Nirmatrelvir

On Track to Report Topline Results for RSVHR, a Phase 2 Study of Zelicapavir in High-Risk Adults Infected with Respiratory Syncytial Virus (RSV), in 3Q 2025 Advancing Immunology Portfolio with Ongoing IND Enabling Studies of KIT Inhibitor EPS-1421 On Track to Announce STAT6 Development Candidate in 2H 2025 Operations Supported by Cash and Marketable Securities Totaling $216.7 Million at December 31, 2024 , as well as Continuing Retained Royalties WATERTOWN, Mass. --(BUSINESS WIRE)--Feb. 10, 2025-- Enanta Pharmaceuticals, Inc. (NASDAQ:ENTA), a clinical-stage biotechnology company dedicated to creating small molecule drugs for virology and immunology indications, today reported financial results for its fiscal first quarter ended December 31, 2024 . “2025 is primed to be a pivotal year for Enanta as we execute on multiple catalysts across our pipeline, including progression of our RSV compounds and expansion of our immunology portfolio. Recruitment for RSVHR, our Phase 2 study of zelicapavir in high-risk adults infected with RSV, is ongoing and we plan to report topline data in the third quarter of this year. Following the encouraging results from our pediatric RSV study, we look forward to working with regulators to align on the registration pathway for zelicapavir in children and await the results of RSVHR, a Phase 3 enabling trial for adults. With both zelicapavir and EDP-323, we have the leading portfolio of RSV candidates in clinical development today and are eager to develop potential first-in-disease and best-in-class treatments for patients suffering from RSV,” said Jay R. Luly , Ph.D., President and Chief Executive Officer at Enanta Pharmaceuticals . “Moving forward, we will be exploring potential partnership opportunities to advance our RSV program. Simultaneously, we are working to ensure readiness for the next phase of RSV clinical development in a strategic and capital efficient manner, thereby extending our cash runway into fiscal 2028.” Dr. Luly added, “In parallel, we are rapidly advancing and expanding our immunology portfolio targeting Type 2 immune diseases, with an initial focus on indications with fast proof-of-concept. We are making progress to advance EPS-1421, our lead candidate for our KIT inhibition program, with the goal of developing a best-in-class, oral treatment for chronic spontaneous urticaria and other mast cell driven diseases. We are also excited about the progress in our STAT6 program, where we are leveraging our expertise in medicinal chemistry to develop novel, potent and selective oral inhibitors that block the IL-4/IL-13 signaling pathway, with an initial indication in atopic dermatitis and future expansion opportunities in asthma and other diseases. We expect to select a lead development candidate for STAT6 in the second half of this year and look forward to continuing to build out our immunology portfolio with the announcement of a third program this year. We have a busy year ahead with multiple opportunities to drive value for the company and move us closer to bringing important treatments to patients in need.” Fiscal First Quarter Ended December 31, 2024 Financial Results Total revenue for the three months ended December 31, 2024 was $17.0 million and consisted of royalty revenue from worldwide net sales of MAVYRET®/MAVIRET®, AbbVie’s eight-week treatment for chronic hepatitis C virus, compared to $18.0 million for the three months ended December 31, 2023 . The decrease in revenue is due to a decline in AbbVie’s sales of MAVYRET®/MAVIRET®. A portion (54.5%) of Enanta’s ongoing royalty revenue from AbbVie’s net sales of MAVYRET®/MAVIRET® is paid to OMERS, one of Canada’s largest defined benefit pension plans, pursuant to a royalty sale transaction affecting royalties earned after June 2023 . For financial reporting purposes, the transaction was treated as debt, with the upfront purchase payment of $200.0 million recorded as a liability. Each quarter, Enanta records 100% of the royalty earned as revenue and then amortizes the debt liability proportionally as 54.5% of the cash royalty payments are paid to OMERS through June 30, 2032 . This is subject to a cap of 1.42 times the purchase payment, after which point 100% of the cash royalty payments will be retained by Enanta. Interest expense was $2.0 million for the three months ended December 31, 2024 , as compared to interest expense of $3.4 million for the three months ended December 31, 2023 . Research and development expenses totaled $27.7 million for the three months ended December 31, 2024 , compared to $36.4 million for the three months ended December 31, 2023 . The decrease was due to a decrease in expenses for Enanta’s virology program due to timing of clinical trials in