Yes, Roundup is more dangerous compared to glyphosate alone. In May 2018, the U.S. National Toxicology Program (NTP) released a report on the evaluations conducted on glyphosate formulations.
According to the chief of the NTP Laboratory, the formulations of glyphosate are more toxic and were cytotoxic. This served as important information as it is always the formulated products such as Roundup that people are exposed to.
Various studies have established that ingredients present in Roundup increase the toxicity of glyphosate by making it easy for the chemical to penetrate plant and animal cells.