What's lyumjev's duration of action?

Lyumjev (bamlanivimab + etesevimab) – Duration of Action

Because Lyumjev delivers both antibodies in a single intramuscular injection, the overall neutralizing effect is expected to last roughly 4 weeks (about 28 days) from the time of administration. The drug’s pharmacokinetic data in the FDA prescribing information show that serum concentrations decline slowly over this period, with a terminal half‑life of ~28 days for bamlanivimab and ~21 days for etesevimab.

Reference: U.S. Food & Drug Administration (FDA) prescribing information for LYUMJEV® (bamlanivimab + etesevimab) – “The half‑life of bamlanivimab is approximately 28 days and of etesevimab is about 21 days; a single dose is expected to maintain neutralizing activity for up to 4 weeks.”