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KANAZAWA, Japan, Jan. 10, 2024 /PRNewswire/ -- Researchers at Nano Life Science Institute (WPI-NanoLSI), Kanazawa University report in Nano Letters how the flexibility of a protein hinge plays a crucial role in the transfer of proteins in key cell processes. Ubiquitination – the addition of the protein ubiquitin - is a key stage in many cell processes, such as protein degradation, DNA repairs, and signal transduction. Using high-speed atomic force microscopy (HS-AFM) and molecular modelling, researchers led by Hiroki Konno and Holger Flechsig at WPI-NanoLSI, Kanazawa University have identified how the mobility of a ubiquitination related enzyme hinge allows ubiquitination to take place. Previous studies have identified a number of enzymes that facilitate ubiquitination, including an enzyme that activates ubiquitin (E1), an enzyme that conjugates it (E2), and an enzyme that catalyzes ubiquitin protein joining (i.e. a ligase, E3) to target protein (Fig. 1). The HECT-type E3 ligase is characterized by a HECT domain that comprises an N lobe with the E2-binding site and a C lobe with a catalytic Cys residue, a flexible hinge connects the two lobes, leading to the hypothesis that ubiquitination is facilitated by the rearrangement of the protein around this hinge. Konno and their collaborators deployed their high-speed atomic force microscope to hunt for evidence that this was the case. The researchers noted that when the HECT domain was crystallized with a type of E2 enzyme, it formed an L shape such that the distance between the catalytic Cys residue of the HECT domain and the catalytic Cys of the E2 enzyme was 41 Å – too far for the transfer of ubiquitin. However, in its catalytic conformation the HECT domain has a different shape where the distance between the two catalytic Cys residues is much closer – just 8 Å – so this is thought to be a 'catalytic conformation'. Analysis of HS-AFM images of a wild-type HECT domain of E6AP revealed two conformations – one of which looked spherical and the other oval (Fig. 2). Using AFM simulations they attributed the oval shapes to the L conformation and spherical shapes are either the catalytic conformation or the so called inverted T conformation, which had been observed in the another type of HECT domain where the distance between the Cys residues is 16 Å (Fig. 2). To overcome the spatio-temporal resolution limitations of imaging, the experiments were complemented by molecular modelling to visualize HECT domain conformational motions at the atomistic level. Simulation AFM was used to generate a corresponding pseudo AFM movie, which clearly showed the change from spherical to the oval shaped topography (Fig. 2). "Although experimental limitations do not allow us to resolve the intermediate conformations," explain the researchers in their report of the work. "The performed modeling provides evidence that the transitions between spherical and oval HECT domain shapes observed under HS-AFM correspond to functional conformational motions under which the C-lobe rotates relative to the N-lobe, thereby allowing the change between catalytic and L-shape HECT conformations." Further experiments with mutant HECT domains with less flexibility in the hinge revealed no flipping between conformations – the mutant HECT domains were locked in the catalytic conformation. They also found that while these mutant HECT domains could form two ubiquitin proteins joined together more efficiently than the wild type. E6AP, the HECT-type E3 in this study, interacts with E6 protein derived from human papillomavirus (HPV) and ubiquitinates p53, a tumor suppressor protein. It is also known that ubiquitination of p53 by E6AP and E6 is a major cause of cervical cancer. However, the mechanism of p53 ubiquitination by the interaction of E6AP and E6 proteins remains unclear. In the future, we will elucidate the structural dynamics of E6AP/E6, and the E6AP/E6/p53 complex with HS-AFM, and clarify how E6 increases the activity of p53 ubiquitination by E6AP. Figure 1 link: Fig 1 caption: Ubiquitination and degradation of protein by the ubiquitin-proteasome system. © 2023 Takeda, et al., Published by American Chemical Society Fig. 2 link: Fig 2 caption: High-speed AFM observation and simulation of the structural dynamics of the HECT domain of E6AP. (A) HS-AFM image of the HECT domain. Spherical (white dotted line) and oval (blue dotted line) conformational states were observed. (B) Simulated