Perl supports something called bit vectors. Essentially, it's just a way to treat a string of bits as an arbitrary length byte.

You'd use something like $bv = pack('B*', $byte); to turn your string into a bit vector. You can use vec to access individual elements.

If you were to do that, it might simplify your code somewhat. The first regex could be replaced with:

if ((vec($bv, 0, 1) == 1) and (vec($bv, 4, 1) == 0)) {
    # do something 
}
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That's untested, as I've not found a good use for this yet.

I'd probably turn your string into an integer and use bitwise operations to work on it.

Update: After studying this a bit more, it'll take more work to use vec to replace the regex. Use logical and, not, or, and xor as tye suggests. The bit-shifting operands will also come in handy.