TrenibotulinumtoxinE alone smoothed frown lines within hours, but faded by day 21

TrenibotulinumtoxinE met a strict frown-line goal at day 7 in 60.0% of adults vs. 0.6% with placebo, with an effect that started at hour 8 and faded by day 21, in a phase 3 trial published Oct. 24, 2026, in Aesthetic Surgery Journal. It offers a short-lived choice among aesthetic treatments.

Botulinum toxin injections are among the most popular cosmetic treatments for the “11” lines between the eyebrows, called glabellar lines. The usual products, based on botulinum toxin type A, take a few days to work and last months, which makes some first-timers nervous about committing. TrenibotulinumtoxinE, or trenibotE, is a type E toxin designed to work fast and wear off quickly.

What did the trial test?

Adults with moderate to severe frown lines, both people who had used toxins before and people who never had, were assigned by chance, three to one, to trenibotE (700 U) or placebo. Neither participants nor doctors knew which. To count as a success, the line had to reach none or mild, with at least 2 grades of improvement at maximum frown, judged by both the doctor and the participant at day 7.

What did the study find about aesthetic treatments?

Improvement began as early as hour 8, peaked at day 7 and returned to moderate or severe lines by day 21. Most side effects were mild, not serious and unrelated to treatment.

Why does this matter?

A toxin that works within hours and fades in about three weeks could serve people who want to try the effect before committing to a longer-lasting product, or who need a quick result for an event. It also gives doctors a different tool from type A toxins.

How solid is this evidence?

For what it measured, it’s strong. Mongevity rates it A on our A-to-E scale: a pivotal double-blind, placebo-controlled phase 3 trial. Limits: the abstract doesn’t give the number of participants, comparison was with placebo rather than with type A toxins, and the study was aimed at approval of the product.

What does this mean for you?

If you’re considering frown-line injections, ask a qualified physician about the options, how long each lasts and the possible side effects. A short-acting option may be a way to try, but it’s still a medical procedure and should be done by trained professionals.

How do I explain this at dinner?

There’s a new kind of botulinum toxin for frown lines that starts working the same day and wears off in about three weeks. In a trial, most people treated with it hit a strict goal at one week, while almost no one on placebo did. A good question for the table: would you rather try something short first?

In one sentence: trenibotulinumtoxinE smoothed frown lines within hours, with an effect that faded by day 21, in a pivotal phase 3 trial.