transition process of the structural state of the HECT domain and its pseudo AFM image. (C) Ubiquitin (Ub) is transferred from E2 to E3 (HECT domain). After the addition of ubiquitin-containing E2 (E2-Ub), E2-Ub (white arrow) binds to the HECT domain, and after E2 dissociates, a small particle (blue arrow) that appears to be ubiquitin is added to the HECT domain. © 2023 Takeda, et al., Published by American Chemical Society Glossary Ubiquitin The protein takes its name from the term 'ubiquitous' because it is found in almost all tissues. It can be added as a single protein or further proteins added into a chain. This 'ubiquitination' is an essential step in many cell processes. High-speed atomic force microscopy This imaging technique uses a nanosized tip at the end of a cantilever that is scanned over a sample. It can be used to determine the topography of a sample surface from the change in the strength of forces between the tip and the sample with distance, and the resulting deflection of the cantilever. It was first developed in the 1980s but a number of modifications have augmented the functionality of the technique since. It is better suited to imaging biological samples than the scanning tunnelling microscope developed that had been developed because it does not require a conducting sample. In the 2000s Toshio Ando at Kanazawa University was able to improve the scanning speed to such an extent that moving images could be captured. This allowed people to use the technique to visualize molecular processes for the first time. Reference Kazusa Takeda†, Holger Flechsig†, Ikumi Muro†, Romain Amyot, Fuminori Kobayashi, Noriyuki Kodera, Toshio Ando and Hiroki Konno, Structural Dynamics of E6AP E3 Ligase HECT Domain and Involvement of a Flexible Hinge Loop in the Ubiquitin Chain Synthesis Mechanism, Nano Letters, 2023, 23, 24, 11940–11948. †These authors contributed equally to this work DOI：10.1021/acs.nanolett.3c04150 URL: Contact Hiroe Yoneda Senior Specialist in Project Planning and Outreach NanoLSI Administration OfficeNano Life Science Institute (WPI-NanoLSI) Kanazawa University Kakuma-machi, Kanazawa 920-1192, Japan Email: [email protected] Tel: +81 (76) 234-4555 About Nano Life Science Institute (WPI-NanoLSI), Kanazawa University Understanding nanoscale mechanisms of life phenomena by exploring 'uncharted nano-realms'. Cells are the basic units of almost all life forms. We are developing nanoprobe technologies that allow direct imaging, analysis, and manipulation of the behavior and dynamics of important macromolecules in living organisms, such as proteins and nucleic acids, at the surface and interior of cells. We aim at acquiring a fundamental understanding of the various life phenomena at the nanoscale. About the World Premier International Research Center Initiative (WPI) The WPI program was launched in 2007 by Japan's Ministry of Education, Culture, Sports, Science and Technology (MEXT) to foster globally visible research centers boasting the highest standards and outstanding research environments. Numbering more than a dozen and operating at institutions throughout the country, these centers are given a high degree of autonomy, allowing them to engage in innovative modes of management and research. The program is administered by the Japan Society for the Promotion of Science (JSPS). About Kanazawa University As the leading comprehensive university on the Sea of Japan coast, Kanazawa University has contributed greatly to higher education and academic research in Japan since it was founded in 1949. The University has three colleges and 17 schools offering courses in subjects that include medicine, computer engineering, and humanities. The University is located on the coast of the Sea of Japan in Kanazawa – a city rich in history and culture. The city of Kanazawa has a highly respected intellectual profile since the time of the fiefdom (1598-1867). Kanazawa University is divided into two main campuses: Kakuma and Takaramachi for its approximately 10,200 students including 600 from overseas. SOURCE Kanazawa University

