Inovio Pharmaceuticals (United States)

To evaluate the long-term safety and clinical effect of INO-3107 immunotherapy in adults with recurrent respiratory papillomatosis (RRP). RRP-002 was a retrospective, observational extension study that followed patients enrolled in the 52-week RRP-001 study. Patients with moderate to severe juvenile or adult-onset RRP who had undergone ≥ 2 surgical interventions in the year preceding dosing were eligible for enrollment in RRP-001. Participants underwent surgical debulking within 14 days prior to initial dosing and then received INO-3107 on Day 0, Weeks 3, 6, and 9. Efficacy assessments during RRP-002 follow-up were the frequency of surgical interventions and alternative medication use. The safety evaluation included reported serious adverse events (SAEs). Twenty-eight (28) of 32 participants from the 52-week RRP-001 study were enrolled in RRP-002. The median follow-up time for RRP-002 was 1.8 years (range: 1.2-2.4 years) for a total median assessment time of 2.8 years (range: 1.0-3.5 years). There were no SAEs or long-term safety concerns identified. The mean number of surgeries was reduced from 4.1 in the pre-treatment period to 1.7 in the first year post-INO-3107 treatment (Year 1) to 0.9 in the second year (Year 2). The complete response rate (0 surgeries per year) increased from 28% (9/32) in Year 1 to 50% (14/28) in Year 2. INO-3107 is well tolerated and provides a continued clinical effect against HPV-6 and 11 RRP that results in further reduction of the surgical burden observed in Year 1. These data support the role of INO-3107 immunotherapy for adult patients with RRP. III.

Abstract Local intramuscular administration of synthetic plasmid DNA (pDNA) encoding monoclonal antibodies (mAb) represents an alternative approach to recombinant protein technology. In this Phase 1, dose escalation study (NCT05293249), we administered a pDNA cocktail encoding AZD5396 and AZD8076, modified versions of the SARS-CoV-2 neutralizing mAb cocktail Evusheld™, by CELLECTRA™ in vivo electroporation technology to healthy adults. Primary endpoints of this study were safety and pharmacokinetics of the in vivo expressed DNA-encoded mAbs (DMAbs). Muscle-expressed DMAbs were detected in the serum of all dosed subjects (N=39), with concentrations reaching 1.39 µg/ml. Remarkably consistent levels of serum DMAbs were measured for at least 72 weeks post-administration in 24/24 subjects who have reached this time point. DMAbs isolated from serum demonstrated SARS-CoV-2 RBD binding and neutralization activity in a standard pseudovirus assay. While the study is ongoing, we have not detected anti-drug antibodies in any of the trial participants thus far. These data represent the first clinical proof-of-concept that synthetic pDNA DMAb technology permits the durable in vivo production of a functional mAb cocktail. This study further underscores the collective importance of synthetic design, formulation, and delivery to achieve biologically relevant expression of gene-encoded biologics. DMAb delivery may represent a valuable strategy against a wide range of diseases which can be targeted with mAbs and their derivatives.

The urgency and importance of organizing a global effort to harmonize clinical assay validation specific to the vaccine industry was identified during the drafting of the 2020 White Paper in Bioanalysis due to the lack of clarity and regulatory guidance/guidelines in vaccine immunoassay validation. Indeed, the Workshop on Recent Issues in Bioanalysis (WRIB) issues the White Paper in Bioanalysis yearly, which is one of the high-profile articles of the Bioanalysis Journal focused on detailed discussions and recommendations on vaccine assay validation. Since 2017, participation in the WRIB working groups by vaccine assay validation experts and regulators has rapidly increased due to its unique format where industry leaders and regulators can meet and exchange ideas on topics of interest to both groups. In early 2021, Vaccine manufacturers approached WRIB for sponsoring/supporting the authorship and publication of an overarching vaccine assay validation document based on the 2017-2020 discussions and consensus starting from immunogenicity assays first and followed by future papers on molecular and cell-based assay validation. Using industry and WRIB vaccine network, a vaccine immunogenicity assay validation working group was assembled consisting of 16 companies. The work on the first white paper started officially in April 2021 focusing on Vaccine LBA Validation (Part 1), and the drafting of Vaccine LBA Development (Part 2) and Vaccine LBA Monitoring & Transfer (Part 3) are presently ongoing and expected to be published shortly after this paper. Moreover, recommendations on Vaccine Cell-Based Assays Validation (ELISpot and Flow cytometry) and Vaccine Molecular Assays Validation (PCR, NGS, NanoString) are also on the WRIB publications agenda and the drafting is planned to start in mid-2024. For too long, vaccine scientists have not had a clear validation guidance for clinical vaccine immunogenicity assays. We hope that this common effort will help close this regulatory gap.

