They don't get better prices because they are operating in a system where access to key drugs is a key differentiator. Penny pinching on access drugs (as does NICE in the UK on behalf of the NHS) wouldn't be a good look for an insurance company as they pitch for your business. The only way negotiations with Pharma companies will work is is you actually refuse to pay over-inflated prices, again as-does NICE. And the only way this can be justified is to have a centrally mandated $ per unit 'utility' (aka QALY) beyond which you won't pay.
Private insurers aren't motivated to do any of this because high drug prices don't hurt their bottom line.
Private insurers aren't motivated to do any of this because high drug prices don't hurt their bottom line.