It is because the government-funded trial was a placebo-controlled, double-blind, randomized controlled trial.

FORBES

Safety data for KYNAMRO are based on pooled results from four Phase 3, randomized, double-blind, placebo-controlled trials with a total of 390 patients of which 261 patients received weekly subcutaneous injections of 200 mg of KYNAMRO and 129 patients received placebo for a median treatment duration of 25 weeks.

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In the double-blind, randomized control trial, half the women got tenofovir gel and half got a placebo.

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