A quick search on "sci fi novel, egg room, monkeys" found Seize the Night by Dean Koontz. The Kirkus review describes it thus:
This tour de force, though less intense than Intensity (1996), has Koontz, the nimble master of the macabre, inventing a hugely empty California army base once used for secret experiments and now, in its vast, moonlit state, called Dead Town. Poetry freak Christopher Snow, also the hero of Fear Nothing, suffers from a rare genetic disorder, xeroderma pigmentosum: his skin can’t bear light of any sort. Thus he dresses only in black, wears dark shades, inhabits a house lit by bulbs in red lantern glass, sleeps by day, goes out only after sunset, and so on. Chris lives next to Wyvern Army Base, in Moonlight Bay, whose leading citizens know that terrible experiments at Wyvern produced genetically enhanced, intelligent monkeys, birds, snakes, coyotes, and humans, all richly menacing and still infesting the base. Many of the experimental humans were afflicted by a rogue retrovirus causing them to fall into beastly rages signaled by nocturnal eyeshine. That said, Koontz takes on a triple, or perhaps quadruple, oh, hell, quintuple plot, featuring serial murderers; an incredible Egg Room located three floors underground where, apparently, the experimental subjects were enhanced; and an invasion of the present by swift alien worms coming from sidetime and likely to take over the planet. Will murder-minded experimental folk now waltz around every continent? They’re an unpleasant bunch. When an old girlfriend’s boy is kidnaped and whisked off to the base, Chris follows with his enhanced dog Orson (as in Welles), a genius on a par with intelligent humans. Chris’s moonlit adventures in Dead Town, aided by his wisecracking crew of far-out buddies, form a story that bends into the bizarro mirror-world of Neverland. Heavy suspense, no sex, and darker than Nancy Drew. With headlong glee, Koontz again unveils encyclopedic intelligence about how things work in the physical world—and how to bolt sentences into the moonlight.