42 percent objective response rate (ORR) was observed among 19 evaluable patients with recurrent/metastatic head and neck cancer in the first-line setting—doubling historical ORR reported with pembrolizumab alone1 Strong immunogenicity and activation of antigen-specific CD8+ T cells observed Data reinforce HOOKIPA’s commitment to start a randomized trial of HB-200 in combination with pembrolizumab as 1st-line treatment of recurrent/metastatic HPV16+ head and neck cancer in 2024 Data presented at the European Society for Medical Oncology Congress 2023 NEW YORK and VIENNA, Austria, Oct. 22, 2023 (GLOBE NEWSWIRE) -- HOOKIPA Pharma Inc. (NASDAQ: HOOK, ‘HOOKIPA’), a company developing a new class of immunotherapeutics based on its proprietary arenavirus platform, today presented updated data from its ongoing Phase 2 trial of HB-200 in combination with pembrolizumab in patients with recurrent/metastatic Human Papillomavirus 16-positive (HPV16+) head and neck cancer. The preliminary data presented at the European Society for Medical Oncology (ESMO) Congress 2023 showed a 42 percent confirmed objective response rate (ORR) and disease control rate (DCR) of 74 percent across 19 evaluable patients treated with HB-200 in combination with pembrolizumab in the 1st-line, checkpoint inhibitor (CPI)-naïve setting, doubling the 19 percent ORR for pembrolizumab alone1. Best overall response for the evaluable population included one patient with a confirmed complete response, seven patients with confirmed partial responses, and six patients with stable disease. All evaluable patients were alive at the data cutoff (DCO), and the median follow-up time at DCO was 8.3 months. Median overall survival and progression-free survival data are still maturing. Importantly, results showed significant activation of antigen-specific CD8+ T cells, the body’s primary driver of tumor killing activity. Out of 17 patients with available peripheral blood mononuclear cells (PMBC) samples, all patients showed an increase of tumor antigen-specific circulating HPV16+ CD8+ T cells. These T cell activation data are consistent with previously reported monotherapy data for HB-200. “We have observed objective response rate, disease control rate, and activation of antigen-specific T cells which demonstrate the potential of the intended mechanism to stimulate the immune system to combat tumors. We have also observed generally favorable tolerability to date among the patient population, supporting the investigational therapy’s potential in combination settings,” said Dr. Alan L. Ho, Head and Neck Oncologist at Memorial Sloan Kettering Cancer Center and a trial investigator. “We continue to see encouraging results in the first-line patient setting for our HB-200 trial in combination with pembrolizumab as we have consistently observed patient responses that are double the ORR observed in standard of care treatments alone—reinforcing previously reported data,” said Joern Aldag, Chief Executive Officer at HOOKIPA. “These results give us great conviction to proceed with our planned randomized trial.” Results: HB-200 in combination with pembrolizumab in the 1st-line setting (NCT04180215)As of the DCO, August 7, 2023, the updated interim efficacy analysis included 19 evaluable patients with at least two imaging assessments out of the first 20 patients with HPV16+ recurrent/metastatic head and neck cancers treated with HB-200 in combination with pembrolizumab in the 1st-line setting as part of the Phase 2 trial. Of the intent-to-treat population (n=20) one patient was not evaluable due to COVID-related death prior to the first tumor scan. All patients received HB-200 intravenously every three weeks for the first five doses and every six weeks thereafter. HB-200 is a 2-vector investigational therapy with alternating administration of Lymphocytic Choriomeningitis Virus (LCMV), and Pichinde Virus (PICV) vectors, encoding the same HPV16 E6/E7 antigens. HB-200 in combination with pembrolizumab demonstrated promising initial anti-tumor activity with a 42 percent ORR (8 of 19 evaluable patients with confirmed responses by investigator assessment under RECIST 1.1) among CPI-naïve patients with 1st-line recurrent/metastatic HPV16+ PD-L1+ head and neck cancer. These data represent a doubling of the 19 percent ORR reported for pembrolizumab alone1 and are consistent with previously reported HB-200 data. Eight patients responded including one with a confirmed complete response and seven with confirmed partial responses. Another six patients achieved stable disease representing a DCR of 74 percent (14 of 19 patients). While recruitment is ongoing, based on these data, HOOKIPA is preparing to start a randomized trial of HB-200 in combination with pembrolizumab as 1st-line treatment of recurrent/metastatic HPV16+ PD-L1+ head and neck cancers in 2024. ImmunogenicityTumor-specific CD8+ T cell levels