The journey from deciding to start pembrolizumab to receiving your first injection involves several steps - each of which exists for good clinical reasons. Understanding the process helps set expectations and removes uncertainty about what is happening and why.
Oncologist review and prescription
Pembrolizumab is a prescription-only medicine. Before any dose can be administered, a qualified oncologist must review your clinical information, confirm eligibility, and issue a formal prescription. This includes reviewing your cancer type, PD-L1 result or other qualifying biomarker, treatment history, performance status, relevant co-morbidities, and current medications.
The prescription specifies the dose and schedule. The two approved subcutaneous schedules for most indications are 200mg every three weeks and 400mg every six weeks. The oncologist selects the schedule based on your indication and clinical circumstances.
Drug sourcing and dispensing
Pembrolizumab is dispensed by a specialist pharmacy following receipt of the prescription. The drug is manufactured as a ready-to-use syringe device for subcutaneous administration. It is temperature-sensitive and must be stored at 2-8 degrees Celsius throughout the supply chain - a requirement managed by specialist oncology pharmacies with appropriate cold-chain logistics.
For home administration, the drug is transported to your address in a validated cold-chain container and is typically delivered on or shortly before the day of treatment, to minimise the time it spends outside controlled storage.
Before each cycle
The prescribing process repeats - in abbreviated form - before each treatment cycle. The oncologist reviews your most recent blood test results and any clinical concerns raised since the previous dose. If results are satisfactory and no new concerns have emerged, treatment is authorised to proceed. If there are concerns - an elevated liver enzyme, a new symptom requiring investigation - treatment may be deferred until the issue is clarified.
This cycle-by-cycle review is not bureaucratic overhead; it is a core part of the safety framework around pembrolizumab treatment.
Want to understand the full process before deciding?
Start with the eligibility check. An oncologist reviews it within 24 hours, and the Welcome Call covers the full journey from start to first injection.
Check your eligibility