That doesn't logically follow. Why would a one time treatment win the market? Lasik is a one time treatment that certainly hasn't eliminated the market for daily contacts. The ability to buy a house hasn't eliminated the market for renting. The one time treatment has to pay for its development in a single dose, the recurring treatment can amortize its costs over many doses. In general, you will have to pay a premium for the convenience of a single dose, and many people can't justify that cost.