Invivyd, a small biotech company, is developing VYD2311, an injectable, low-dose monoclonal antibody designed to protect against Covid-19 infection in a vaccine-like manner. On Tuesday, the company reported results from its Phase 3 LIBERTY study, which compared VYD2311 against Pfizer's established mRNA vaccine, Comirnaty.
The study showed that after six days, 57% of participants who received VYD2311 reported headaches, chills, fatigue, or injection-site pain — the typical side effects associated with vaccinations. In the Comirnaty arm, 91% reported the same side effects, a statistically significant difference. VYD2311 was also better tolerated at 56 days, and the study found it could be combined safely with Comirnaty.
The source, STAT's Adam Feuerstein, notes that an FDA hurdle may await Invivyd, though the available text does not specify what that hurdle is. The company's approach aims to offer an alternative for people who perceive limitations in vaccines, positioning the antibody as a potential prophylactic option distinct from mRNA immunization.