Gnaw: Food of the Gods II (1989)
A unique growth hormone goes awry when animal rights protestors accidentally free infected lab rats, which causes an epidemic of man eating vermin.
Paul Coufos (CHOPPING MALL), Lisa Schrage (HELLO MARY LOU: PROM NIGHT II), Colin Fox (LEFT BEHIND: THE MOVIE) and Jackie Burroughs (OVERDRAWN AT THE MEMORY BANK) star in director Damian Lee's loose sequel to the 1976 film loosely based on the novel "The Food of the Gods and How It Came to Earth" by H.G. Wells. Damian would later direct ABRAXIS, GUARDIAN OF THE UNIVERSE.
Recommended by Super Eyepatch Wolf, an anime Youtuber, in his 2019 Best of Fall/Halloween video (though this clearly isn't a 2019 product).
Brief glimpses of the clips he used and the trailer? https://www.youtube.com/watch?v=BYZJPWKNuO8
This and it's predecessor, Food of the Gods... both need a proper riffing treatment.