Purpose:Tumoral programmed cell death ligand-1 (PD-L1) expression is common in human papillomavirus (HPV)–associated head and neck squamous cell carcinoma (HNSCC). We assessed whether a DNA vaccine targeting HPV-16/18 E6/E7 with IL12 adjuvant (MEDI0457) combined with the PD-L1 inhibitor durvalumab could enhance HPV-specific T-cell response and improve outcomes in recurrent/metastatic HPV-16/18–associated HNSCC.Patients and Methods:In this phase Ib/IIa study, immunotherapy-naïve patients with ≥1 previous platinum-containing regimen (neoadjuvant/adjuvant therapy or for recurrent/metastatic disease) received MEDI0457 7 mg intramuscularly with electroporation on weeks 1, 3, 7, and 12, then every 8 weeks, plus durvalumab 1,500 mg intravenously on weeks 4, 8, and 12, then every 4 weeks, until confirmed progression and/or unacceptable toxicity. Coprimary objectives were safety and objective response rate (ORR; H0: ORR ≤ 15%); secondary objectives included 16-week disease control rate (DCR-16), overall survival (OS), and progression-free survival (PFS).Results:Of 35 treated patients, 29 were response evaluable (confirmed HPV-associated disease; received both agents). ORR was 27.6% [95% confidence interval (CI), 12.7–47.2; four complete responses, four partial responses]; responses were independent of PD-L1 tumor-cell expression (≥25% vs. <25%). DCR-16 was 44.8% (95% CI, 26.5–64.3). Median PFS was 3.5 months (95% CI, 1.9–9.0); median OS was 29.2 months (15.2–not calculable). Twenty-eight (80.0%) patients had treatment-related adverse events [grade 3: 5 (14.3%); no grade 4/5], resulting in discontinuation in 2 (5.7%) patients. HPV-16/18–specific T cells increased on treatment; 4 of 8 evaluable patients had a >2-fold increase in tumor-infiltrating CD8+ T cells.Conclusions:MEDI0457 plus durvalumab was well tolerated. While the primary efficacy endpoint was not reached, clinical benefit was encouraging.

Nipah virus (NiV) is a re-emerging pathogen that causes severe disease in animals and humans. Current treatment measures for NiV infection are insufficient, and there is no approved vaccine against NiV for either humans or animals. Nipah virus is listed as a high-priority pathogen for vaccine and therapeutic research by the World Health Organization (WHO). In the present study, we employed synthetic enhanced DNA technologies developed to design and produce novel consensus NiV Fusion (NiV-F) and Glycoprotein (NiV-G) antigen sequences for inclusion in synthetic DNA vaccines for NiV. The expression of each vaccine antigen was confirmed in vitro using immune-binding assays. Electroporation-enhanced intramuscular injection of each NiV-F and NiV-G into mice induced potent cellular immune responses to multiple epitopes of NiV-G and NiV-F that included antigen-specific CD8+ T cells. Both vaccines elicited high antibody titers in mice, with a single immunization sufficient to seroconvert 100% of immunized animals. Additionally, the NiV-F vaccine also induced antibodies to neutralize NiV-F-pseudotyped virus particles. These data support further study of these novel synthetic enhanced NiV nucleic acid-based antigens as potential components of an effective vaccine against the Nipah virus.

Novel approaches for malaria prophylaxis remain important. Synthetic DNA-encoded monoclonal antibodies (DMAbs) are a promising approach to generate rapid, direct in vivo host-generated mAbs with potential benefits in production simplicity and distribution coupled with genetic engineering. Here, we explore this approach in a malaria challenge model. We engineered germline-reverted DMAbs based on human mAb clones CIS43, 317, and L9 which target a junctional epitope, major repeat, and minor repeat of the Plasmodium falciparum circumsporozoite protein (CSP) respectively. DMAb variants were encoded into a plasmid vector backbone and their expression and binding profiles were characterized. We demonstrate long-term serological expression of DMAb constructs resulting in in vivo efficacy of CIS43 GL and 317 GL in a rigorous mosquito bite mouse challenge model. Additionally, we engineered an Fc modified variant of CIS43 and L9-based DMAbs to ablate binding to C1q to test the impact of complement-dependent Fc function on challenge outcomes. Complement knockout variant DMAbs demonstrated similar protection to that of WT Fc DMAbs supporting the notion that direct binding to the parasite is sufficient for the protection observed. Further investigation of DMAbs for malaria prophylaxis appears of importance.