the company’s RSV program and to a lesser extent, a decrease in costs associated with Enanta’s COVID-19 program, as the company previously announced any further COVID-19 efforts would be in the context of collaborations. General and administrative expenses totaled $12.8 million for the three months ended December 31, 2024 , compared to $16.5 million for the three months ended December 31, 2023 . The decrease was due to a decrease in legal expenses related to the company’s patent infringement lawsuit against Pfizer. Interest and investment income, net, totaled $2.8 million for the three months ended December 31, 2024 , compared to $4.3 million for the three months ended December 31, 2023 . The decrease was due to lower cash and investment balances year-over-year. Enanta recorded an income tax benefit of $0.4 million for the three months ended December 31, 2024 , and $0.6 million for the three months ended December 31, 2023 . The income tax benefit in both periods was driven by interest earned on a pending $28 million federal income tax refund. Net loss for the three months ended December 31, 2024 was $22.3 million , or a loss of $1.05 per diluted common share, compared to a net loss of $33.4 million , or a loss of $1.58 per diluted common share, for the corresponding period in 2023. Enanta’s cash, cash equivalents and short-term marketable securities totaled $216.7 million at December 31, 2024 . Enanta expects that its current cash, cash equivalents and marketable securities, as well as its retained portion of future royalty revenue, will be sufficient to meet the anticipated cash requirements of its existing business and development programs into fiscal year 2028. Virology RSV Enanta aims to develop a first and leading RSV antiviral treatment portfolio to help all populations at high-risk for severe outcomes from RSV infection. This includes zelicapavir, Enanta’s lead, oral N-protein inhibitor, and EDP-323, its oral L-protein inhibitor, both of which received Fast Track designation from the U.S. Food and Drug Administration . Zelicapavir is being evaluated in RSVHR, a Phase 2b, randomized, double-blind, placebo-controlled study in adults with RSV infection who are at high risk of complications, including age over 65 years and/or those with congestive heart failure, chronic obstructive pulmonary disease or asthma. Enrollment in RSVHR is progressing, and the company is targeting completion in the current Northern Hemisphere RSV season with topline data in the third quarter of 2025. In December 2024 , Enanta announced results from a Phase 2 randomized, double-blind, placebo-controlled study in hospitalized and non-hospitalized pediatric RSV patients aged 28 days to 3 years old. In the study of 96 patients, an antiviral effect was observed for the primary and secondary virology endpoints in the overall pooled efficacy population. The primary endpoint in Part 2 of the study, which focused on virology, showed a pronounced antiviral effect with a 1.4 log decline in viral load at Day 5 compared to placebo. Additionally, a rapid and robust virologic effect was observed in a prespecified subset of patients who were randomized within 3 days of symptom onset, with a 1.2 log decline in viral load at Day 5 compared to placebo. The study also showed that zelicapavir demonstrated a favorable safety profile and was well-tolerated in this pediatric population. Enanta’s second clinical RSV candidate, EDP-323, is a novel oral, direct-acting antiviral selectively targeting the RSV L-protein. In September 2024 , Enanta announced positive results for EDP-323 in a Phase 2a challenge study of healthy adults infected with RSV, in which treatment with EDP-323 achieved highly statistically significant reductions in both viral load and clinical symptoms compared to placebo, as well as demonstrated a favorable safety and tolerability profile. With positive results from both zelicapavir and EDP-323, Enanta has the most advanced portfolio of RSV therapeutic candidates, which provides important optionality and the potential for first-in-disease and best-in-disease development strategies. The company expects to work with regulators to align on the registration pathway for zelicapavir in pediatric patients and will look to complete RSVHR, a Phase 3 enabling trial in high-risk adults. In addition, Enanta will evaluate potential partnership opportunities to advance its RSV assets to the next stage of clinical development. Zelicapavir is being evaluated in RSVHR, a Phase 2b, randomized, double-blind, placebo-controlled study in adults with RSV infection who are at high risk of complications, including age over 65 years and/or those with congestive heart failure, chronic obstructive pulmonary disease or asthma. Enrollment