A testosterone gel developed by Scottish pharmaceutical firm ProStrakan has won approval in America.
Galashiels-based ProStrakan has teamed up with the US firm Endo Pharmaceuticals to sell Fortesta in the States.
Fortesta is used to treat men with low levels of testosterone, which is linked to osteoporosis and low libido.
The drug is already sold in the UK and Europe and it is estimated that US deal could be worth £60m annually.
The approval by the US food and drug administration has already triggered a payment of around £8m to ProStrakan from Endo.
Further "milestone" payments could take the total much higher if sales targets are achieved in America.
Meanwhile, ProStrakan said that it was still evaluating a number of offers for the company.
Last month the Borders firm rejected a bid from the Dutch group Norgine.