induced by HB-200 in combination with pembrolizumab are unprecedented and consistent with levels observed with HB-200 monotherapy. Among the 17 patients with available peripheral blood mononuclear cells (PMBC) samples, all patients showed an increase in the percent of tumor antigen-specific circulating HPV16+ CD8+ T cell responses per intercellular cytokine staining analysis. Peak percentage of antigen-specific circulating HPV16+ CD8+ T cell responses reached up to 31 percent with a median of 3.36 percent. Max response on treatment vs. before treatment of systemic HPV-16 E7 and E6 specific T cells measured by ELISPOT showed that the median fold-increase for these patients’ total tumor specific T cells was a 451-fold increase over baseline, with the maximal increase of 4,000-fold. Safety and tolerability profileResults from the HB-200 in combination with pembrolizumab in 1st-line patients arm of the Phase 2 part of the trial showed that HB-200 was generally well tolerated among 20 patients treated. Two patients (10 percent) showed serious adverse events related to the treatment with HB-200 or pembrolizumab. Only one patient (5 percent) discontinued due to a treatment-related adverse event (related to pembrolizumab). The updated safety profile adds to the previously reported safety and tolerability data from all 132 patients across all arms of the trial who received HB-200 monotherapy or HB-200 in combination with pembrolizumab. This generally favorable tolerability profile highlights the potential of HB-200—and arenaviral immunotherapies in general—to be successfully combined with other immunotherapies where tumor antigen-specific T cell induction is of potential benefit. ESMO HB-200 Poster Presentation Title: HB-200 Arenavirus-Based Immunotherapy Plus Pembrolizumab as a First-Line Treatment in Patients with Recurrent/Metastatic HPV16-Positive Head and Neck CancerPresenter: Dr. Alan L. Ho, Head and Neck Oncologist at Memorial Sloan Kettering Cancer Center and a trial investigatorSession Date: October 22, 2023Poster Board Number: 921PAbstract Number: 2212 About HB-200HB-200 is HOOKIPA’s lead oncology candidate engineered with the company’s proprietary replicating arenaviral vector platform. HB-200 is an alternating 2-vector immunotherapy designed to focus the immune response against the encoded antigen. It comprises two single-vector compounds with arenaviral backbones based on LCMV and PICV. Both encode and express an identical E7E6 fusion protein, comprising well characterized tumor-specific antigens for HPV16+ cancers. HB-200 in combination with pembrolizumab received Fast Track Designation from the U.S. Food and Drug Administration for the treatment of 1st-line recurrent/metastatic HPV16+ head and neck cancers. About the HB-200 trial (NCT04180215)This Phase 1/2 clinical trial is an open-label trial evaluating HB-200 for the treatment of advanced HPV16+ cancers. Phase 1 assessed various dose levels, regimen, and modes of administration in a post-standard of care setting. Based on safety and tolerability, initial anti-tumor activity and T cell response data, HB-200 was advanced for further development in Phase 2. The Phase 2 part of the trial is open label with primary endpoints of efficacy based on objective response and disease control rate as defined by RECIST 1.1 and iRECIST. The trial is evaluating HB-200 in combination with pembrolizumab in the 1st-line and 2nd-line plus settings, as well as HB-200 alone in the post-standard of care setting. About Human Papillomavirus-driven CancersHuman Papillomavirus, or HPV, is a common viral infection estimated to cause about 5 percent of the worldwide cancer burden. This includes up to 60 percent of head and neck, 89 percent of cervical, 78 percent of vaginal, 88 percent of anal, 67 percent of vulvar and 50 percent of penile cancers. While there are numerous HPV types associated with cancer, HPV16 is the most common cause of cancer. Most HPV infections are cleared from the body with no lasting consequences. However, in some cases, HPV DNA becomes integrated into chromosomal DNA. When host cells take up this DNA, they express the HPV E6 and E7 proteins. This uptake can potentially lead to cancer since expression of these proteins leads to alterations in cell cycle control, which in turn predisposes these cells to become cancerous. About HOOKIPAHOOKIPA Pharma Inc. (NASDAQ: HOOK) is a clinical-stage biopharmaceutical company focused on developing novel immunotherapies, based on its proprietary