Thank you, operator. A short while ago, we issued a press release announcing our Q1 2024 financial results and recent business highlights. That press release and the slides that are being used on today's webcast can be found in the Investors section of Invivyd's website under the press release and Events and Presentations sections, respectively. Today's discussion will be led by Marc Elia, Chairman of Invivyd's Board of Directors and Chairman of the Executive Committee of the Board. He's joined by Jeremy Gowler, Interim CEO and Chief Operating and Commercial Officer; Bill Duke, Chief Financial Officer; Dr. Robert Allen, Chief Scientific Officer; and Dr. Mark Wingertzahn, Senior Vice President of Clinical Development and Medical Affairs. During today's discussion, we will be making forward-looking statements concerning, among other things, our corporate and commercial strategy, our research and development activities, our regulatory plans, certain financial guidance, our future prospects, and other statements that are not historical facts. These forward-looking statements are covered within the meaning of the Private Securities Litigation Reform Act and are subject to various risks, assumptions, and uncertainties that may change over time and cause our actual results to differ materially from those expressed or implied today. These forward-looking statements speak only as of the date of this call, and Invivyd assumes no duty to update such statements. Additional information on the risk factors that could affect Invivyd's business can be found in our filings made with the U.S. Securities and Exchange Commission, including our most recent Form 10-K, which is also available on our website. I will now turn the call over to Marc.

Thanks, Scott, and thank you all for joining the call. A quick housekeeping note, this will be Scott's last quarterly call. He is moving on from Invivyd to spend this summer and potentially start his own business. We wish him the best and thank him for his help in getting us here. To business. Turning to Slide 4. The last few months have been transformational for Invivyd. Invivyd has been built to address the unique scientific, medical, and social challenges presented by SARS-CoV-2 and potentially other viruses in the future. In 2023, SARS-CoV-2 remained a leading cause of death for Americans and that is to say nothing of the broad medical misery imposed by this uniquely transmissible and dangerous multi-organ virus. When we talk about building a company to meet the challenges of SARS-CoV-2, we mean that we believe we are pioneering a brand-new approach to antibody prophylactics and therapeutics. Engineered antibodies represent the promise of conferring to vulnerable populations the immune response to viral threats that we all wish we could have following vaccination or infection, an immune response that may be necessary for staying safe and well rather than the immune response that keeps us alive but at continuous risk. Obviously, the risk of SARS-CoV-2 is highest for the immunocompromised population who today benefit least from vaccination and represent a disproportionately high share of ongoing hospitalizations and deaths. We're starting our journey serving their needs but see the possibility of serving broader populations as we advance our technology and strategy. Broadly, our strategy is to combine the potential for high efficacy and attractive safety of modern monoclonal antibodies or mAbs directed against the SARS-CoV-2 spike protein with the opportunity for product evolution, one commonly seen in the vaccine industry. We set out on this mission because to us, it represents the only viable approach for bringing high-value medical options to populations in need. At this point, we see an attractive commercial opportunity for PEMGARDA in the near term, a rapid, compact, capital-efficient pathway to generating novel options for two distinct use cases: PrEP and potentially treatment, and a scientific engine devoted to repeatable, reliable, best-in-class molecule generation. Of course, major questions have surrounded this strategy for now almost two years, largely regulatory and operational. We're thrilled that over the last year, we have started to answer those questions more definitively in partnership with a highly motivated and thoughtful regulator in the U.S. Food and Drug Administration. The recent emergency use authorization for PEMGARDA for PrEP of COVID-19 in certain adults and adolescents who have moderate-to-severe immune compromise, and now the opportunity to file an application for EUA for treatment of mild to moderate symptomatic COVID-19 in a similar immunocompromised population, both represent the growing alignment between the core of our strategy and the posture of the major U.S. medical authority. Our aim is to build on and expand these early successes now by innovating to improve our products on all dimensions: the resistance to evasion that can be built into them, the potency of our antibodies, and accompanying improvements in dose therapeutic index and form factor they might offer, along with the clinical data that we hope can substantiate the broad use of antibody products in the future. Our agenda today is unique for a regular quarterly call. While we will review certain elements of our recent business progress, we will also provide context for the scientific and clinical thinking that underpins our corporate and commercial strategy and our enthusiasm for the future of Invivyd. This is not an R&D day; we will move relatively quickly through some concepts and hope that as you reflect on what you hear and read, you can engage with us on a follow-up basis if it's helpful following today's call. We have heard clearly from many of you that there are gaps in your understanding of our technologies, and we would like to take this opportunity to fill in those gaps so you can understand our company better moving forward through the launch. We believe that Invivyd's bespoke, proprietary, and fully integrated discovery technologies, combined with potential rapid development pathways, represent an impressive competitive advantage designed to keep Invivyd serving vulnerable populations with high-value commercial products engineered to treat and protect from serious viral threats indefinitely. We see the technological core of this engine as substantiating the economic vision for our firm, which is to advance high-value novel medicines with high speed, high capital efficiency, and high confidence to ensure that shareholders also benefit from the substantial medical value we aim to create for vulnerable populations. A few final notes before we move on with our agenda. We are well engaged in a search for a permanent CEO, but we will not comment further at this time. Also, Jeremy Gowler will comment on multiple elements of the early PEMGARDA launch, but we will not be disclosing any more granular detail than that which he will walk through in his prepared remarks, nor will we comment on any early sales trends other than to say that at this point, we are pleased with the organic demand we believe we're observing in the field. We have been moving quickly to establish the mechanical infrastructure, the institutional knowledge, and the experience base that will allow appropriate vulnerable populations, their healthcare providers, and broad health systems to access PEMGARDA routinely. I'll now turn the call over to Bill Duke, the CFO of Invivyd, to discuss our financial results and guidance.

