Evaluating the Impact of Subcutaneous Amivantamab Administration

The discussion turned to the subcutaneous (SubQ) formulation of amivantamab, particularly in the context of the MariposaMARIPOSA regimen, where managing toxicities remains a central concern. Enthusiasm around the SubQ version stems largely from the PalomaPALOMA-3 data, which showed it to be noninferior in pharmacokinetics compared towith the IV formulation, with equivalent or slightly improved efficacy outcomes. Importantly, SubQ amivantamab resulted in a significant reduction in injection-related reactions and a lower incidence of thromboembolic events, potentially reducing the need for extended chair time and complex infusion protocols. Additionally, forthcoming data on every-four4-week dosing of SubQ amivantamab is expected to improve patient convenience and clinic capacity.

However, while the SubQ formulation brings clear logistical and safety advantages, it doesn’t appear to mitigate many of the chronic toxicities that significantly impact quality of life. Clinicians noted that issues such as skin rash, nail changes, peripheral edema, and hypoalbuminemia continue to present challenges. These are longer-term effects that remain independent of the drug’s route of administration, meaning the same level of supportive care—including prophylactic anticoagulation and the full COCOON regimen—will still be required. While fewer infusion-related sideadverse effects are certainly a win, these persistent adverse effects limit the SubQ formulation’s impact in being a complete game-changer.

Nonetheless, the shift to a SubQ option may still offer meaningful improvements in patient experience, especially by reducing clinic visits and treatment time. But as the frequency of in-person assessments decreases, there’s concern that toxicity monitoring could become more difficult. Regular follow-up and proactive management will remain essential, particularly given the importance of early intervention in managing skin and systemic toxicities. Overall, the SubQ formulation is viewed as a valuable addition—but not a replacement for close clinical oversight.