Greetings and welcome to PDS Biotechnology Fourth Quarter 2021 Earnings Call and Webcast. At this time, all participants are in a listen-only mode. A question-and-answer session will follow the formal presentation. . As a reminder, this conference is being recorded. It's now my pleasure to turn the conference over to Gabby DeGravina. Please go ahead.

Good morning. And welcome to PDS Biotechnology's fourth quarter and full-year 2021 earnings conference call and audio webcast. With me today from the company are Dr. Frank Bedu-Addo, Chief Executive Officer, Dr. Lauren B. Wood, Chief Medical Officer, and Matt Hill, Chief Financial Officer. Earlier this morning, PDS Biotech issued a press release announcing financial results for the quarter and year ended December 31, 2021. We encourage everyone to read the press release as well as PDS Biotech's report on Form 10-K, which was filed with the SEC earlier this morning. The company's press release is available on the PDS website at pdsbiotech.com and the 10-K should be posted later today. In addition, this conference call is being webcast and will be archived on the company website for future reference. Before we begin, we need to remind everyone that, on today's call, the company will be making forward-looking statements regarding regulatory and product candidate development plans, as well as research activities. These statements are subject to risks and uncertainties that may cause actual results to differ from those forecasted. A description of these risks can be found in the PDS Biotech's most recent filings with the SEC. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this conference call. Except to the extent required by applicable law or regulation. PDSB undertakes no obligation to update the forward-looking statements included today to reflect subsequent events or circumstances. With that, I would now like to turn the call over to Dr. Frank Bedu-Addo and Lauren Wood. Frank?

Thank you, Gabby. And thanks to all of you for joining us this morning. We have undergone a period of incredible productivity and progress here at PDS Biotechnology, and I would like to share some highlights from the past year as well as our more recent progress. The National Cancer Institute, NCI, presented promising preliminary safety and efficacy data from the first 18 subjects in the triple combination trial of the American Society of Clinical Oncology, ASCO, Meeting in June of 2021. This preliminary data demonstrated the potential to provide clinical benefits and extension of life in the majority of patients with advanced HPV associated cancers who have failed all treatment options. The NCI achieved their target recruitment of 30 patients in the checkpoint inhibitor refractory arm this quarter and 45 patients in total have been enrolled to date. In Q2, Q3, we hope to have additional efficacy updates for this trial presented at a leading peer reviewed clinical conference. The PDS Biotech led VERSATILE-002 trial is evaluating PDS0101 in combination with Merck's Keytruda in recurrent or metastatic HPV positive head and neck cancer. Safety data was presented at the multidisciplinary Head and Neck Cancers Symposium in February, and successful achievement of the preliminary efficacy milestone was also reported this February. Based on the successful attainment of the preliminary efficacy milestone in checkpoint inhibitor-naïve subjects, we similarly anticipate presenting more detailed efficacy results at an upcoming peer reviewed conference in the coming months. For the MD Anderson-led trial evaluating PDS0101 in combination with chemo radiotherapy in locally advanced cervical cancer, we still remain on track to provide data late in Q2 or early Q3. This quarter, we announced the initiation of the new PDS0101 trial to be led by Mayo Clinic. This trial is studying the use of PDS0101 with…

Thanks, Frank. And thanks to all for joining us today. Our most progressed clinical program is the National Cancer Institute sponsored Phase II trial studying PDS0101 in combination with both bintrafusp alfa or bintra for short, and M9241, also known as NHS-IL12, two investigational immune-modulating candidates owned by Merck KGaA. The study is investigating the combination in patients with recurrent or metastatic HPV positive cancers, including anal, cervical, head and neck, penile, vaginal and vulvar cancers who have failed prior treatment. One cohort is evaluating patients who have not been treated with checkpoint inhibitors and have not responded to at least one standard of care therapy. These are CPI-naïve patients. Almost all patients in this cohort have failed both chemotherapy and radiation treatments and would be moving on to checkpoint inhibitor therapy as a potential treatment option. The second cohort is evaluating the triple combination as a third line treatment in patients with recurrent or metastatic HPV positive cancers who have failed checkpoint inhibitor therapy. These are the CPI refractory patients. To date, the study has recruited 45 patients. As of December 31, 2021, 30 patients who are HPV16 positive had at least one evaluation. There's currently about a 3 to 1 ratio of CPI refractory patients to CPI-naïve patients enrolled in the trial. This means that we have a significantly larger number of patients who have failed all of the treatment options being studied. As reported at ASCO in 2021 by the NCI, CPI-naïve patients historically have a median survival of 7 to 11 months on CPI monotherapy. CPI refractory patients who have failed all three treatment approaches have a historical median survival of only three to four months. As of December 31, 2021, the median overall survival of these patients on this study exceeds 12 months and counting.…