Thank you, Marc. Turning to Slide 5. We ended Q1 2024 with cash and cash equivalents of $189.4 million. We did not record any PEMGARDA revenue in the first quarter as orders and shipments began in April. In April 2024, we announced that following a comprehensive strategic review, the company is improving its projected 2024 year-end cash position by approximately $20 million to $25 million. Our updated cash guidance improvement was built to include the anticipated spend on 2024 incremental clinical commitments associated with our potential treatment EUA. The improvements were realized through comprehensive resource realignment, ensuring robust investment in the commercial launch of PEMGARDA in the discovery of novel monoclonal antibodies. We have recently undertaken a commitment to filing a second EUA application for PEMGARDA, focusing on the treatment of mild to moderate symptomatic COVID-19 for certain immunocompromised people. This is a potentially transformational opportunity for Invivyd near term as we move into the summer and fall, and we consider this route as a future cornerstone for rapid development of innovative molecules. We will not, however, alter our year-end cash and top-line revenue guidance even if we achieve EUA treatment. At this point, we feel very comfortable with our near-term economic opportunity and look forward to updating our estimates in the fall at the earliest. Finally, as Marc mentioned, we look forward to continuing to innovate and introduce additional novel antibodies. We have studied the time and costs associated with generating the PEMGARDA clinical package that support PrEP and potential treatment. Going forward, we believe we can significantly reduce our clinical development time and costs, and we will look forward to sharing more detail soon. As you have seen from our prior descriptions of the target population and our recently disclosed commercial pricing, these use cases represent a total addressable market measured in billions of annual revenue when considering the roughly 500,000 people in the U.S. who are the most vulnerable and our initial focus. We are working to realize that potential and aim to expand the populations we can serve as our technology and strategy allow. With that, I'll turn the call over to Jeremy to update you on our launch.