in RSVHR is progressing, and the company is targeting completion in the current Northern Hemisphere RSV season with topline data in the third quarter of 2025. In December 2024 , Enanta announced results from a Phase 2 randomized, double-blind, placebo-controlled study in hospitalized and non-hospitalized pediatric RSV patients aged 28 days to 3 years old. In the study of 96 patients, an antiviral effect was observed for the primary and secondary virology endpoints in the overall pooled efficacy population. The primary endpoint in Part 2 of the study, which focused on virology, showed a pronounced antiviral effect with a 1.4 log decline in viral load at Day 5 compared to placebo. Additionally, a rapid and robust virologic effect was observed in a prespecified subset of patients who were randomized within 3 days of symptom onset, with a 1.2 log decline in viral load at Day 5 compared to placebo. The study also showed that zelicapavir demonstrated a favorable safety profile and was well-tolerated in this pediatric population. Enanta’s second clinical RSV candidate, EDP-323, is a novel oral, direct-acting antiviral selectively targeting the RSV L-protein. In September 2024 , Enanta announced positive results for EDP-323 in a Phase 2a challenge study of healthy adults infected with RSV, in which treatment with EDP-323 achieved highly statistically significant reductions in both viral load and clinical symptoms compared to placebo, as well as demonstrated a favorable safety and tolerability profile. With positive results from both zelicapavir and EDP-323, Enanta has the most advanced portfolio of RSV therapeutic candidates, which provides important optionality and the potential for first-in-disease and best-in-disease development strategies. The company expects to work with regulators to align on the registration pathway for zelicapavir in pediatric patients and will look to complete RSVHR, a Phase 3 enabling trial in high-risk adults. In addition, Enanta will evaluate potential partnership opportunities to advance its RSV assets to the next stage of clinical development. In December 2024 , Enanta announced results from a Phase 2 randomized, double-blind, placebo-controlled study in hospitalized and non-hospitalized pediatric RSV patients aged 28 days to 3 years old. In the study of 96 patients, an antiviral effect was observed for the primary and secondary virology endpoints in the overall pooled efficacy population. The primary endpoint in Part 2 of the study, which focused on virology, showed a pronounced antiviral effect with a 1.4 log decline in viral load at Day 5 compared to placebo. Additionally, a rapid and robust virologic effect was observed in a prespecified subset of patients who were randomized within 3 days of symptom onset, with a 1.2 log decline in viral load at Day 5 compared to placebo. The study also showed that zelicapavir demonstrated a favorable safety profile and was well-tolerated in this pediatric population. Immunology Enanta’s immunology portfolio is focused on designing and developing highly potent and selective, oral small molecule inhibitors for the treatment of inflammatory diseases, by targeting key drivers of the type 2 immune response. KIT Inhibitors: EPS-1421, Enanta’s lead candidate, is a novel, potent and selective oral inhibitor of KIT, designed to treat chronic spontaneous urticaria and other indications by depleting mast cells, thereby addressing a primary driver of these diseases. EPS-1421 inhibits KIT with nanomolar potency in both binding and cellular assays, and has sub-nanomolar activity in vivo. EPS-1421 is also highly selective for KIT versus other kinases and, preclinically, has demonstrated good in vitro and in vivo ADME properties. Enanta is conducting scale-up activities and IND enabling studies in 2025. STAT6 Inhibitors: Enanta is advancing novel, potent and selective oral inhibitors of STAT6 for the treatment of type 2 immune driven diseases. The company will initially focus on atopic dermatitis and expand into other indications that block the IL-4/IL-13 signaling pathway, thereby addressing a primary driver of these diseases. Enanta’s prototype inhibitors demonstrate potent activity and high selectivity for STAT6 over other STATs in both biochemical and cellular assays. Additionally, the prototype inhibitors demonstrate systemic in vivo target engagement after ex vivo IL-4 stimulation. The company is conducting lead optimization activities and plans to select a STAT6 lead candidate in the second half of 2025. Enanta plans to expand its presence in immunology with the introduction of a third program in 2025. KIT Inhibitors: EPS-1421, Enanta’s lead candidate, is a novel, potent and selective oral inhibitor of KIT, designed to treat