Loading
The third PD-1 antibody tested in this rare and fast-growing skin cancer shrank it in more than half of the people who took it, and most of those responses lasted years. Six in ten were still alive three years later, in a disease that used to kill within months.
Merkel cell carcinoma is rare, aggressive and unusually visible to the immune system, either because it carries the Merkel cell polyomavirus or because it is driven by ultraviolet damage with a very high mutational burden. POD1UM-201 tested retifanlimab, a humanised PD-1 antibody, in 101 chemotherapy-naive patients with recurrent locally advanced or metastatic disease across 34 sites in the United States, Canada and Europe.
The objective response rate was 54.5 per cent (95 per cent confidence interval 44.2 to 64.4), made up of 18 complete responses (17.8 per cent) and 37 partial responses (36.6 per cent), with a disease control rate of 60.4 per cent. Duration matters more than rate in this disease, because chemotherapy responses had been measured in months: median duration of response was not reached in those with a complete response, with a lower confidence bound of 14.0 months, and was 25.3 months in those with a partial response. Median progression-free survival was 16.0 months (9.0 to 32.2) and median overall survival was not reached, with 63 per cent of patients alive at three years.
Grade 3 immune-related adverse events occurred in 11 patients (10.9 per cent), in keeping with the class.
Retifanlimab became the third PD-1 or PD-L1 antibody approved for this disease after avelumab and pembrolizumab, and the three have never been compared with each other. What matters is not which is chosen but that roughly half of the patients respond and most responders keep responding, which is the single largest change in the history of this cancer.
Numbers are from the trial as recorded here; see the source links in the table below. This is orientation, not medical advice: ask your team how closely the trial population matches you.
101 treated.
95 per cent confidence interval 44.2 to 64.4; 18 complete and 37 partial responses
Sourcemedian overall survival not reached
Source11 of 101 patients
Source| Endpoint | Arm | n | Value | HR (95% CI) | p | Source |
|---|---|---|---|---|---|---|
| Objective response rateprimary | Retifanlimab 500 mg every 4 weeks | 101 | 54.5% | - | - | link |
| Median progression-free survival | Retifanlimab 500 mg every 4 weeks | 101 | 16 months | - | - | link |
| Overall survival at 3 years | Retifanlimab 500 mg every 4 weeks | 101 | 63% | - | - | link |
| Grade 3 immune-related adverse events | Retifanlimab 500 mg every 4 weeks | 101 | 10.9% | - | - | link |
Shares Retifanlimab, Incyte, Immune checkpoint inhibitors.
Shares Retifanlimab, Incyte, Immune checkpoint inhibitors.
Shares STAMP (EA6174), Merkel cell carcinoma, Skin cancer (all types).
Shares Retifanlimab, Incyte, Immune checkpoint inhibitors.
Shares Immune-related adverse events (irAEs), Tumour mutational burden (TMB), Skin cancer (all types), PD-1.
Shares Immune-related adverse events (irAEs), Tumour mutational burden (TMB), PD-1, Immune checkpoint inhibitors.
Shares Immune-related adverse events (irAEs), Skin cancer (all types), PD-1, Immune checkpoint inhibitors.
Shares Immune-related adverse events (irAEs), Tumour mutational burden (TMB), Skin cancer (all types), PD-1.