This article illustrates a phase 2/3 control trial conducted in 202 medical centers across 24 countries in patients with non small cell lung cancer cells, previously treated with 1-2 rounds of platinum chemotherapy, expressed a PDL1+ tumor proportion score of at least 1%, and had an EGFR mutation.
1 Patients recruited for the study was made sure not to be have previously been treated with Docetaxel or other type of PD1 inhibitors. 1 The aim of the trial was test the efficacy of Pembrolizumab versus Docetaxel in inhibiting the PD1 pathway in patients with a PDL1+ tumor proportion score of at least 1% or more and previously treated with 1-2 rounds of platinum chemotherapy. 1 Out of 1035 patients with a PDL1+ tumor proportion score of at least 1% or more, 344 were given Pembrolizumab 2mg/kg over half n hour every 3 weeks, 346 given 10mg/kg over half an hour every 3 weeks, and 343 given docetaxel 75 mg/m2 over an hour every 3 weeks.
1 Results illustrated that Pembrolizumab 10mg/kg group followed by the 2mg/kg group showed the highest survival rate between August 2013 and February 2015 compared to docetaxel alone. 1 This similar trend was observed in a smaller amount of patients who had a PDL1+ tumor proportion score of 50% or more 1. Another trend showed a higher death count, 193, from the Docetaxel group post trial completion in contrast to lower death rates in the Pembrolizumab 2mg/kg group with 172, and 156 from the Pembrolizumab 10mg/kg group. 1Overall Pembrolizumab showed consistently higher survival rates in both patients with a PDL1+ tumor proportion score of 1% and 50% or greater in comparison to Docetaxel. 1 Pembrolizumab also incurred less adverse affects compared to Docetaxel and with more patients withdrawing from Docetaxel therapy due to incompatibility or to find alternative treatment.
1 It was suggested from this trial that the PDL1 is a prime targeted pathway for non-small cell lung cancer and that Pembrolizumab 2mg/kg over half an hour every 3 weeks was an agreed upon regimen based on patient outcomes for such patients regardless of age. 1 Based on the articles overall evidences, it has been suggested that Pembrolizumab can be used in patients pretreated platinum chemotherapy in non-small cell lung cancer, a PDL1 positive tumor proportion score of at least 1% or more and either an EGFR mutation of ALK gene rearrange. 1 Although our patient has been newly diagnosed, they have not been previously treated with platinum based chemotherapy and in doing so to make the patient your first concern it would be advisable to tell the patient to try platinum based chemotherapy first with a tyrosine kinase inhibitor prior to initiating Pembrolizumab. 1 Although the patient is reluctant, and the use of Pembrolizumab has shown to increase overall survival over 2 years it can be recommended to provide the patient with a Pembrolizumab starting at the lowest dose 2mg/kg over half hour every 3 weeks. 1