chronic spontaneous urticaria and other indications by depleting mast cells, thereby addressing a primary driver of these diseases. EPS-1421 inhibits KIT with nanomolar potency in both binding and cellular assays, and has sub-nanomolar activity in vivo. EPS-1421 is also highly selective for KIT versus other kinases and, preclinically, has demonstrated good in vitro and in vivo ADME properties. Enanta is conducting scale-up activities and IND enabling studies in 2025. STAT6 Inhibitors: Enanta is advancing novel, potent and selective oral inhibitors of STAT6 for the treatment of type 2 immune driven diseases. The company will initially focus on atopic dermatitis and expand into other indications that block the IL-4/IL-13 signaling pathway, thereby addressing a primary driver of these diseases. Enanta’s prototype inhibitors demonstrate potent activity and high selectivity for STAT6 over other STATs in both biochemical and cellular assays. Additionally, the prototype inhibitors demonstrate systemic in vivo target engagement after ex vivo IL-4 stimulation. The company is conducting lead optimization activities and plans to select a STAT6 lead candidate in the second half of 2025. Enanta plans to expand its presence in immunology with the introduction of a third program in 2025. EPS-1421, Enanta’s lead candidate, is a novel, potent and selective oral inhibitor of KIT, designed to treat chronic spontaneous urticaria and other indications by depleting mast cells, thereby addressing a primary driver of these diseases. EPS-1421 inhibits KIT with nanomolar potency in both binding and cellular assays, and has sub-nanomolar activity in vivo. EPS-1421 is also highly selective for KIT versus other kinases and, preclinically, has demonstrated good in vitro and in vivo ADME properties. Enanta is conducting scale-up activities and IND enabling studies in 2025. Enanta is advancing novel, potent and selective oral inhibitors of STAT6 for the treatment of type 2 immune driven diseases. The company will initially focus on atopic dermatitis and expand into other indications that block the IL-4/IL-13 signaling pathway, thereby addressing a primary driver of these diseases. Enanta’s prototype inhibitors demonstrate potent activity and high selectivity for STAT6 over other STATs in both biochemical and cellular assays. Additionally, the prototype inhibitors demonstrate systemic in vivo target engagement after ex vivo IL-4 stimulation. The company is conducting lead optimization activities and plans to select a STAT6 lead candidate in the second half of 2025. Corporate On February 3, 2025 , Enanta filed a notice of appeal with the United States Court of Appeals for the Federal Circuit related to a June 2022 lawsuit the company filed in the United States District Court for the District of Massachusetts against Pfizer, Inc. seeking damages for infringement of U.S. Patent No. 11,358,953 (the ’953 Patent) in the manufacture, use and sale of Pfizer’s COVID-19 antiviral, Paxlovid™ (nirmatrelvir tablets; ritonavir tablets). Enanta plans to issue its fiscal second quarter financial results press release on May 12, 2025 . About Enanta Pharmaceuticals, Inc. Enanta is using its robust, chemistry-driven approach and drug discovery capabilities to become a leader in the discovery and development of small molecule drugs with an emphasis on indications in virology and immunology. Enanta’s clinical programs are currently focused on respiratory syncytial virus (RSV) and its earlier-stage immunology pipeline aims to develop treatments for inflammatory diseases by targeting key drivers of the type 2 immune response, including KIT and STAT6 inhibition. Glecaprevir, a protease inhibitor discovered by Enanta, is part of one of the leading treatment regimens for curing chronic hepatitis c virus (HCV) infection and is sold by AbbVie in numerous countries under the tradenames MAVYRET® ( U.S. ) and MAVIRET® (ex- U.S. ) (glecaprevir/pibrentasvir). A portion of Enanta’s royalties from HCV products developed under its collaboration with AbbVie contribute ongoing funding to Enanta’s operations. Please visit www.enanta.com for more information. Forward Looking Statements This press release contains forward-looking statements, including statements with respect to the prospects for advancement of Enanta’s clinical programs in RSV and its preclinical programs targeting KIT and STAT6 inhibition. Statements that are not historical facts are based on management’s current expectations, estimates, forecasts and projections about Enanta’s business and the industry in which it operates and management’s beliefs and assumptions. The statements contained in this release are not guarantees of future performance and involve certain risks, uncertainties and