Intravenous versus subcutaneous administration of pembrolizumab. 

The discussion between these two experts on different tumour types focused on a poster comparing intravenous (IV) and subcutaneous (SC) administration of pembrolizumab across three tumour types: non-small cell lung cancer, melanoma, and renal cell carcinoma. The study included two parallel groups—one receiving pembrolizumab intravenously and the other subcutaneously—with patients later crossing over so each experienced both administration methods. The primary goal was not to compare efficacy, which previous studies have already shown to be equivalent, but rather to evaluate patient and physician preferences regarding treatment mode. Pembrolizumab SC administration has already received regulatory approval in the United States, providing a precedent for broader clinical implementation.

Results indicated that approximately two-thirds of patients preferred the subcutaneous route, while about one-third favoured IV administration. The predominant reason cited for preferring SC treatment was reduced time spent in the hospital and greater overall convenience. The shorter administration time allowed patients to complete their treatment visits more efficiently, which was particularly valued by those undergoing long-term therapy. Physicians expressed similar preferences, also favouring subcutaneous dosing because it optimises the workflow in oncology day clinics by reducing infusion chair occupancy and allowing more patients to be treated within the same timeframe.

From the clinician’s perspective, SC pembrolizumab represents a potentially meaningful logistical improvement. However, pulmonologists, who are less accustomed to administering SC biologics, expressed some uncertainty about integrating this approach into their daily practice. Medical oncologists, who have prior experience with other SC monoclonal antibodies such as trastuzumab in breast cancer, reported reassuring parallels. In those earlier cases, SC trastuzumab demonstrated equivalent efficacy and safety compared to IV infusion, and subsequent preference studies showed that patients and physicians overwhelmingly favoured the subcutaneous route. A similar pattern is now emerging for pembrolizumab.

A further dimension of discussion concerned the experience of nurses in oncology day clinics. Although not formally assessed in the poster, previous experience with SC trastuzumab suggests that nurses generally view this approach positively. They benefit from shorter administration times and closer one-to-one patient interaction during the few minutes required for injection. This interaction can strengthen communication and contribute to better patient satisfaction and treatment adherence. Importantly, SC injections take only a few minutes, freeing up infusion resources and simplifying scheduling logistics in busy oncology centers.

Regarding administration settings, the speakers noted that while SC pembrolizumab is currently given in hospital day clinics, it may eventually be delivered in home-care settings under appropriate supervision. This would require formal agreements between oncology centers and home nursing services, ensuring safety monitoring and communication between caregivers and treating physicians. Such a shift could further enhance convenience for patients and reduce hospital workload, provided that strict clinical protocols are maintained.

In summary, the study and subsequent discussion highlighted that both patients and physicians favour SC pembrolizumab due to its comparable efficacy, shorter treatment time, and logistical advantages. Experience from analogous therapies supports the feasibility and safety of this approach, suggesting that SC immune checkpoint inhibitors may soon become a routine part of clinical practice. The broader implementation will depend on healthcare infrastructure, nurse training, and regulatory adaptations; however, early feedback suggests that the transition could improve patient experience and streamline oncology care delivery.