arenavirus platform, which are designed to mobilize and amplify targeted T cells and thereby fight or prevent serious disease. HOOKIPA’s replicating and non-replicating technologies are engineered to induce robust and durable antigen-specific CD8+ T cell responses and pathogen-neutralizing antibodies. HOOKIPA’s pipeline includes its wholly owned investigational arenaviral immunotherapies targeting Human Papillomavirus 16-positive cancers, prostate cancers, and other undisclosed programs. HOOKIPA is collaborating with Roche on an arenaviral immunotherapeutic for KRAS-mutated cancers. In addition, HOOKIPA aims to develop functional cures of HBV and HIV in collaboration with Gilead. Find out more about HOOKIPA online at www.hookipapharma.com. 1 Harrington et al. Pembrolizumab With or Without Chemotherapy in Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma: Updated Results of the Phase III KEYNOTE-048 Study. Journal of Clinical Oncology. 2023;41(4);790-802. Forward Looking StatementsCertain statements set forth in this press release constitute “forward-looking” statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended. Forward-looking statements can be identified by terms such as “believes,” “expects,” “plans,” “potential,” “would” or similar expressions and the negative of those terms. Such forward-looking statements involve substantial risks and uncertainties that could cause HOOKIPA’s research and clinical development programs, future results, performance or achievements to differ significantly from those expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, the uncertainties inherent in the drug development process, including HOOKIPA’s programs’ early stage of development, the process of designing and conducting preclinical and clinical trials, the risk that interim or preliminary data may differ from final data from clinical trials, the regulatory approval processes, the timing of regulatory filings, the challenges associated with manufacturing drug products, HOOKIPA’s ability to successfully establish, protect and defend its intellectual property, risks relating to business interruptions resulting from public health crises, the impact of public health crises on the enrollment of patients and timing of clinical results, and other matters that could affect the sufficiency of existing cash to fund operations. HOOKIPA undertakes no obligation to update or revise any forward-looking statements. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to the business of the company in general, see HOOKIPA’s quarterly report on Form 10-Q for the quarter ended June 30, 2023, which is available on the SEC’s website at www.sec.gov and HOOKIPA’s website at www.hookipapharma.com. Investors and others should note that we announce material financial information to our investors using our investor relations website (https://ir.hookipapharma.com/), SEC filings, press releases, public conference calls and webcasts. We use these channels, as well as social media, to communicate with our members and the public about our company, our services and other issues. It is possible that the information we post on social media could be deemed to be material information. Therefore, we encourage investors, the media, and others interested in our company to review the information we post on the U.S. social media channels listed on our investor relations website. For further information, please contact: MediaInvestorsInstinctif PartnersMichael Kaiser, Investor Relationshookipa@instinctif.com michael.kaiser@hookipapharma.com +44 (0) 7457 2020+1 (917) 984-7537

TG4001 can induce de novo immune responses against HPV16 antigens E6 and E7 in patients with advanced HPV16-positive anogenital cancers Patients with complete objective response showed strong vaccine-induced immunoreactivity Transgene is preparing for a potentially registrational study STRASBOURG, France I June 05, 2023 I Transgene (Euronext Paris: TNG), a biotech company that designs and develops virus-based immunotherapies for the treatment of cancer, announced that new data will be presented today on TG4001. These data confirm the ability of this novel investigational therapeutic cancer vaccine to induce immune responses against HPV16 antigens, that are associated with anti-tumor response. These results have been presented in a poster at the ongoing American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, IL. TG4001 is an investigational viral vector based therapeutic cancer vaccine. It