SK Chemicals Co., a petrochemical unit of South Korea's third-largest conglomerate SK Group, said Wednesday that it has signed a deal with global vaccine maker Sanofi Pasteur Inc. to jointly develop and sell a next-generation vaccine. SK Chemicals will develop the vaccine for pneumococcal with Sanofi Pasteur and produce it at its plant in Andong, 268 kilometers southeast of Seoul, the company said in a regulatory filing. Pneumococcal is a bacterial infection responsible for up to 1.6 million deaths a year worldwide, according to the World Heath Organization.