Thanks, Bill. Moving to Slide 6. PEMGARDA is a high-value medicine for moderately to severely immunocompromised individuals who are in urgent need of protection from COVID-19. It fills a critical need not otherwise addressed in the marketplace today. Overall, we are very pleased with the strong interest we've seen thus far from patients and providers. Since authorization, we have received a surprising and gratifying level of unsolicited inquiries into our call center. Our field teams are having many positive interactions with our customers and are experiencing a high degree of interest in PEMGARDA. Now we are going through the logistics phase of the launch, where we are managing the processes around institution and payer access to ensure that PEMGARDA is broadly and conveniently available to those whom it is authorized. We are moving to ensure that PEMGARDA awareness and logistical support are in place prior to the broadest activation of healthcare provider and patient interest in the coming months. Of note, PEMGARDA represents our first-generation technology. As we will discuss later on in the call, we already have a follow-up map in VYD2311, which we believe holds the potential to have an improved product profile. The work we are doing today with PEMGARDA, we believe will pave the way for VYD2311 to seamlessly slot in behind it and build on PEMGARDA's anticipated success. Turning to Slide 7. We are a little more than six weeks post-authorization and the commercial organization and functions supporting it have been hard at work to execute the PEMGARDA launch. Our manufacturing colleagues worked very quickly to have product available within a week of authorization. In parallel, we contracted with three major distributors to ensure that our customers could procure PEMGARDA via their preferred procurement partner and subsequently shipped our first order. As of late, our focus has been on securing reimbursement and access. In mid-April, we announced that the U.S. Centers for Medicare and Medicaid Services, or CMS, published two healthcare common procedure coding system codes or HCPCS codes, a Q-code covering product reimbursement for PEMGARDA and a product-specific M-code covering the administration. This is critical because CMS provides coverage for nearly half of the moderately to severely immunocompromised people at higher risk for severe COVID-19, whom we are targeting. In parallel, our national account management team has been working to secure commercial reimbursement for PEMGARDA with private payers to ensure that the other half of the moderately to severely immunocompromised people who are eligible for PEMGARDA can access it. Our team of key account managers recently hit the ground running after completing extensive training, and they are now all fully deployed and calling on our roughly 1,150 targeted accounts to build awareness for the product and drive uptake. The early focus is on securing inclusion of PEMGARDA on institutional formularies as needed. We have had positive engagement and we see institutions taking it through the formulary committee processes already, and some have already ordered product. With respect to the patient experience and access, we are putting an even greater focus on building out logistical support to assist moderate to severe immunocompromised people who are seeking PEMGARDA. This work includes the creation of an online infusion site finder to help those people trying to access PEMGARDA. This new tool, which will be accessible in the future on pemgarda.com, is under active development. In parallel, we are engaging with infusion providers outside of traditional institutions to support patient access to the product. Finally, we are excited about the potential to submit and receive an additional EUA for PEMGARDA focused on the treatment of mild-to-moderate symptomatic COVID-19 in certain immunocompromised people should it be granted by the FDA. Since the commercial pathway and infrastructure already exists for the antivirals like Veklury, we are excited to have this additional use case for the product beyond PrEP as another potential way to capitalize on the work done to bring PEMGARDA to market. We will look forward to updating you more on our sales and relevant trends as the launch progresses. I will now turn the call over to Mark Wingertzahn, SVP of Clinical Development and Medical Affairs. Over to you, Mark.

