Merck (NYSE: MRK), known as MSD outside the United States and Canada, today announced that the European Commission (EC) has approved an expanded label for KEYTRUDA, Merck’s anti-PD-1 therapy, as monotherapy for the treatment of adult and pediatric patients aged 3 years and older with relapsed or refractory classical Hodgkin lymphoma (cHL)...This approval is the first pediatric approval for KEYTRUDA in the European Union (EU).