Note: If you're new to Spider-Man, Toxin is a symbiotic spawn of Carnage, as described in the recent Venom/Carnage limited series. Carnage himself was originally the spawn of the symbiote Venom.
Back in the excesses of the 90's symbiotes became seen as a guaranteed way to get slavering fanboys to buy any sort of crap comic, eventually leading to the massive symbiote overload that was Venom: Separation Anxiety. At that point, it finally became clear that symbiotes had been massively over-exposed, to the point of fan backlash.
While Ock's recent rash of limited series appearances Spider-Man: Doctor Octopus - Negative Exposure, Spider-Man: Doctor Octopus - Out of Reach, and Spider-Man: Doctor Octopus - Year One) are all timed to capitalise on Ock's recent movie appearance, he's still as fresh as a daisy in comparison to anything starting with "symb".