Thanks, Jeremy. It's been great to join Invivyd at a fascinating time for the company and patients in need. Turning to Slide 8. As a reminder, our EUA for PrEP for COVID-19 in certain adults and adolescents who have moderate-to-severe immune compromise is based upon the ongoing Canopy Phase III clinical trial that includes two cohorts. First, we have a single-arm open-label cohort in immunocompromised subjects, the so-called Cohort A. Second, there is a randomized double-blind safety cohort in people at risk of SARS-CoV-2 infection from regular face-to-face meetings with exploratory clinical event endpoints, the so-called Cohort B. We have collected exploratory information on COVID events in both arms on an ongoing basis. Although obviously, the lack of a placebo arm renders the interpretation of events in the cohort A a bit more opaque. Moving to Slide 9. As a reminder, in order to meet the immunobridging endpoint agreed to with the FDA, we dosed to very high titers and then allowed the titers to decay with ordinary antibody pharmacokinetics subject to the half-life of VYD222, now PEMGARDA. You can well imagine that a redose will produce another major boost to titers, which we then expect will fall at a similar rate. Every dose involves a phase with very high titers, which then descend to lower levels; we look forward to seeing how we accrue any events we collect after our day 90 calculation in trough titers. Perhaps prior to a second dose, a time period that may give us information that could help us calibrate dose optimization going forward. Turning to Slide 10. As a reminder, we began the CANOPY clinical trial going into and then through the fall/winter 2023-2024 JN.1 wave. As a result, we saw a relatively robust attack rate in our study of about 3% to 5%. Although CANOPY was not prospectively designed or powered to demonstrate protection from symptomatic COVID-19, the analysis of exploratory endpoints of symptomatic COVID-19 events in CANOPY were unrelated to the FDA's review of our EUA application; we note the events have exploratory value as we consider the titers that may be associated with various levels of protection and think about dose and product profiles going forward. We have previously disclosed that in Cohort B, our double-blind placebo-controlled cohort, we observed protection of 100% through day 67, a period that overlapped with very high sVNA titers. Through day 90, we saw one breakthrough infection in the Pemivibart arm compared to eight in the Placebo arm, yielding a relative risk reduction of approximately 94%. As highlighted on the previous slide, while we are aware that additional cases of COVID-19 have occurred in Cohort A and Cohort B post day 90, we are awaiting the upcoming analysis of the second dose blinded 90-day interval that will add additional resolution to our thinking. We look forward to sharing these data later this summer. Turning to Slide 11. Importantly, we recently announced our intention to submit an EUA request for PEMGARDA for the treatment of mild to moderate symptomatic COVID-19 in certain immunocompromised people. As described in our press release, we view this as a logical and welcome complement to our overall serial monotherapy bridging paradigm and a reassuring reminder of the intellectual alignment between Invivyd and the U.S. FDA. The anticipated treatment EUA submission will leverage already existing data sets from our STAMP and CANOPY clinical trials. In parallel to the anticipated submission of the EUA request, we plan to design and initiate a compact clinical trial focused on generating confirmatory safety, pharmacokinetic, and clinical virology data. Importantly, treatment of mild-to-moderate symptomatic COVID-19 in certain immunocompromised people is a second use case for PEMGARDA and possibly follow-up molecules with shorter-term endpoints than PrEP, which may substantiate rapid innovation moving forward. Turning to Slide 12. This additional use case is important because even with vaccination, immunocompromised people are disproportionately impacted by severe COVID-19 outcomes and remain a major driver of ongoing hospitalization and death in the U.S. despite current small molecule treatment options. Moving to Slide 13. If authorized, PEMGARDA could be a welcome addition to the therapeutic armamentarium and a valuable potential option for certain people with moderate to severe immune compromise when alternative COVID-19 treatment options were not clinically appropriate or accessible. At present, there is no authorized antibody treatment for COVID-19, and among existing options, some are complicated by drug-drug interactions and others are mainly deployed in a hospital setting requiring burdensome repeat intravenous infusions on consecutive days. Turning to Slide 14. As we have seen since the beginning of COVID therapies, treatment option utilization ebbs and flows with overall viral presence. Nonetheless, in year five of the pandemic, COVID treatments remain heavily utilized. We are moving with considerable urgency as we believe that immunobridging provides us with a more rapid and efficient pathway to deliver an important COVID-19 treatment option, complementing our efforts with PrEP. I am now pleased to turn the call to Robbie to discuss our analytics and discovery technologies.

