What they did
356 people with persistent facial redness from rosacea were randomly assigned to oxymetazoline cream at 0.5%, 1%, or 1.5%, either once or twice daily, or to a cream with no drug in it, for 28 days. The point of the study was to pick a strength and a schedule, not to establish that the drug works. Each active arm was compared with its matching placebo.
What they found
Every active strength beat its matching placebo. The 1% strength was clearly better than 0.5% and no worse than 1.5%. Once a day was enough. That is how the 1% once-daily product came to be.
What this does not show
This is a dose-finding study, so 356 people are divided across several arms and each group is small. "No worse than 1.5%" means no difference was found between those two strengths, not that they are proven equal. It ran 28 days, which says nothing about months or years of use, or about stopping. No figures for how much redness fell are given here, only which arms came out ahead.
Who paid for it
The paper does not state who paid for it.
DuBois J, Dover JS, Jones TM, Weiss RA, Berk DR, Ahluwalia G. Phase 2 randomized, dose-ranging study of oxymetazoline cream for treatment of persistent facial erythema associated with rosacea. J Drugs Dermatol. 2018;17(3):308-316.