assumptions, which are difficult to predict. Therefore, actual outcomes and results may differ materially from what is expressed in such forward-looking statements. Important factors and risks that may affect actual results include: the impact of development, regulatory and marketing efforts of others with respect to vaccines and competitive treatments for RSV; the discovery and development risks of Enanta’s programs in virology and immunology; Enanta’s lack of clinical development experience; Enanta’s need to attract and retain senior management and key research and development personnel; Enanta’s need to obtain and maintain patent protection for its product candidates and avoid potential infringement of the intellectual property rights of others; and other risk factors described or referred to in “Risk Factors” in Enanta’s Form 10-K for the fiscal year-ended September 30, 2024 , and any other periodic reports filed more recently with the Securities and Exchange Commission . Enanta cautions investors not to place undue reliance on the forward-looking statements contained in this release. These statements speak only as of the date of this release, and Enanta undertakes no obligation to update or revise these statements, except as may be required by law. Tables to Follow 2024 2023 $ 16,959 $ 18,003 27,656 36,371 12,846 16,518 40,502 52,889 (23,543 ) (34,886 ) (1,962 ) (3,441 ) 2,799 4,298 (22,706 ) (34,029 ) 416 622 $ (22,290 ) $ (33,407 ) $ (1.05 ) $ (1.58 ) $ (1.05 ) $ (1.58 ) 21,238 21,088 21,238 21,088 2024 2024 $ 84,349 $ 37,233 132,342 210,953 7,718 6,646 10,684 12,413 32,444 31,999 608 608 268,145 299,852 37,368 32,688 39,675 40,658 3,360 3,360 94 94 $ 348,642 $ 376,652 $ 4,726 $ 8,002 10,575 13,547 32,743 34,462 1,006 1,524 49,050 57,535 129,738 134,779 56,453 53,943 1,350 1,350 235 231 236,826 247,838 111,816 128,814 $ 348,642 $ 376,652 View source version on businesswire.com: https://www.businesswire.com/news/home/20250210108421/en/ Media and Investors Contact: Jennifer Viera jviera@enanta.com Source: Enanta Pharmaceuticals, Inc.

Treatment immunobridging analysis, routinely updated for contemporary SARS-CoV-2 variants, compares pemivibart antiviral titers to adintrevimab antiviral titers from the company’s previous Phase 2/3 clinical trial of adintrevimab for the treatment of COVID-19 (STAMP), in which adintrevimab conferred a 66% to 74% reduction in risk of hospitalization or death from COVID-19 compared to placebo depending on time of therapy startMost recent updated analysis provided to FDA, incorporating current dominant SARS-CoV-2 variant XEC neutralization data, demonstrated substantially higher pemivibart titers in the critical early phase post-dosing (Days 0-5) as compared to adintrevimab Data provided to FDA includes supportive data showing attractive comparison of antiviral activity between pemivibart and monoclonal antibodies previously authorized for treatment of COVID-19Pemivibart safety profile demonstrated in the company’s CANOPY Phase 3 clinical trial supports the EUA amendment request; further, no additional reports of anaphylaxis have been identified during post-authorization use of PEMGARDA for COVID-19 pre-exposure prophylaxis (PrEP) to dateUpdated analysis builds upon multiple comparable analyses submitted to the FDA beginning July 2024 for prior SARS-CoV-2 variants, all showing consistent antiviral titer relationships and a favorable risk-benefit profile WALTHAM, Mass., Jan. 27, 2025 (GLOBE NEWSWIRE) -- Invivyd, Inc. (Nasdaq: IVVD), a biopharmaceutical company devoted to delivering protection from serious viral infectious diseases, today announced the submission to the U.S. Food and Drug Administration (FDA) of an updated immunobridging analysis of pemivibart as ongoing support of a potential amendment to the Emergency Use Authorization (EUA) for pemivibart, a half-life extended investigational monoclonal antibody (mAb), to include the treatment of mild-to-moderate symptomatic COVID-19 in certain immunocompromised patients for whom alternative COVID-19 treatment options are not accessible or clinically appropriate. PEMGARDA™ (pemivibart) received an EUA from the FDA in March 2024 for pre-exposure prophylaxis (PrEP) of COVID-19 in certain adults and adolescents with moderate-to-severe immune compromise. This updated treatment immunobridging analysis, incorporating dominant SARS-CoV-2 variant XEC neutralization data, is similar to the approach and data that supported the PEMGARDA PrEP EUA. The updated analysis is in line with the prior, positive treatment immunobridging analyses of pemivibart versus its parent molecule, adintrevimab, and other comparator mAbs based on prior virus variants, previously submitted to the FDA in mid-2024 and late-2024 in