Thank you, Mark. Good afternoon. Many of you have shown interest in our work on virus evolution and our confidence in the quality and durability of PEMGARDA and our pipeline molecules. To begin, I want to introduce VivydTools, our proprietary software that tracks virus variation across COV-2 from various sources, including clinical sample sequence data and sequencing data from wastewater. Generally, variants that become clinically significant are detected in wastewater before they emerge broadly. Wastewater data can also include sequences of viruses that do not become highly prevalent in the clinic, but they offer a comprehensive view of the virus's mutational landscape over time. We use this tool for two main purposes: to aid in activity prediction and monitoring, and increasingly to support proprietary discovery approaches that give us a unique edge in the field. On the left side of the panel on Slide 16, at Invivyd, we document and analyze variation observed across the spike protein, focusing on low-frequency polymorphic variations. The graphs displayed depict changes in the amino acids from positions 403 to 432. This data allows us to view multiple datasets at once, although some graphs have more variability than others, indicating different levels of polymorphic exploration at specific residues as the virus evolves. By assessing epitopic sites for our antibodies, including VYD222, we can evaluate how mutable our epitope is. In the areas we monitor related to the assigned epitope of VYD222, we have seen polymorphic stability from Omicron's emergence to today. Moving to Slide 17, once we select an antibody for development, we cannot alter that choice. Therefore, monitoring and analyzing variation becomes crucial in designing our screens and selecting antibody candidates. When examining variation in the Spike and RBD areas we aim to target with our monoclonal antibody, we observe evolution, including significant structural changes and reconvergence along previously explored pathways. While we cannot specifically predict variation, we are starting to gain insights into the nature of SARS-CoV-2 evolution. If we can establish a data-driven intelligence approach for anticipating future changes, we can identify theoretical or synthetic proteins that may not exist yet but represent potential future variants we want to prepare for. This enables us to utilize our proprietary discovery technology, which leverages an advanced yeast-based mAb optimization platform from Adimab, to perform operations that would be impractical with less sophisticated technology. On Slide 18, this means we can utilize our knowledge of previously circulated and currently circulating viruses, along with synthetic predictions of what might emerge, to conduct logic-driven discovery screens. This allows us to direct the platform to identify specific antibodies based on the framework of adintrevimab and Pemivibart, which neutralize strains like XBB and JN.1 while avoiding interactions with residues we may be concerned about. We can select these candidate antibodies and confirm their activity against both current viruses and those we anticipate may evolve in the future. On Slide 19, we are seeking antibodies unaffected by the mammalian immune system, aiming for novel molecules that can undergo rapid, efficient development. With each generation of molecules, we strive to enhance our confidence in their resistance to variation and improve their overall pharmaceutical properties. This approach began with adintrevimab, developed early on from a SARS-CoV-1 antibody against the Wuhan virus. At that time, we believed the critical product attribute came from conserving H2 access, but the Omicron shift highlighted that immune evasion is a significant aspect of the discovery process. Moving to Pemivibart, which is adintrevimab optimized against BA.2, we have maintained a criterion of backward-looking neutralization of ancestral pre-Omicron lineages. This constraint has resulted in a promising conservation of the Pemivibart epitope as the virus evolves, although it does impose a slight potency penalty against recent circulating strains. Our next anticipated clinical candidate, VYD2311, aims to enhance Pemivibart's potency and resistance to variation. We look forward to sharing more about 2311 soon, as its early profile shows promise in terms of dosage, therapeutic index, and administration route. Earlier in our Discovery phase, we are now integrating forward-looking synthetic antigens to create antibodies that incorporate anticipatory intelligence, a process we will continue to monitor and refine. We are exploring beyond the current boundaries, identifying and qualifying molecules designed across multiple dimensions to address likely future scenarios – a unique approach in biopharmaceuticals as far as we know. Now, I will turn it back to Mark for some closing thoughts before we enter the Q&A session.

Thanks, Robbie. In summary, as shown on Slide 20, we're constantly tracking, analyzing and considering variation. We do it both to monitor the probable activity of our current drug, Pemivibart; to monitor the stability of epitopes for candidate drugs, including 2311 and others; and now also to generate analytic findings that allow us to build antibodies that anticipate probable changes and clearly retain activity. You will have and will, in the future, see various results of neutralization assays on our and other antibodies. We would encourage you to interpret those data with caution. Our colleagues at AstraZeneca on the EVUSHELD Fact Sheet characterized changes in neutralizing potency of less than five-fold as 'no change,' which speaks to the variable nature of these assays and the tenuous uncertain relationship between those precise assay results and overall clinical activity. Worse, when and if an assay has changed or our laboratory has switched as a vendor, comparability becomes more problematic. As a consequence, while we at Invivyd will continue monitoring neutralization carefully, we will not update you all on an ad hoc basis. Rather, we will communicate our findings with the FDA and update our product fact sheet when applicable. The sum of all this work is that we believe we have excellent and growing evolutionary intelligence on SARS-CoV-2 and a unique ability to operationalize that intelligence. Our work can never be perfect as we are up against Mother Nature, who always has tricks up her sleeve. However, we are highly encouraged by our recent progress in our basic science, our clinical development, our growing regulatory alignment, and our commercial efforts. Our goal with innovation over time will be to substantially expand the population to whom we can offer COVID-19 protection and treatment, to improve the profile of our products, and thereby to substantially increase the medical value of our products for patients and providers and therefore, our value creation for shareholders. I'd like to ask the operator to open the line for questions.

