Imunon, Inc.

Imunon’s vaccine candidate comprises a single plasmid vector containing the DNA sequence encoding multiple SARS-CoV-2 antigens. Delivery will be evaluated intramuscularly, intradermally, or subcutaneously with a non-viral synthetic DNA delivery carrier that facilitates vector delivery into the cells of the injected tissue and has potential immune adjuvant properties. Unique designs and formulations of Imunon vaccine candidates may offer several potential key advantages. The synthetic polymeric DNA carrier is an important component of the vaccine composition as it has the potential to facilitate the vaccine immunogenicity by improving vector delivery and, due to potential adjuvant properties, attract professional immune cells to the site of vaccine delivery.

Future vaccine technology will need to address viral mutations and the challenges of efficient manufacturing, distribution, and storage. We believe the adaptation of our TheraPlas technology, PLACCINE, has the potential to meet these challenges. Our approach is summarized as a DNA vaccine technology platform characterized by a single plasmid DNA with multiple coding regions. The plasmid vector is designed to express multiple pathogen antigens. It is delivered via a synthetic delivery system and has the potential to be easily modified to create vaccines against a multitude of infectious diseases, addressing:

On September 2, 2021, the Company announced results from preclinicalin vivo studies showing production of antibodies and cytotoxic T-cell response specific to the spike antigen of SARS-CoV-2 when immunizing BALB/c mice with the Company’s next-generation PLACCINE DNA vaccine platform. Moreover, the antibodies to SARS-CoV-2 spike antigen prevented the infection of cultured cells in a viral neutralization assay. The production of antibodies predicts the ability of PLACCINE to protect against SARS-CoV-2 exposure, and the elicitation of cytotoxic T-cell response shows the vaccine’s potential to eradicate cells infected with SARS-CoV-2. These findings demonstrated the potential immunogenicity of Imunon’s PLACCINE DNA vaccine, which is intended to provide broad-spectrum protection and resistance against variants by incorporating multiple viral antigens, to improve vaccine stability at storage temperatures of 4°C and above, and to facilitate cheaper and easier manufacturing.

On January 31, 2022, the Company announced the initiation of a nonhuman primate (“NHP”) challenge study with Imunon’s DNA-based approach for a SARS-CoV-2 vaccine. The NHP pilot study followed the generation of encouraging mouse data and will evaluate the Company’s lead vaccine formulations for safety, immunogenicity and protection against SARS-CoV-2. In completed preclinical studies, Imunon demonstrated a favorable safety profile and efficient immune responses including IgG response, neutralizing antibodies and T-cell responses that parallel the activity of commercial vaccines following intramuscular (IM) administration of novel vaccine compositions expressing a single viral antigen. In addition, vector development has shown promise of neutralizing activity against a range of SARS-CoV-2 variants. Imunon’s DNA-based vaccines have been based on a simple intramuscular injection that does not require viral encapsulation or special equipment for administration.

In April 2022, the Company presented its PLACCINE platform technology at the 2022 World Vaccine Congress in an oral presentation during a Session on Cancer and Immunotherapy. The presentation entitled: “Novel DNA Approaches for Cancer Immunotherapies and Multivalent Infectious Disease Vaccines” highlighted the Company’s technology platform.

PLACCINE has demonstrated the potential to be a powerful platform that provides for rapid design capability for targeting two or more different variants of a single virus in one vaccine. There is a clear public health need for vaccines today that address more than one strain of viruses, like COVID-19, which have fast evolving variant capability to offer the widest possible protection. Murine model data has thus far been encouraging and suggests that the Company’s approach provides not only flexibility, but also the potential for efficacy comparable to benchmark COVID-19 commercial vaccines with durability to protect for more than six months.

In September 2022, the Company provided an update on the progress made in the development of a DNA-based vaccine using its PLACCINE platform technology. The Company reported evidence of IgG, neutralizing antibody, and T-cell responses to its SARS-CoV-2 PLACCINE vaccines in normal mice. In this murine model, the Company’s multivalent PLACCINE vaccine targeted against two different variants showed to be immunogenic as determined by the levels of IgG, neutralizing antibodies, and T-cell responses. Additionally, our multivalent vaccine was equally effective against two different variants of the COVID-19 virus while the commercial mRNA vaccine appeared to have lost some activity against the newer variant.

Final data from its now completed proof-of-concept (“PoC”) mouse challenge study confirmed that a PLACCINE DNA-based vaccine can produce robust levels of IgG, neutralizing antibodies, and T-cell responses. The data demonstrated the ability of the Company’s PLACCINE vaccine to protect a SARS-CoV-2 mouse model in a live viral challenge. In the study, mice were vaccinated with a PLACCINE vaccine expressing the SARS-CoV-2 spike antigen from the D614G variant or the Delta variant, or a combination vaccine expressing both the D614G and Delta spike variants. The vaccination was administered by intramuscular injection on Day 0 and Day 14, followed by challenge with live SARS-CoV-2 virus on Day 42. All three vaccines, including the single and dual antigen vaccines, were found to have a favorable safety profile and elicited IgG responses and inhibited the viral load by 90-95%. The dual antigen vaccine was equally effective against both variants of the SARS CoV-2 virus.