support of the company’s EUA amendment request for COVID-19 treatment. The comparison between pemivibart and adintrevimab illustrates serum virus neutralizing antibody (sVNA) titers, the clinical measure of antiviral activity, conferred by pemivibart substantially exceed those of adintrevimab for the first four days post dosing, after which titers fall modestly below. As a long-acting mAb, pemivibart would be expected to exert meaningful antiviral activity for many months following a single dose. In the STAMP clinical trial, adintrevimab conferred the majority of its maximum antiviral effect by Day 5 and demonstrated a viral load reduction generally in line with PAXLOVID®1. Because pemivibart is dosed intravenously, higher serum drug concentration and corresponding antiviral activity are delivered immediately, compared to the slower distribution of intramuscularly administered adintrevimab. Pemivibart’s pharmacodynamic profile therefore may have some benefit in modifying viral infection and associated clinical outcomes as compared to adintrevimab. Prior randomized control trials of COVID-19 mAbs have underscored the benefit of deploying maximum antiviral activity as early as possible in the treatment of active infection in avoiding hospitalization and adverse morbid/mortal outcomes2. If an EUA amendment for COVID-19 treatment is granted, Invivyd intends to assess the virologic profile of pemivibart in a clinical study designed in collaboration with the FDA. The standing treatment EUA request supporting pemivibart for the treatment of COVID-19 in certain immunocompromised patients for whom alternative COVID-19 treatment options, such as PAXLOVID® (nirmatrelvir) therapy, are not accessible or clinically appropriate, relies on the safety profile and sVNA titers of PEMGARDA demonstrated in the CANOPY Phase 3 clinical trial. Following the four cases of anaphylaxis seen in the CANOPY clinical trial, no reports of anaphylaxis have been identified to date during post-authorization use of PEMGARDA across potentially thousands of PEMGARDA doses administered in clinical practice. “Current therapies for COVID-19 have significant limitations, for example the drug-drug interaction complications imposed by nirmatrelvir create clinical circumstances in which standard of care may not be possible or appropriate for patients in need. Patients – particularly the millions of Americans who are immunocompromised – desperately need more and better therapeutic options because COVID-19 is not going away. Monoclonal antibodies have been highly attractive therapeutic options in the past and the community would welcome the return of a therapeutic mAb,” said Amesh Adalja, MD, FIDSA, FACP, FACEP, Senior Scholar, Johns Hopkins Center for Health Security. The EUA process does not rely on a statutory timeline such as the timelines embedded into the Prescription Drug User Fee Act (PDUFA)-based regulatory actions such as New Drug Application (NDA) or Biologics License Application (BLA) approval processes. Invivyd initially submitted a package to the FDA in support of a COVID-19 treatment EUA amendment request in July 2024, and since has provided consistent, timely updates to the FDA as SARS-CoV-2 virus variation has presented and as Invivyd has generated data in its ongoing industrial virology effort. Of note, given robust and consistent generation of sVNA titers, the direct expression of antibody antiviral activity, and comparability across multiple antibodies, Invivyd believes that the performance of Invivyd antibodies based on sVNA titers represents a well-supported surrogate endpoint and should be considered for approval beyond EUA to enable pemivibart to remain a long-term option for vulnerable, immunocompromised persons. About PEMGARDA PEMGARDA™ (pemivibart) is a half-life extended investigational monoclonal antibody (mAb). PEMGARDA was engineered from adintrevimab, Invivyd’s investigational mAb that has a robust safety data package and provided evidence of clinical efficacy in global Phase 2/3 clinical trials for the prevention and treatment of COVID-19. PEMGARDA has demonstrated in vitro neutralizing activity against major SARS-CoV-2 variants, including JN.1, KP.3.1.1 and XEC. PEMGARDA targets the SARS-CoV-2 spike protein receptor binding domain (RBD), thereby inhibiting virus attachment to the human ACE2 receptor on host cells. PEMGARDA (pemivibart) injection (4500 mg), for intravenous use is an investigational mAb that has not been approved, but has been authorized for emergency use by the U.S. FDA under an EUA for the pre-exposure prophylaxis (prevention) of COVID-19 in adults and adolescents (12 years of age and older weighing at least 40 kg) who have moderate-to-severe immune compromise due to certain medical