Study data published in the journal The Lancet revealed that Merck & Co.'s immunotherapy Keytruda has efficacy in the treatment of patients with advanced non-small-cell lung cancer (NSCLC) that expressed the PD-L 1 protein. In the Phase II/III KEYNOTE-010 trial, data from which were also presented at the European Society for Medical Oncology Asia annual meeting, Keytruda was found to prolong overall survival (OS) in patients with PD-L1-expressing NSCLC versus chemotherapy. Merck Research Laboratories president Roger Perlmutter said "in this study in patients with PD-L1 expression of one percent or greater, Keytruda demonstrably improved [OS] compared to chemotherapy in previously-treated patients with non-small cell lung cancer, including both squamous and non-squamous histologies."
In the study, 1034 patients with advanced PD-L1-positive NSCLC were randomised to treatment with Keytruda, at doses of 2 mg/kg or 10 mg/kg, once every three weeks.or docetaxel The primary endpoints of the study were OS and progression-free survival (PFS) in both the whole population and in patients in whom at least 50 percent of their tumour cells expressed PD-L1. Tumour response was assessed first at nine weeks and then every nine weeks thereafter.
Results from the study showed that in the total population, the median OS was 10.4 months in the low-dose Keytruda arm and 12.7 months in the high-dose Keytruda arm, compared to 8.5 months for docetaxel-treated patients. In addition, the estimated one-year OS rates for the low-dose and high-dose Keytruda groups were 43.2 percent and 52.3 percent, respectively, versus 34.6 percent for the docetaxel arm. Conversely, no significant difference in PFS was observed among the three study groups.
Meanwhile, among patients with PD-L1 expression in at least 50 percent of their tumour cells, the median OS times for the low-dose and high-dose Keytruda groups were 14.9 months and 17.3 months, respectively, compared to 8.2 months for docetaxel. Moreover, among these patients, the median PFS were 5.0 months for the low-dose Keytruda group and 5.1 months for the high-dose Keytruda group, versus 4.1 months for the docetaxel group.
Study author Roy Herbst remarked "this is an exciting time, and studies such as KEYNOTE-010 with Keytruda are paving the way to a better understanding of how to identify the right medicine for each patient," continuing "now that we have learned which patients are most likely to benefit from the anti-PD-L1 strategy, we could begin moving this drug to the earlier setting stages."
Merck indicated that it plans to submit a supplemental biologics license application to the FDA based on the findings of this study by the end of the year, while a regulatory submission to the European Medicines Agency is anticipated for next year. Keytruda was initially granted accelerated approval by the FDA for the treatment of patients with previously treated advanced or unresectable melanoma in September 2014, with its indication expanded in October this year to include PD-L1-positive NSCLC. The drug was also approved in the US on December 18 for advanced or unresectable melanoma as a first line therapy. Keytruda has also been cleared in Europe for the treatment of both treatment-naïve and treatment-experienced patients with advanced melanoma.
