SC Q4W in Practice — Workflow, Dose Modifications, and Patient Conversations

Dr. Nagasaka and Dr. Goldberg discuss how the subcutaneous Q4W regimen reshapes infusion-center workflow and patient conversations. Dr. Goldberg notes that a 5-minute injection is substantially easier to schedule than a multi-hour infusion, that infusion-chair availability is a real constraint at most centers, and that halving annual visits is meaningful for nearly every patient. Dr. Nagasaka adds that the subcutaneous formulation also makes treatment initiation easier, since the day 1 and day 2 split-dose start required with intravenous administration is no longer needed. Both discuss how to approach less-frequent dosing for patients already doing well on intravenous or subcutaneous Q2W amivantamab. Dr. Goldberg observes that some patients are reluctant to change a regimen they are tolerating, but that the PALOMA-3 pharmacokinetic data — showing similar drug exposure between the intravenous and subcutaneous formulations and at least comparable efficacy with the subcutaneous form — generally reassures patients. She notes that the higher dose used with Q4W administration can be a consideration for tolerability-fragile patients, and that some may prefer to remain on a Q2W schedule.

On dose modifications, Dr. Goldberg emphasizes that the MARIPOSA finding of preserved progression-free survival in patients who required dose reductions has changed her counseling. She raises the possibility of dose modification at treatment initiation, frames reductions as a way to remain on therapy longer, and reassures patients that lowering the dose does not appear to compromise outcomes. Dr. Nagasaka agrees that supportive care should be tried first, with dose reduction reserved for when it is needed.

In the next episode, "Safety, Tolerability, and the AE Profile of SC Q4W in Cohort 5," Dr. Goldberg reviews the AE profile and proactive management strategies.