Thank you, Lauren. First, I want to thank our shareholders for your patience with the rescheduling of our earnings call. Our auditors needed more time to complete the procedures. And in order to give them that time it made sense to reschedule this call to today. With that, let's move to the financial discussion. For the year ended December 31, 2021, the net loss was approximately $16.9 million or $0.66 per basic and diluted share compared to a net loss of approximately $14.8 million or $0.89 per basic and diluted share for the year ended December 31, 2020. As of December 31, 2021, PDS Biotech had 28.4 million common shares outstanding and 31.8 million common shares outstanding on a fully diluted basis. For the year ended December 31, 2021, research and development expenses increased to approximately $11.3 million compared to approximately $7.9 million for the year ended December 31, 2020. The increase of $3.4 million was primarily attributable to an increase in regulatory and clinical costs of $2.6 million, non-cash stock-based compensation of $1.1 million, personnel costs of $0.4 million, partially offset by the overall decrease in manufacturing and facility costs of $0.7 million. For the year ended December 31, 2021, general and administrative expenses increased to approximately $10.2 million compared to approximately $7 million for the year ended December 31, 2020. The $3.2 million increase was primarily attributable to an increase in personnel costs of $1 million, non-cash stock based compensation of $2.5 million, and facility costs of $0.1 million, partially offset by a decrease in professional fees of $0.4 million. Total operating expenses for the year ended December 31, 2021 were approximately $21.4 million, an increase of approximately 44% compared to total operating expenses of approximately $14.9 million for the year ended December 31, 2020. The company's cash balance as of December 31, 2021 was $65.2 million. Based on the company's available cash resources and cash flow projections, the company believes that this balance is sufficient to fund the company operations and research and development programs through the end of 2023. With that, why don't we open it up to questions? Operator?

. Our first question today is coming from Louise Chen from Cantor Fitzgerald.

Congratulations on all the progress over the quarter. My first question for you is if you could provide more color on the new adjuvant opportunity for PDS0101. Is this part of that $5 billion to $6 billion that you mentioned earlier in the call? Or is this on top of that? And the second question I have for you is on your flu platform, impressive data. But I'm curious why you have confidence that you can move forward with your platform here, while many others have actually failed. And then, last question I had for you was if you could provide an update on your MUC-1 and TARP program.

Let's start with the Mayo program. So, if you notice, with our PDS0101 programs, PDS0101 is really designed to be a real demonstration program for the company. And you'll notice that we have started with the very late stage cancer patients who have failed all treatment options. And those are the checkpoint inhibitor refractory patients. We're also doing trials in patients who have failed other options, but not yet checkpoint inhibitors, the checkpoint inhibitor-naïve population. And then, with the cervical cancer trial led by MD Anderson, we are then looking at pre-metastatic cancer. So, locally advanced. And the Mayo trial gets us even earlier. So, the strategy here is to cover the entire breadth of indications. And also, when you look at the NCI trial, we're not only looking at a specific type of cancer, we're looking at all types of HPV associated cancers, and the early data has suggested that the biomarker approach or the molecularly targeted approach is potentially viable for this program. So, really, the strategy here with PDS0101 is to provide or obtain as much coverage in $5 billion to $6 billion US market as commercially feasible, right, to demonstrate potential superiority or to demonstrate superiority – period – if we can achieve that across the board and for this range of – broad range of HPV associated cancers. And all these things incorporated within that $5 billion to $6 billion market, right? So, that's really the strategy here, seeing very promising data with the late stage cancer programs, seeing potentially good safety, and therefore now coming earlier and earlier in the cancer stage. Moving on from there to the Infectimune program and the universal flu. So, with universal flu, the approach that has typically been taken has been to include probably two or three or…

Our next question is coming from Leland Gershell from Oppenheimer.

