rDEN4delta30-4995

rDEN4delta30-4995 is a live attenuated recombinant dengue virus type 4 (DENV4) vaccine candidate. It was developed as a further attenuated derivative of the parent virus rDEN4delta30 by introducing an additional mutation at position 4995 in the NS3 gene, alongside a 30-nucleotide deletion in the 3′ untranslated region (Δ30). This design aimed to reduce replication and potential liver toxicity while maintaining immunogenicity. In phase 1 clinical trials, rDEN4delta30-4995 was shown to be safe, highly attenuated, and immunogenic in healthy adult volunteers. The vaccine did not cause viremia but induced neutralizing antibody responses in most recipients. However, mild adverse events such as asymptomatic localized erythematous rash at the injection site were observed frequently. Due to these local reactions and for further optimization of safety and efficacy profiles, alternative DENV4 vaccine strains were selected for continued development[6][8].