conditions or receipt of certain immunosuppressive medications or treatments and are unlikely to mount an adequate immune response to COVID-19 vaccination. Recipients should not be currently infected with or have had a known recent exposure to an individual infected with SARS-CoV-2. PEMGARDA is not authorized for use for treatment of COVID-19 or post-exposure prophylaxis of COVID-19. Pre-exposure prophylaxis with PEMGARDA is not a substitute for vaccination in individuals for whom COVID-19 vaccination is recommended. Individuals for whom COVID-19 vaccination is recommended, including individuals with moderate-to-severe immune compromise who may derive benefit from COVID-19 vaccinations, should receive COVID-19 vaccination. In individuals who have recently received a COVID-19 vaccine, PEMGARDA should be administered at least 2 weeks after vaccination. Anaphylaxis has been observed with PEMGARDA and the PEMGARDA Fact Sheet for Healthcare Providers includes a boxed warning for anaphylaxis. The most common adverse events (all grades, incidence ≥2%) observed in participants who have moderate-to-severe immune compromise treated with PEMGARDA included systemic and local infusion-related or hypersensitivity reactions, upper respiratory tract infection, viral infection, influenza-like illness, fatigue, headache, and nausea. For additional information, please see the PEMGARDA full product Fact Sheet for Healthcare Providers, including important safety information and boxed warning. To support the EUA for PEMGARDA, an immunobridging approach was used to determine if PEMGARDA may be effective for pre-exposure prophylaxis of COVID-19. Immunobridging is based on the serum virus neutralizing titer-efficacy relationships identified with other neutralizing human mAbs against SARS-CoV-2. This includes adintrevimab, the parent mAb of pemivibart, and other mAbs that were previously authorized for EUA. There are limitations of the data supporting the benefits of PEMGARDA. Evidence of clinical efficacy for other neutralizing human mAbs against SARS-CoV-2 was based on different populations and SARS-CoV-2 variants that are no longer circulating. Further, the variability associated with cell-based EC50 value determinations, along with limitations related to pharmacokinetic data and efficacy estimates for the mAbs in prior clinical trials, impact the ability to precisely estimate protective titer ranges. Additionally, certain SARS-CoV-2 viral variants may emerge that have substantially reduced susceptibility to PEMGARDA, and PEMGARDA may not be effective at preventing COVID-19 caused by these SARS-CoV-2 viral variants. The emergency use of PEMGARDA is only authorized for the duration of the declaration that circumstances exist justifying the authorization of the emergency use of drugs and biological products during the COVID-19 pandemic under Section 564(b)(1) of the Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 360bbb-3(b)(1), unless the declaration is terminated or authorization revoked sooner. PEMGARDA is authorized for use only when the combined national frequency of variants with substantially reduced susceptibility to PEMGARDA is less than or equal to 90%, based on available information including variant susceptibility to PEMGARDA and national variant frequencies. About InvivydInvivyd, Inc. (Nasdaq: IVVD) is a biopharmaceutical company devoted to delivering protection from serious viral infectious diseases, beginning with SARS-CoV-2. Invivyd deploys a proprietary integrated technology platform unique in the industry designed to assess, monitor, develop, and adapt to create best in class antibodies. In March 2024, Invivyd received emergency use authorization (EUA) from the U.S. FDA for a monoclonal antibody (mAb) in its pipeline of innovative antibody candidates. Visit https://invivyd.com/ to learn more. Trademarks are the property of their respective owners. Cautionary Note Regarding Forward Looking StatementsThis press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as “anticipates,” “believes,” “could,” “expects,” “estimates,” “intends,” “potential,” “projects,” and “future” or similar expressions (as well as other words or expressions referencing future events, conditions or circumstances) are intended to identify forward-looking statements. Forward-looking statements include statements concerning, among other things, the company’s ongoing research and development activities, as well as future potential research and development efforts; the company’s emergency use authorization (EUA) amendment request for PEMGARDA™ (pemivibart) for the treatment of mild-to-moderate COVID-19 in certain immunocompromised patients, and the company’s beliefs regarding data supportive thereof; expectations