Pfizer and GlaxoSmithKline are increasing sales of cut-price pneumonia vaccine to developing countries by more than 50 percent, marking the scale-up of an international program to protect millions of children. The Global Alliance for Vaccines and Immunisation (GAVI) is buying an additional 180 million doses of Pfizer's pneumococcal vaccine Prevenar 13 and a similar quantity of GSK's Synflorix at a deeply discounted price of $3.50 a shot. The two companies said on Friday they would supply the extra vaccine through 2023, building on an original commitment last year to supply 300 million doses apiece...A Pfizer spokeswoman said $3.50 was more than a 90 percent reduction from prices charged in some industrialized countries. The pneumococcal vaccination program was initially started a year ago in Nicaragua and has now been rolled out to 15 other countries in Africa and Latin America.