In October 2022, the Company reported partial results from an ongoing non-human primate study designed to examine the immunogenicity of its proprietary PLACCINE vaccine which supported PLACCINE as a viable alternative to mRNA vaccines. The study examined a single plasmid DNA vector containing the SARS-CoV-2 Alpha variant spike antigen formulated with a synthetic DNA delivery system and administered by intramuscular injection. In the study, Cynomolgus monkeys were vaccinated with the PLACCINE vaccine or a commercial mRNA vaccine on Day 1, 28 and 84. Analysis of blood samples for IgG and neutralizing antibodies showed evidence of immunogenicity both in PLACCINE and mRNA vaccinated subjects. Analysis of bronchoalveolar lavage for viral load by quantitative PCR showed viral clearance by >90% of the non-vaccinated controls. Viral clearance from nasal swab followed a similar pattern in a majority of vaccinated animals and a similar clearance profile was observed when viral load was analyzed by the tissue culture infectious dose method.

In March 2023, the Company announced final results from the NHP study involving three vaccine-treated non-human primates. The final data were consistent with the earlier data and showed excellent immunological response and viral clearance. More specifically, in this NHP study, we examined PLACCINE activity against a more advanced SARS-CoV-2 variants and at a DNA dose that was not previously tested in NHP and demonstrated robust IgG responses, neutralizing antibody responses and complete clearance of virus following the challenge as seen in the previous study.

In March 2023, the Company filed with the FDA a pre-IND package in advance of beginning human testing of a SARS-CoV-2 seasonal booster vaccine. In July 2023, the FDA confirmed in a written response our plug and play strategy agreeing that a platform approach to pre-clinical toxicology testing with reference to updated SARS-CoV-2 genes that align with current variant of concern may be used without additional need for toxicology studies. This demonstrated the flexibility and versatility of our platform, which allows for the rapid production and development of any vaccine by simply changing the antigen coding cassette.

On April 18, 2024, the Company announced that it received clearance from the FDA to begin a Phase I clinical trial with a seasonal COVID-19 booster vaccine. The Company filed an Investigational New Drug (IND) application for IMNN-101 in late February. The primary objectives of the Phase I study were to evaluate safety, tolerability, neutralizing antibody response, and the vaccine’s durability (duration of immunogenicity) in healthy adults. Secondary objectives of the study included evaluating the ability of the IMNN-101 vaccine to elicit binding antibodies and cellular responses and their associated durability. The Phase I study enrolled 24 subjects to evaluate three escalating doses of IMNN-101. For this study, IMMN-101 has been designed to protect against the SARS-CoV-2 Omicron XBB1.5 variant, in accordance with the FDA’s Vaccines and Related Biological Products Advisory Committee’s June 2023 announcement of the framework for updated COVID-19 doses.

In February 2025, the Company announced topline safety and immunogenicity data from ongoing analyses of results from the Company’s Phase 1 proof-of-concept clinical trial of IMNN-101. The Phase 1 study was conducted in 24 healthy volunteers as a seasonal COVID-19 vaccine, targeting the SARS-CoV-2 Omicron XBB1.5 spike antigen. IMNN-101 was administered as a single dose vaccine without a booster dose in study participants who were previously vaccinated against the Omicron XBB1.5 variant. Results demonstrated that IMNN-101 is safe and well-tolerated with no serious adverse effects. IMNN-101 induced a persistent 2- to 4-fold increase in serum neutralizing antibody (NAb) titers from baseline through Week 4, further increasing NAb titers between Week 2 and Week 4. The immune response was observed against the XBB1.5 variant and many newer variants following treatment, demonstrating the IMNN-101 vaccine’s cross-reactivity.

On May 15, 2025, the Company announced new data from its first Phase 1 proof-of-concept clinical trial of IMNN-101. Results in 24 healthy volunteers demonstrated IMNN-101’s durability of protection at six months after a single dose targeting the SARS-CoV-2 Omicron XBB1.5 spike antigen variant. IMNN-101 induced up to a 3-fold median increase in the serum neutralizing antibody (NAb) titers from baseline at six months, with initial evidence of a stronger immune response in two higher dose cohorts (2.0 mg and 1.0 mg) compared to a lower dose cohort (0.5 mg). The highest observed increase among the participating volunteers was 8-fold from baseline. IMNN-101 continues to be safe and well tolerated, with no serious adverse effects reported.

In the Phase 1 trial, designed to demonstrate the advantages of Imunon’s technology compared to approved messenger RNA (mRNA) vaccines, IMNN-101 was administered as a single dose vaccine without a booster dose in study participants who were previously vaccinated against the Omicron XBB1.5 variant. Study participants had high baseline immune characteristics, presumably from prior infection and multiple previous vaccinations against COVID-19, and ongoing infection. Modest increases in T-cell responses were observed in trial participants who received multiple immunizations prior to the study. Results from the Phase 1 trial build on data previously announced in February 2025, which showed IMNN-101 induced a persistent 2- to 4-fold increase in serum NAb titers from baseline through Week 4, further increasing NAb titers between Week 2 and Week 4. The immune response was also observed against the XBB1.5 variant and many newer variants following treatment, demonstrating the IMNN-101 vaccine’s cross-reactivity. The Phase 1 clinical data of IMNN-101 is consistent with strong evidence of immunogenicity and protection for the PlaCCine platform in rodents and non-human primates, with prior preclinical results showing comparable protection efficiency (>95%) to a commercial mRNA vaccine in non-human primates.

The Phase I trial was designed to establish proof of concept (PoC) for IMNN-101 as an advancement in vaccine technology. Imunon intends to seek partnership and/or business development opportunities to develop the scientific and business case for IMNN-101 as a future vaccine to address viral mutations. The Company has paused further development of this study at the current time of filing.