A couple of questions for me. First, with respect to the recent rise and incidence of HPV driven cancers, clearly, with HPV vaccines, some may expect those rates to go down, perhaps those are only active toward cervical HPV cancers and not others. Perhaps, Frank or Lauren, you could delve into that dynamic a bit more for us. And then secondly, with respect to kind of the cadence of trial data revealed, particularly with regard to the NCI triple combo trial, maybe perhaps you can share with us kind of the process in which decisions are made as to when to release data and who's really in charge of making those decisions.

I'm going to start answering, Lauren, regarding the HPV market and the HPV disease and you can jump in with any additional comments once I go through the first set of answers. But with the HPV associated disease, one of the key things is that's important in terms of the presence of these preventive vaccines out there today and what impact they could potentially have on the markets. Now, there has been a lot of epidemiology work done. And there are a number of reasons that have been presented as to why some of these incidences are still on a significant rise, an increase, for example, in head and neck cancer. And the reason for this is the current vaccines are only preventive in nature. And they're only effective if those vaccines are administered before the patient is actually infected with the virus. And as we know, the HPV is the most prevalent sexually transmitted agent worldwide today. So, it's very highly prevalent. And these vaccines are active only if they are given ahead of that infection. Secondly, these are very slowly progressing cancers. And so, sometimes it's been reported that these could take even a couple of decades from the time of infection to the time of actually getting the cancer. So, those are very important in terms of the incidences. And so, what has been projected is that based upon these critical factors, where you have the current vaccines are only effective before infection and the very high rates of infection, that very likely most of the patients we will be treating over the next 20 or so years have already been infected with the virus and people are still getting infected with this virus. And so, head and neck cancer is a really good example where the…

Our next question today is coming from Jim James from Alliance Global.

I had a question on – you're looking at the expected timing for the next – the triple combination bintra interim look there. And I want to make sure I understood the correct timing on the VERSATILE-002 combo with Keytruda for the next interim look. And then, I think you had mentioned in the past or indicated in the past that you're likely to be partnering, particularly the triple combo for Phase IIIs and launches. Can you talk a little bit about the partnering environment? And given the data is looking good, but still pretty early, how does how does the partnering environment look at this point?

In terms of the data, presenting the data, and we anticipate that this would be at a conference, either late Q2 or early Q3. And in terms of the – for the NCI trial, triple combination, we're looking at two specific groups of data in terms of the data on the patients, the patients whose data was presented at ASCO last year, how have those patients fared over that period, over the years since ASCO to date? And also, how does the new patient data looked like compared to those patients whose data was prepared for presented at ASCO? So, essentially, what is the durability of these immune responses and what's the efficacy? Is it holding up similar to what we saw at ASCO last year? And so, that we are hopeful that we will be able to present that data probably late Q2. And the same with VERSATILE-002, we provided the top line data in terms of meeting that critical milestone of how many patients for at least four or more to progress this into full enrollment. We are hopeful that we should be able to, at the conference again, either late Q2, early Q3, present more details on these results in terms of the objective response rates, the overall survival rates, progression free survival, in addition to the safety data that has already been presented to provide more in depth analysis of the data that has been generated to date. And so, the way we look at this is the PDS0101 studies, hopefully, Q2, Q3, if we're able to achieve these goals, will provide very solid proof of concept for the VERSATILE platform. And so, that's really the key goal with PDS0101. As I said, it's a demonstration program to provide us with that solid proof of concept…

Maybe a quick follow-up on the COVID program. I know that COVID has been waning in the US, particularly throughout the world. There's Ba2 variant out there. And I guess, you and I have spoken, there's no hard and fast rule that the next variant must be less deadly. This happened to have been the last couple of times. Have you seen a waning of interest in the COVID program? What are your thoughts on the fact that this is – US may be done with COVID, but COVID is certainly not done with the US?

