Meningococcal group B vaccine(Pfizer Inc.)

SHANGHAI and PERTH, Australia, March 30, 2026 /PRNewswire/ -- Delonix Bioworks, a clinical-stage biotechnology company pioneering genetically engineered bacterial vaccines, today announced the initiation of first-in-human (FIH) dosing in a Phase 1 clinical trial of DX-104. DX-104 is an innovative Group B meningococcal (MenB) vaccine candidate developed using the company's proprietary OMV Plus™ platform. The Phase 1 trial is a randomized, double-blinded, positive-controlled study evaluating the safety and immunogenicity of DX-104 in healthy adult participants. The trial is currently underway in Perth, Australia. Following successful completion of the preliminary safety assessment by initial sentinel participants, the study has proceeded to broader enrollment as planned. "The initiation of this Phase 1 trial is a transformative milestone for Delonix," said Dr. Qiubin Lin, Founder and CEO of Delonix Bioworks. "Beyond advancing our MenB program, this study serves as a critical clinical validation of our OMV Plus™ platform. We are rapidly advancing our OMV-based pipeline—targeting Pertussis, N. gonorrhoeae, and K. pneumoniae—to deliver breakthrough solutions against the global threat of antimicrobial resistance (AMR)." About MenB (Meningococcal Group B) Invasive meningococcal disease (IMD) remains a devastating, rapid-onset bacterial infection that primarily threatens infants, adolescents, and young adults. Globally, Serogroup B has become the dominant driver of IMD, now responsible for approximately 50% of cases with a steadily rising prevalence. While established vaccines such as GSK's Bexsero® and Pfizer's Trumenba® have validated the significant clinical and commercial demand—with Bexsero reporting approximately $1.58 billion in sales in 2025—critical gaps remain regarding global strain coverage, manufacturing complexity, and equitable access. About DX-104 DX-104 is an investigational Group B meningococcal (MenB) vaccine candidate. Built on the OMV Plus™ platform, it utilizes genetically engineered outer membrane vesicles (OMVs) to ensure precise antigen presentation. The candidate aims to address the significant global unmet need for more consistent and broadly protective vaccines against serogroup B meningococcal disease. About Delonix Bioworks Delonix Bioworks is a clinical-stage biotechnology company at the forefront of developing next-generation genetically engineered bacterial vaccines. Leveraging its proprietary OMV Plus™ platform, the company produces high-yield, cost-effective, and precisely engineered outer membrane vesicles (OMVs) designed for superior antigen presentation and immunogenicity. Delonix is dedicated to advancing a robust pipeline of first-in-class and best-in-class programs addressing critical unmet needs, including vaccines for Meningococcal B, pertussis, gonorrhoeae, and K. pneumoniae. For more information, please visit or contact [email protected]. SOURCE Delonix Bioworks 21% more press release views with Request a Demo

Delonix Bioworks, a clinical-stage biotechnology company based in Shanghai and Perth, has initiated first-in-human dosing of the DX-104 vaccine, a MenB OMV vaccine candidate built on the company’s proprietary OMV Plus platform. As per a clinicaltrials.gov listing, the Phase I clinical trial is a randomized, double-blinded, positive-controlled study evaluating safety and immunogenicity in healthy adults in Perth, Australia. The enrollment target is 30 with participants to receive DX-104 or Bexsero at months 0, 1, and 6, with primary completion expected in May 2027. DX-104 uses genetically engineered outer membrane vesicles to present bacterial antigens, targeting serogroup B Neisseria meningitidis. The specific molecular antigens displayed on the OMVs have not been disclosed. The first-in-human DX-104 trial also serves as a platform validation event for the OMV Plus technology, which Delonix intends to apply across a broader pipeline including vaccines for pertussis, N. gonorrhoeae, and K. pneumoniae. Research context The scientific rationale for an OMV-based meningococcal B vaccine rests on decades of clinical and immunological evidence. Outer membrane vesicles derived from N. meningitidis contain native surface proteins in their natural conformation, stimulating bactericidal antibodies—the accepted correlate of protection against invasive meningococcal disease. Earlier OMV vaccines developed for outbreak control in Norway, Cuba, and New Zealand demonstrated strain-specific efficacy but limited breadth. Advances in genetic engineering now allow modification of OMVs to display optimized or additional antigens and reduce reactogenicity. This trajectory underpins the OMV Plus platform, though peer-reviewed data specific to DX-104’s engineered antigen composition are not yet available. The current standard of care for MenB prevention centers on two licensed vaccines: GSK’s Bexsero, a four-component vaccine combining recombinant proteins (fHbp, NadA, NHBA) with an OMV component, and Pfizer’s Trumenba, a bivalent recombinant fHbp vaccine. Both have been in use since the mid-2010s. More recently, the field has consolidated around pentavalent combination products: Pfizer’s Penbraya (approved October 2023) and GSK’s Penmenvy (approved February 2025) each combine MenB and MenACWY components into a single vaccination series for individuals aged 10–25. Despite commercial validation—Bexsero reported approximately USD 1.58 billion in 2025 sales—gaps persist. Strain coverage estimates for existing vaccines vary by region, ranging from roughly 60% to 91%. Manufacturing complexity contributes to per-dose costs that limit access in low- and middle-income countries, where meningococcal disease burden is concentrated. Adolescent MenB vaccination rates in the United States remain around 30%-35%, well below MenACWY uptake. The WHO’s “Defeating Meningitis by 2030” roadmap has called for broader access to affordable MenB vaccines. Competitive landscape DX-104 enters a field where no novel MenB vaccine candidates beyond the established GSK and Pfizer franchises appear to be in late-stage clinical development. Bexsero and Trumenba remain the only MenB-specific vaccines with active clinical programs, primarily consisting of post-marketing and life-cycle management studies. An earlier nine-valent OMV vaccine (NonaMen, Norwegian Institute of Public Health) targeting multiple PorA subtypes completed early trials but is not currently recruiting. Regional outbreak-response OMV vaccines such as MeNZB and VA-MENGOC-BC are no longer in active development. The absence of clinical-stage competitors pursuing new OMV-based or recombinant MenB approaches means DX-104 occupies a relatively uncrowded space for a next-generation candidate, though it faces a long development timeline against entrenched products with extensive real-world evidence. The differentiation Delonix claims—broader strain coverage, simplified manufacturing, and lower cost—will require clinical data to substantiate. The company has not disclosed which antigens are engineered into its OMVs, making it difficult to assess immunological differentiation from Bexsero’s existing OMV component. Your email address will not be published. Required fields are marked * Comment * Name * Email * Website