Anti-PD1 after ipi.....

Anti-programmed-death-receptor-1 treatment with pembrolizumab in ipilimumab-refractory advanced melanoma: a randomized dose-comparison cohort of a phase 1 trial

Robert, Ribas, Wolchok, Hodi, Hamid, Kefford, Weber, et al.  The Lancet. July 15, 2014

Pembro at 2mg/kg and 10mg/kg every three weeks were compared in 173 patients who had progressed after at least two ipi doses.  They were randomly assigned to the dose sets. Median follow-up was 8 months.  Overall response rate was 26% at both doses.  Treatment was fairly well tolerated  with similar safety profiles in both dosage groups.  Most common side effects were fatigue, rashes, and itching.  "Results suggest that pembrolizumab...might be an effective treatment in patients for whom there are few effective treatment options."

These results are consistent with what we are learning from other studies.  Ipi naive patients have a better response rate to anti-PD1, but some folks can still attain positive responses to anti-PD1 even when they have progressed on ipi.

Infomation presented at ASCO included these overall response data:

Pembro every three weeks in ipi naive patients = 40% overall response rate
Pembro every three weeks in ipi refractory patients = 28% overall response
Nivo in ipi naive patients = 41% overall response rate.

For more details you can check the post below:
Earlier post with info from ASCO comparing - nivoipi-combo-nivo-vs-pembro-pd-l1

Best - c