J&J Abandons Phase 2 Dengue Candidate as Part of Continued Vaccination Withdrawal

Johnson & Johnson’s infectious disease unit has lost yet another prospective product in mosnodenvir, a dengue virus vaccine.

Mosnodenvir targets two dengue virus proteins that are believed to come into close proximity and possibly interact. The vaccine had been spared from a series of decisions made last year to consolidate infectious diseases and vaccines into a single business unit at J&J. This restructuring resulted in the discontinuation of some focused programs, including a late-stage respiratory syncytial virus initiative and the sale of an E. coli vaccine to Sanofi.

However, Mosnodenvir has faced challenges in the clinic. J&J halted one trial due to the impact of COVID-19 on enrollment and suspended recruitment for another in 2022. Despite these setbacks, loyalty to the mosnodenvir project appeared to pay off when, in October 2023, the vaccine demonstrated a dose-dependent antiviral response in phase 2 trials for dengue virus serotype 3.

Yet even this promising data was not enough to secure the future of mosnodenvir. This morning, J&J announced that it would be halting a second phase 2 field study, citing a “strategic rebalancing of the company’s communicable diseases R&D portfolio.” J&J emphasized that the decision was unrelated to any safety concerns regarding the vaccine.

Looking ahead, J&J stated that it will continue to support the fight against dengue by sharing study results with the medical community. Dengue has been a focus for J&J over the past 15 years, and in 2022, the company launched the Satellite Center for Global Health Discovery at Duke-NUS Medical School. The center is dedicated to advancing early-stage research to combat the rising threat of flaviviruses, including dengue and Zika.