By Patrick Wingrove

Oct 16 (Reuters) - Roche ROG.S on Thursday launched direct-to-consumer U.S. sales of its influenza antiviral pill Xofluza at a discounted cash price of $50, following similar moves by rivals as they scramble to address pressure from the Trump administration to lower prescription drug prices paid by Americans.

The Xofluza cash price, offered by Roche's U.S. biotech unit Genentech at 70% below list price, will be available to insured and uninsured patients through same-day delivery from Alto Pharmacy, Amazon Pharmacy, and Mark Cuban Cost Plus Drug Company. Major U.S. pharmacy chains like CVS CVS.N will not be involved, Roche confirmed.

The administration of U.S. President Donald Trump has said it plans to launch, likely early next year, a website called TrumpRx that aims to help consumers buy some medicines directly from the manufacturers. Roche said its new program will not be accessible through TrumpRx, but that it will continue to evaluate its options.

Few people in the U.S. pay cash for prescription medications. Most have insurance - either commercial or federal plans like Medicare - that charge them a fixed co-pay or percentage of a drug cost. Insurers typically receive confidential discounts or rebates directly from drug manufacturers, bringing their costs well below list prices.

The Swiss drugmaker already offers a coupon for Xofluza that brings the out-of-pocket cost down to $35 for some insured and uninsured patients.

Xofluza is used to treat flu in patients aged 12 years and older who have had symptoms for no more than two days.

Trump, in an effort to lower drug costs for U.S. patients who pay far more than in other wealthy nations, has so far struck deals with Pfizer PFE.N and AstraZeneca AZN.L to lower their prescription drug prices in the Medicaid program for lower-income Americans in exchange for tariff relief.

Roche said its new program supports that goal and is similar to one from rival Amgen AMGN.O, which launched discounts for cash-paying patients this year.

Analysts expect Xofluza to generate $340 million in sales this year.

Roche, via Genentech, was one of 17 major drug companies to receive a letter from Trump in July demanding they charge U.S. patients the same price as people pay in other high-income countries, create direct-to-consumer channels and increase investment in the U.S. Trump threatened to impose 100% tariffs on branded drugs to those companies that failed to comply.

(Reporting by Patrick WingroveEditing by Bill Berkrot)

((Patrick.Wingrove@thomsonreuters.com;))