them, is encouraging because it means that once you get those additional 

symptomatic subjects enrolled and your performance remains good in the 

symptomatic population, when you submit the data all looks good, you have 

the opportunity if you wish, to apply not only for symptomatic claims but also 

asymptomatic screening. 

Coordinator: Thank you. And our next question comes from Alexis Sauer-Budge. Your 

line is now open. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 22

Alexis Sauer-Budge: Hi. This is Alexis Sauer-Budge from Exponent. I had a question with 

regards to a study design for a breath analyzer which is based on antigen 

detection. Would an appropriate comparator still be recommended as a high 

sensitivity molecular test or should we also consider antigen tests as a 

comparator?

Dr. Timothy Stenzel: Antigens are typically not a good comparator because they're not as 

sensitive as high sensitivity molecular central lab tests with an extraction step. 

You have a breath test that looks for antigens? 

Alexis Sauer-Budge: That's right. Yes. 

Dr. Timothy Stenzel: Okay. Well the comparator would still be at least a - actually I don't know 

what a true comparator is here but what swab type it is. But if you email our 

template email address we can give you some feedback for a breath test 

recommendation. We're still working on a template for these sorts of tests and 

we'll post them as soon as we can. But we can provide some feedback now if 

you email our Templates email address.

Alexis Sauer-Budge: Yes, thanks. We actually already did that and we're working on a preEUA submission to have a further discussion. But I just wanted to get some 

early feedback. Thank you very much. 

Coordinator: Thank you. As a reminder, to ask a question please press star 1. Our next 

question comes from (Albia Lane). Your line is now open. 

(Albia Lane): Hi. My name is (Albia Lane). And I have a question about the clinical 

evaluation study for a molecular test we're developing. So it's been really 

difficult to recruit positive - COVID positive patients and we're just 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 23

wondering what if we have some intended users run the tests on COVID 

positive saliva samples collected elsewhere? 

Is that a, you know, okay study design given the limitations these days? And 

if that's okay, you know, would you prefer to have let's say 30 intended users 

perform a test on each of the saliva samples we have collected elsewhere? Or 

would they be okay to have let's say five intended users to perform all 30 of 

these tests on the saliva samples we have so far? 

Toby Lowe: Tim, are you taking this one? You might be on mute if you're talking. 

Dr. Timothy Stenzel: I was. I was talking away. I have some of the best conversations with 

myself that way. So molecular tests targeting the detection of virus in saliva, 

is this a point of care test? 

(Albia Lane): It's going to be a take home test that's going to be over the counter use. 

Dr. Timothy Stenzel: Okay. So I recommend you come in with a pre-sub, pre-EUA requesting 

this. That's going to be really, really challenging for a new test that hasn't 

even received authorizations say for a point of care or for a central lab 

environment. 

If you have a central lab test, moderate or high complexity, you can use 

banked samples for a molecular test. But they do need, or matched banked 

saliva samples that you need a matched NP swab for that sample. And you do 

need to also have some fresh samples, fresh positives. 

This is going to be extremely challenging. We understand that viral positivity 

rates in the United States fortunately are going down. Hopefully they stay 

down. And that there's a challenge for new test developers coming into the 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 24

market now. And especially challenging subtype, substrates like saliva to get 

positives. 

So, you know, I don't think our recommendations for validation are going to 

change yet, at this time. But do reach out to our staff, to the Templates email 

address or primarily I think through a pre-EUA. And if you want to suggest 

alternatives we will review them. 

(Albia Lane): Okay. Thank you so much. Can I ask one additional question, or does 

everyone only get to ask one? 

Dr. Timothy Stenzel: Well go ahead. Hopefully it's quick. 

(Albia Lane): Right. So this is - so that was about clinical evaluation so this is about 

usability. Do we - does FDA require or recommend us to have the usability 

study conducted on positive patients as well? So it's not really clear from the 

template. 

Dr. Timothy Stenzel: Yes. So usability study is more making sure that home users in this case, 

can follow the directions and perform the test accurately. So we have 

potential alternatives there to actually having positive patients. So again, I 

would propose something in a pre-EUA and send it to our team. 

(Albia Lane): All right. Thank you so much. 

Coordinator: As a reminder, to ask a question please press star 1. One moment as we wait 

for any additional questions. I'm not showing any additional questions at this 

time. 
FDA Virtual Townhall

Moderator: Ivory Howard

05-05-21/12:15 pm

Confirmation # 2107197

Page 25

Dr. Timothy Stenzel: We can hold on for a minute or two to see if there's anybody else that 

wants to ask a question. If not, we can close the call. 

Coordinator: Absolutely. As a reminder, to ask a question please press star 1. One moment 

as we wait for any additional questions. 

Dr. Timothy Stenzel: Okay. I don't think we're going to get any other questions. So we can turn 

it back over to Ivory, to close out. Hello, Ivory? 

Ivory Howard: Okay. I'm here. Thank you. This is Ivory Howard. We appreciate your 

participation and thoughtful questions during today's town hall. Today's 

presentation and transcript will be made available on the CDRH Learn Web 

page at www.FDA.gov/Training/CDRHLearn. If you have any additional 

questions about today's presentation, please email CDRH-EUATemplates@FDA.HHS.gov. 

As we continue to hold these virtual town halls, we would appreciate your 

feedback. Following the conclusion of this webinar, please complete a short, 

13 question survey about your FDA CDRH virtual town hall experience. The 

survey link can be found in the chat box or online at 

www.FDA.gov/CDRHWebinar. 

Thank you again, for participating. This concludes today's virtual town hall.

END