Food of the Gods II (1989)

Neil Hamilton, a professor at Hamelin University, is called in to help one of his old mentors, Dr. Kate Travis. She has been giving experimental growth hormones to Bobby, a boy with a growth deficiency. Unfortunately it worked too well. Bobby has grown gigantic - and violent. Neil realizes something unique in the boy's blood chemistry has affected Travis' hormones. His efforts to synthesize an antidote only creates a more perfected growth formula. When student activists raid Neil's lab, they accidentally release some lab rats Neil had given the formula to. These rats, now giant, feast on the activists and begin terrorizing the college. A very loose sequel to the 1976 film.