Our first question comes from Maxwell Skor of Morgan Stanley.

Congratulations on the progress. So to start with, can you elaborate a bit more on your marketing strategy, including whether you're exploring direct-to-consumer campaigns and which physician specialty is most likely to prescribe PEMGARDA? And then finally, you announced plans to initiate a compact clinical trial. I'm wondering how you'll leverage these data and whether you're running this trial in response to specific FDA feedback?

Thanks, Max. Let me quickly touch on the second question you raised first, and I'll ask Mark to add anything I forgot, which is to say our reference to a compact trial is, I think, described a bit in our original press release, but the basis for EUA submission is largely analytics and a little bit of incremental work from our prior clinical development work, STAMP and CANOPY specifically, as it goes to the treatment EUA, which I think is what you're referring to. So the nature of that confirmatory study embraces elements of pharmacokinetic safety and clinical virology. That study is under active development. I'm sure as we refine those elements, we'll share some more details with you. But very quickly, Mark, did I leave anything off of that?

No. To build on what you mentioned, the primary focus will be on assessing any treatment emergent resistance to Pemivibart, along with gathering safety and pharmacokinetic data. This will largely be an addition to the studies we have already conducted.

So I think Max, Jeremy can now give you a little more color on EUA, which is a pretty unique concept in pharmaceuticals, and I think has some boundaries and advantages that bear on your specific question about marketing.

Yes. Thanks, Max, and Marc for the introduction here. So I would say the early days were focused on raising healthcare provider awareness for the product, and that's a really critical part because if patients go into access a product and the healthcare provider knows nothing about it, then it kind of ends up at a dead end. So early days, we're focused on that as part of the launch. We have not ruled out not doing DTC in the future, and we're exploring that, and we do some targeted patient campaigns. What we also know a little bit about patients is these kind of sick, sick patients that we see, the immunocompromised, they are very active in their management of their health. And so we've seen a lot of organic interest online and in chat groups, et cetera, where there's a fair amount of interest in trying to access the product already. So we feel sometimes the patients are actually a little bit ahead of the healthcare providers in this regard, and we really do want to inform the healthcare providers early on. So that's the primary focus around the time of the launch, and we'll explore expanding beyond that as time progresses.

Our next question comes from the line of Patrick Trucchio of H.C. Wainwright & Co.

Congrats on all the progress at the launch and pipeline. Just a couple of follow-up questions from me. The first is, I think it was noted that the reimbursement codes, Q code and M code cover reimbursement for half of moderate to severe immunocompromised people at highest risk for severe COVID-19 that you're targeting. So I'm wondering how we should think about reimbursement for the other half of the target patient population, timing of reimbursement and just how we should anticipate kind of the launch going with that other half? And then separately, can you discuss the potential approval pathway for PEMGARDA's treatment in immunocompromised individuals, and when you would envision being able to submit for an EUA and maybe clarify the timeline, including time to submission to potential authorization separately. Just how meaningful you anticipate this label expansion may be for peak sales potential PEMGARDA?

Let me start with the second question, and then I'll return to Jeremy regarding your coverage inquiry. In our press release, we clearly indicated that our submission for EUA would be imminent; this usually means a timeframe of weeks rather than months or quarters, which would have altered our wording. We aim to convey that this is based on intellectual alignment, utilizing shared material and clinical experiences similar to our PrEP EUA. Ultimately, all these use cases rely on sVNA titer. Reflecting on EVADE and STAMP, the parent clinical studies that utilized adintrevimab, we employed the same dose, administration route, and titers, which supported both PrEP and treatment applications. What we are doing is extending this foundational approach into the broader PEMGARDA program while recognizing its potential as a notable addition to future antibodies, which have historically been effective in both roles. Hope that clarifies things, and stay tuned. We aim to provide more updates soon. Jeremy, back to you for the CMS and coverage...