is being evaluated in a randomized controlled Phase II clinical study comparing TG4001 in combination with avelumab to avelumab alone in patients with HPV16-positive anogenital tumors ( NCT: 03260023 ). The data presented at ASCO were generated from 46 patients included in both arms of the trial. TG4001 induced the priming of adaptive immunity 58% of patients receiving TG4001 + avelumab showed an increase of immune responses against HPV antigens versus 9% in the avelumab arm. At baseline, immune responses against HPV antigens were limited to 4/46 patients. The occurrence of an immune response was detected at day 43 and tended to gain in intensity at day 85. These data clearly demonstrate that Transgene’s TG4001 could induce a specific immune response against the antigens vectorized within this vaccine. 11 of the 13 patients with an immune response had either stable disease, partial or complete tumor response according to RECIST criteria. Remarkably, two case studies are presented, with patients exhibiting a strong E6 and E7 immune response while showing a complete clinical response . Preparing for a planned potentially registrational trial in an HPV-positive indication Transgene anticipates that the last patient will be randomized in the current Phase II clinical study in the first half of 2024. Final results will be communicated in 2024 . Transgene is working on the design of a potentially registrational trial to further confirm the benefit of this novel investigational therapeutic cancer vaccine. Dr Alessandro Riva, MD, Chairman and CEO of Transgene , added: “We are very excited by the immunological data that we are presenting at ASCO. These data further confirm that our therapeutic vaccine TG4001 can induce clinically meaningful immune responses, that are associated with antitumor response. We look forward to the final analysis of the ongoing randomized phase 2 study and the potential next steps for TG4001 in patients with HPV positive cancers”. The abstract and poster can be accessed on the ASCO and Transgene websites. About TG4001 TG4001 is an investigational therapeutic vaccine based on a non-propagative, highly attenuated Vaccinia vector (MVA), which is engineered to express HPV16 antigens (E6 & E7) and an adjuvant (IL-2). TG4001 is designed to have a two-pronged antiviral approach: to alert the immune system specifically to cells presenting the HPV16 E6 and E7 antigens, that can be found in HPV16-related tumors, and to further stimulate the infection-clearing activity of the immune system through interleukin 2 (IL-2). TG4001 has been administered to more than 350 individuals, demonstrating good safety and promising efficacy results [1] . Its mechanism of action and good safety profile make TG4001 an excellent candidate for combinations with other therapies in HPV-mediated solid tumors. It is currently evaluated in a multi-center, open label, randomized Phase II trial (NCT03260023) designed to compare the efficacy of the combination of TG4001 and avelumab versus avelumab alone in patients with advanced, recurrent and/or metastatic HPV16-positive anogenital cancers who have disease progression after a maximum of one line of systemic treatment, or who are not eligible for first-line chemotherapy. About Transgene Transgene (Euronext: TNG) is a biotechnology company focused on designing and developing targeted immunotherapies for the treatment of cancer. Transgene’s programs utilize viral vector technology with the goal of indirectly or directly killing cancer cells. The Company’s clinical-stage programs consist of a portfolio of therapeutic vaccines and oncolytic viruses: TG4050, the first individualized therapeutic vaccine based on the myvac ® platform, TG4001 for the treatment of HPV-positive cancers, as well as TG6002, BT-001 and TG6050, three oncolytic viruses based on the Invir.IO® viral backbone. With Transgene’s myvac ® platform, therapeutic vaccination enters the field of precision medicine with a novel immunotherapy that is fully tailored to each individual. The myvac ® approach allows the generation of a virus-based immunotherapy that encodes patient-specific mutations identified and selected by Artificial Intelligence capabilities provided by its partner NEC. With its proprietary platform Invir.IO®, Transgene is building on its viral vector engineering expertise to design a new generation of multifunctional oncolytic viruses. Additional information about Transgene is available at: www.transgene.fr SOURCE: Transgene