Gilead had routine access to the foundation's data and used that information to decide how much to give, the feds allege. Gilead further knew the price it had set for Letairis could pose a barrier to patients filling prescriptions, the DOJ says. RELATED: Teva funneled kickbacks through copay assistance charities for MS med Copaxone: DOJ Plus, Gilead specifically referred Medicare patients to the foundation for assistance, the DOJ says. Under federal law, pharma companies cannot, either "directly or indirectly," make payments to induce Medicare patients to purchase their medicines. That includes payments for copays.