That's a tough one. But the way things are progressing with COVID, if you listen to the experts, most of the experts believe that this is probably going to be with us for the long term and that we're probably going to have to be getting vaccinations on a regular basis. And I think the way we are looking at this is what are the opportunities today in the COVID-19 space? And very likely, we think it's a couple of things – safety, robustness and durability of the immune response, meaning can a vaccine be developed that provides long term protection, so for at least a year, and can we also induce the kinds of immune responses that provide robust protection against multiple strains of COVID-19. And based upon what the experts are projecting in terms of how long COVID is going to be here, we believe that if a vaccine can be developed that meets these characteristics, long-term protection, maybe a year or so, and also broader protection in terms of protecting against multiple strains, that there is very strong potential for that vaccine to be a commercially successful vaccine. And to be able to do that, we believe that T cell response, in addition to strong neutralizing antibodies, provide that potential to do this successfully. And so, based upon that and also based on the fact that we are really not committing any of our resources to doing that, and that's really been done by our partner in Brazil, who appear to be making some good progress – so we've been in touch with them, as we mentioned. We are going to revisit that program by the end of May. We gave them extension through end of May. And so, we will be revisiting that, looking at their progress and making a decision of that at that point, but they are making progress. We do believe that there is still a commercial opportunity for a vaccine that can be differentiated in terms of safety, durability, and breadth of response.

Our next question is coming from Joe Pantginis from H. C. Wainwright.

I wanted to focus my question more on the macro components of flu right now, but obviously with a focus on 0202 as well. So, do you feel that there can be an increased focus now or coming off a season where the current flu vaccine, really the data show that the efficacy was much lower because the predictions weren't there because flu hadn't been around? Do you feel that that can create increased focus and the desire for a universal flu vaccine even though these approaches have been around for quite some time?

Joe, you make a very good point that these approaches have been around for quite some time. So, I think for at least a decade, there has been a lot of interest in developing a universal flu vaccine. I think with what's happened with COVID-19 and the rapid mutations, I think it has brought into focus a little bit more the potential for pandemic flu, for example. Now whether there is going to be more interest dedicated to this by some of those agencies, the governmental agencies or not, that's really difficult to say. But I think based upon what we've seen, for example, our program, as we mentioned, is funded by the NIAID, we are hopeful that we will be able to get the funding to take it into human clinical trials hopefully by the end of the year or late early next year. And I think it will be important there to be able to translate the preclinical data into human data. And I think that will be very important in being able to demonstrate the potential to do this. But there has been a lot of interest just based upon the very low reported efficacy of the flu vaccine from season to season to be able to have something that's a little bit more effective and endurable. And I'll actually ask Lauren to add if there's anything Lauren wants to add to this.

I think everyone is aware of the fact that, depending on which respiratory viruses may be predominating at certain seasons, you then see impacts on other viral infections. So, during the last two years, we've had a predominance and a focus on SARS-CoV-2, and we saw lower incidences of flu and RSV. Again, as SARS-CoV-2 now starts to recede, we're starting to see flu, as well as RSV cases come up. Ultimately, people are believing that hopefully SARS-CoV-2 may become an endemic virus which is going to still have the need because of its mutability to have an effective vaccination that addresses it. We now have flu that is highly mutating and seasonal, as well as potentially ongoing, different ways of SARS-CoV-2. And because of that, I think you're actually seeing in the sector, the fact that individuals are still trying to address coming up with vaccine approaches that would be broadly reactive, universal vaccines for not only flu, but also for COVID. And you're seeing attempts at developing dual agent vaccines that would protect against both flu as well as COVID at the same time, so there is going to unquestionably be need, there is unquestionably interest. And, again, as Frank has highlighted during the call, I think what's differentiating about the Infectimune based platform with the flu, COBRA antigens from the University of Georgia that Ted Ross has developed is we not only see neutralizing antibody responses, which is the end all, be all historically of infectious disease vaccines, but we are also seeing the development of those T cell responses, which have the opportunity to provide long-term memory and potentially greater duration of protection. Right now, it's looking like everybody is going to need COVID boosters every six months. So prolonging duration of protection, so that vaccines can be delivered once a year or longer, as well as having broad protection across a range of viral strains and species is going to be very critical for both flu and for COVID.

