The short version
14 companies supply this market — deep enough that no single failure threatens the supply. The generic price has fallen 35% in a year, to $0.1400 per unit — and generics that get this cheap tend to get abandoned rather than defended. The brand (Cialis) runs $53.69 per unit — 361× more. Put together: this looks like a healthy supply — the boring kind, which is exactly what you want.
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