regarding the duration of antiviral activity of pemivibart, and the potential benefits of pemivibart’s pharmacodynamic profile; the company’s intention to assess the virologic profile of pemivibart in a clinical study, if an EUA amendment for COVID-19 treatment is granted; expectations regarding the COVID-19 landscape, limitations of current therapies for COVID-19, and the potential of mAbs as a therapeutic option for COVID-19; the company’s beliefs about possible regulatory pathways for Invivyd antibodies, and the potential for pemivibart as a long-term option for vulnerable, immunocompromised patients; the company’s ongoing industrial virology effort; the potential of PEMGARDA as a mAb for pre-exposure prophylaxis (prevention) of COVID-19 in certain adults and adolescents who have moderate-to-severe immune compromise; the company’s devotion to delivering protection from serious viral infectious diseases, beginning with SARS-CoV-2; and other statements that are not historical fact. The company may not actually achieve the plans, intentions or expectations disclosed in the company’s forward-looking statements and you should not place undue reliance on the company’s forward-looking statements. These forward-looking statements involve risks and uncertainties that could cause the company’s actual results to differ materially from the results described in or implied by the forward-looking statements, including, without limitation: the outcome of the company’s EUA amendment request for pemivibart for treatment of mild-to-moderate COVID-19 in certain immunocompromised patients, and the timing thereof; how long the EUA granted by the FDA for PEMGARDA will remain in effect and whether the EUA is revised or revoked by the FDA; uncertainties related to the regulatory authorization or approval process, and available development and regulatory pathways for authorization or approval of the company’s product candidates; the ability to maintain a continued acceptable safety, tolerability and efficacy profile of any product candidate following regulatory authorization or approval; changes in the regulatory environment; the timing and progress of the company’s discovery, preclinical and clinical development activities; the risk that results of nonclinical studies or clinical trials may not be predictive of future results, and interim data are subject to further analysis; unexpected safety or efficacy data observed during preclinical studies or clinical trials; the predictability of clinical success of the company’s product candidates based on neutralizing activity in nonclinical studies; potential variability in neutralizing activity of product candidates tested in different assays, such as pseudovirus assays and authentic assays; the company’s reliance on third parties with respect to virus assay creation and product candidate testing and with respect to its clinical trials; variability of results in models and methods used to predict activity against SARS-CoV-2 variants; whether the epitope that pemivibart targets remains structurally intact; whether pemivibart or any other product candidate is able to demonstrate and sustain neutralizing activity against major SARS-CoV-2 variants, particularly in the face of viral evolution; the company’s ability to maintain and expand sales, marketing and distribution capabilities to successfully commercialize PEMGARDA; changes in expected or existing competition; the company’s ability to continue as a going concern; and whether the company has adequate funding to meet future operating expenses and capital expenditure requirements. Other factors that may cause the company’s actual results to differ materially from those expressed or implied in the forward-looking statements in this press release are described under the heading “Risk Factors” in the company’s Annual Report on Form 10-K for the year ended December 31, 2023 and the company’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2024, each filed with the Securities and Exchange Commission (SEC), and in the company’s other filings with the SEC, and in its future reports to be filed with the SEC and available at www.sec.gov. Forward-looking statements contained in this press release are made as of this date, and Invivyd undertakes no duty to update such information whether as a result of new information, future events or otherwise, except as required under applicable law. This press release contains hyperlinks to information that is not deemed to be incorporated by reference in this press release. Contacts: Media Relations(781) 208-1747media@invivyd.com Investor Relations(781) 208-1747investors@invivyd.com 1 Hammond et al NEJM 2022;386:1397-1408 2 Ison et al Open Forum Infect Dis. 2023 May 24;10(6):ofad279