Yes. On the commercial reimbursement side, we have our national account management team out there, earnestly working away and getting that for us. We understand the criticality of it given the other half of the population, as you mentioned. So we're encouraged by the initial engagement we're getting, but of course, there are processes and time that formularies need to go through, the payors go through other formularies. So we're working through that right now, but more to come as we go through this launch.

Our next question comes from the line of Evan Wang of Guggenheim Securities.

I have two questions. First, regarding pipeline development, I know there has been some focus on the discovery engine and next-generation products. Can you provide some insight into your approach moving forward? It seems there has been significant dialogue with the FDA lately, especially concerning the support for the EUA for PrEP and discussions about new treatments. Can you outline the development plans for VYD2311 and your thoughts on this? Secondly, I want to discuss the treatment opportunity further. How should we evaluate this given that PAXLOVID and VEKLURY are well-established markets, but there is talk around alternative treatments or options when these alternatives are not suitable or available?

Evan, this is Mark. I think navigating and leading a completely new field of medicine brings both excitement and some frustration for you as you seek specificity and precision, which is a subject of ongoing discussions and collaboration. When we are able to provide you with a clear picture of how we envision these developments, we will certainly do so. Over the past 12 to 18 months, starting from the December joint discussion between the FDA and EMA regarding the use of surrogates for expedited trials of COVID-19 antibody therapeutics and prophylactics, we have seen a growing alignment that we believe paves the way for innovative approaches. We are actively designing these strategies as we move forward. This is not meant to be evasive or to withhold information, but rather to acknowledge that these developments are changing as Invivyd identifies genuine opportunities to advance them. With PEMGARDA, we have a chance to expand its application. Our observations regarding the FDA indicate that they are highly thoughtful, engaged, and aware of the significant unmet needs. As we enhance that collaboration, we are eager to continue innovating these pathways and creating tailored, proprietary methods that may be facilitated by our distinct molecules and discovery engine. This is what you are witnessing unfold in real time. We look forward to how this new avenue will evolve in the coming weeks and months. On the topic of treatment, I will ask Mark to share his perspective on the opportunities we see. However, we have chosen not to adjust our guidance, so we may not be able to provide the specific estimates you would prefer regarding the size of the opportunity. Nonetheless, we are quite enthusiastic about it.

Thank you, Mark. I'm Mark's colleague here, and I've been involved in drug development for nearly 30 years. I want to emphasize that we will certainly refine and enhance our approach based on the framework provided by the FDA so far, not only for prevention but also for treatment. I believe this aligns with our understanding of remdesivir, which poses significant challenges for both healthcare providers and patients. The multiple infusions required in a very short time frame primarily limit its use to hospital settings. While PAXLOVID will remain an option, it comes with challenges related to drug interactions and limited effectiveness in eliminating viral levels compared to what a monoclonal antibody might achieve. This creates a compelling case for our product, particularly for immunocompromised patients who have numerous health issues and are often on several medications that could interact negatively with existing treatments.

One moment for our next question. Thank you. Our next question comes from the line of Michael Yee of Jefferies.

This is Jenna on for Mike. Our question is on what magnitude of orders or potential orders are you seeing right now, when are they coming? Have you shipped anything? And when would you start booking sales?

Thanks for the question. We have made some very preliminary disclosures in prior press releases that I'll ask you to take a read through one last time. But at this point, we're not going to go into any incremental detail. This is the early phase of the launch. It is very quickly going to be the middle phase of the launch. As we look forward to the summer and then the fall, we're obviously going to be in a position to give you some feedback and some information that is useful to you right? At this point, I think it's a little bit early, although we over here are quite encouraged. I don't know that anything we could respond to you with today would be particularly informative as it goes to understanding how the balance of the year is likely to play out. So stay tuned, and we are looking forward just as you are to getting into more of that detail as the launch progresses.

I am showing no further questions at this time. I would now like to turn it back to Marc Elia, Chairman of Invivyd's Board of Directors and Chairman of the Executive Committee of the Board for closing remarks.

Thank you, and thanks to all of you for joining the call today and for your interest in Invivyd.

Thank you for your participation in today's conference. This does conclude the program. You may now disconnect.