BackgroundAdditional SARS-CoV-2 vaccines that are safe and effective as primary vaccines and boosters remain urgently needed to combat the COVID-19 pandemic. We describe the safety and durability of the immune responses following two primary doses and a homologous booster dose of an investigational DNA vaccine (INO-4800) targeting the full-length spike antigen.MethodsThree dosage strengths of INO-4800 (0.5 mg, 1.0 mg, and 2.0 mg) were evaluated in 120 age-stratified healthy adults. Intradermal injection of INO-4800 followed by electroporation at 0 and 4 weeks preceded an optional booster 6-10.5 months after the second dose.ResultsINO-4800 appeared well tolerated, with no treatment-related serious adverse events. Most adverse events were mild and did not increase in frequency with age and subsequent dosing. A durable antibody response was observed 6 months following the second dose; a homologous booster dose significantly increased immune responses. Cytokine producing T cells and activated CD8+ T cells with lytic potential were significantly increased in the 2.0 mg dose group.ConclusionINO-4800 was well tolerated in a 2-dose primary series and as a homologous booster in all adults, including the elderly. These results support further development of INO-4800 for use as a primary vaccine and as a booster.

SummaryCoronavirus disease 2019 (COVID-19), caused by the SARS-CoV-2 virus, has had a dramatic global impact on public health and social and economic infrastructures. Here, we assess the immunogenicity and anamnestic protective efficacy in rhesus macaques of an intradermal (i.d.)-delivered SARS-CoV-2 spike DNA vaccine, INO-4800, currently being evaluated in clinical trials. Vaccination with INO-4800 induced T cell responses and induced spike antigen and RBD binding antibodies with ADCP and ADCD activity. Sera from the animals neutralized both the D614 and G614 SARS-CoV-2 pseudotype viruses. Several months after vaccination, animals were challenged with SARS-CoV-2 resulting in rapid recall of anti-SARS-CoV-2 spike protein T cell and neutralizing antibody responses. These responses were associated with lower viral loads in the lung. These studies support the immune impact of INO-4800 for inducing both humoral and cellular arms of the adaptive immune system, which are likely important for providing durable protection against COVID-19 disease.

Abstract Safe and effective vaccines will provide essential medical countermeasures to tackle the COVID-19 pandemic. Here, we evaluate the safety, immunogenicity and efficacy of the intradermal delivery of INO-4800, a synthetic DNA vaccine candidate encoding the SARS-CoV-2 spike protein in the rhesus macaque model. Single and 2 dose vaccination regimens were evaluated. Vaccination induces both binding and neutralizing antibodies, along with IFN-γ-producing T cells against SARS-CoV-2. Upon administration of a high viral dose (5 x 106 pfu) via the intranasal and intratracheal routes we observe significantly reduced virus load in the lung and throat, in the vaccinated animals compared to controls. 2 doses of INO-4800 is associated with more robust vaccine-induced immune responses and improved viral protection. Importantly, histopathological examination of lung tissue provides no indication of vaccine-enhanced disease following SARS-CoV-2 challenge in INO-4800 immunized animals. This vaccine candidate is currently under clinical evaluation as a 2 dose regimen.

Hyperammonemia is a dangerous life-threatening metabolic complication characterized by markedly elevated ammonia levels that can lead to irreversible brain damage if not carefully monitored. Current pharmacological treatment strategies available for hyperammonemia patients are suboptimal and associated with major side effects. In this study, we focus on developing and evaluating the in vivo delivery of novel DNA-encoded glutamine synthetase (GS) enzymes for the treatment of hyperammonemia. Direct in vivo delivered DNA-encoded GS enzyme was evaluated in ammonium acetate-induced hyperammonemia and thioacetamide-induced acute liver injury (ALI) models in C57BL/6 mice. In ammonium acetate-induced hyperammonemia model, we achieved a 30.5% decrease in blood ammonia levels 15 min postadministration of ammonium acetate, with DNA-encoded GS-treated group. Significant increase in survival was observed in ALI model with the treated mice. A comparison of the secreted versus intracellular DNA-encoded GS enzyme demonstrated similar increases in survival in the ALI model, with 40% mortality in the secreted enzymes and 30% mortality in the intracellular enzymes, as compared with 90% mortality in the control group. Direct in vivo delivery of DNA-encoded GS demonstrated important ammonia-lowering potential. These results provide the initial steps toward development of delivered DNA as a potential new approach to ammonia-lowering therapeutics.