Journal: Therapeutic delivery
This review article evaluates subcutaneous (SC) atezolizumab (co-formulated with rHuPH20) as an alternative to the intravenous (IV) formulation in NSCLC, focusing on pharmacokinetics, efficacy, safety, patient experience, and operational impact.
Key points:
- Pharmacokinetics:
- A fixed 1,875 mg SC dose every 3 weeks achieves bioavailability and steady-state exposure non-inferior to IV.
- Prespecified pharmacokinetic non-inferiority margins are met, with maintained PD-L1 target engagement.
- Efficacy:
- Across phase I–III trials in previously treated NSCLC, objective response rate, PFS, and OS are comparable between SC and IV administration.
- No loss of antitumor activity is seen with the SC route based on available data.
- Safety:
- Overall safety profile mirrors IV atezolizumab, including the type, frequency, and severity of immune-related adverse events.
- The main route-specific toxicity is infrequent, generally mild injection-site reactions.
- No new safety signals attributable to SC delivery are identified.
- Patient-reported outcomes and preference:
- Patients consistently prefer SC administration, citing shorter visit times, lower treatment burden, and greater convenience.
- SC dosing involves an approximately 7-minute injection, contributing to reduced chair time.
- Operational and system-level impact:
- Time-and-motion analyses suggest meaningful clinic capacity gains, especially in maintenance settings and resource-limited environments.
- Implementation considerations include:
- Usual immunotherapy toxicity monitoring.
- Nursing training for large-volume SC injections.
- Rigorous verification of route of administration.
- Unresolved questions and future directions:
- Real-world effectiveness and large-scale pharmacovigilance remain to be fully characterized.
- Determinants of inter-individual variability in SC bioavailability are unclear.
- Optimal injection technique and site require further study.
- Data are limited regarding use with perioperative regimens and chemotherapy combinations.
Overall, the evidence summarized supports SC atezolizumab as a clinically robust, operationally efficient, and patient-preferred alternative to IV administration in NSCLC, with comparable pharmacokinetics, efficacy, and safety, and distinct workflow advantages.