Maybe I'll just take it one more step because of the way Frank put it, currently, the hope is in order to get it in to the clinic, or with getting it into the clinic, you would like to still have your collaboration with the NIAID. But maybe you could talk to your flexibility and/or optionality that also brings Matt into the conversation since he is controlling your guys' checking account. So, with regard to maybe looking for external funding or something like the Gates Foundation or anything along those lines, or what you might want to or not want to throw behind it with company-based funding.

I'll let Mark Masse also join in. But we have all options on the table in terms of partnering and looking at other non-dilutive options, but at the moment, we're not seeking to utilize any of our current cash in progressing that program at this point.

Yeah, absolutely. And when we look at the size of the markets currently in oncology, $5 billion to $6 billion in HPV-related cancers, over $40 million – another $100 million when you get to MUC-1 in the potential total available markets, we're focusing our dollars right now on the oncology, immunooncology market. And we're seeking non-dilutive financing to assist us with the infectious disease, which is why we went with Farmacore originally and we're working with Dr. Ross on evaluating all aspects to help us get the universal flu vaccine into the clinic as quickly as possible.

. Our next question today is coming from Robert LeBoyer from Noble Capital.

My question has to do with the universal flu vaccine. And Dr. Bedu-Addo gave a very nice description earlier in the call. I was wondering if it's appropriate to discuss the actual targets in the virus that the vaccine would be directed against, as well as if you're seeing any data that would predict the duration of this response, whether it's going to be one season, multiple seasons, or potentially many years.

I'll start and then I'll have Lauren to jump in. The way Dr. Ross has designed these computational proteins is he's looked at multiple strains of this seasonal flu as well as multiple strains of the pandemic flu strains, and so he has the number of proteins that are designed to either focus on the seasonal flu strains as well as the pandemic flu strains. And so, we have currently focused our initial studies on the seasonal flu strains, but will very likely consider moving also to the pandemic flu strains once we've demonstrated the transition of the results we have in preclinical to human clinical results. In terms of the durability of those responses, it's very difficult to predict. They have to actually be studied in humans. And that's why we aren't just to be able to get into humans and begin to understand exactly what the durability of those responses could potentially be in humans. But I think it is promising considering the fact, as Lauren said, the induction of those T cell responses and memory T cell responses are a really good indicator of the potential durability of that vaccine and the protective responses that could be generated. But I think we will have to actually study it in in a human clinical trial. Lauren, any additional comments?

The things that I would add is that regarding – in addition to the testing that ultimately needs to be done in humans, when you get to assessing the durability of the response and the breadth of the response against different flu strains, I think what Frank has previously highlighted during our call is what we have demonstrated preliminarily to date so far, by co-delivering Infectimune with Dr. Ross' broadly reactive antigens that, again, are designed to induce immune responses across a broad range of strains of flu that have been detected over the years. What appears to be differentiating is we not only see the neutralizing antibody responses that have historically been associated with all flu vaccines, but we are also seeing the induction of T cells specific responses, both CD8 and CD4 T cell responses to these flu antigens. And this ultimately may be what is differentiating about the COBRA antigens in terms of their broad reactivity, but their co-delivery with Infectimune. The preclinical animal challenge studies certainly suggest that, but, again, the definitive bar is going to be progression to testing in human clinical trials. We also are in the process of submitting a publication detailing the immune responses induced by Infectimune codelivered with the flu antigens in PDS0202 as well as with SARS-CoV-2 antigens, and that – we hope to have that in publication before the end of the year, but that is being submitted for peer review.

Thank you. We've reached the end of our question-and-answer session. I'd like to turn the floor back over to Frank for any further closing comments.

Thank you very much. Again, thank you very much for joining us today. Our goal at PDS Biotech is to be able to rapidly provide better therapeutic options to cancer patients, and to fulfill a severe unmet medical need to offer effective treatments with extended survival to advanced cancer patients. If successful, we are optimistic this could provide renewed hope to patients and the families. We look ahead to the rest of 2022 as we continue to advance our growing pipeline of promising oncology and infectious disease candidates. Thank you very much again and have a great rest of the day.

Thank you. That does conclude today's teleconference and webcast. You may disconnect your lines at this time and have a wonderful day. We thank you for your participation today.