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efficacy

[ef-i-kuh-see] / ˈɛf ɪ kə si /


Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The company reported positive results for two studies of its elecoglipron experimental drug, which showed competitive efficacy with a standard safety profile, the analysts say.

From The Wall Street Journal • Jun. 9, 2026

Leerink noted that the efficacy of the study exceeded the firm’s expectations, meaningfully de-risking the drug combination strategy.

From Barron's • Jun. 8, 2026

The analysts at Citi also highlighted what they said were real-world signals of waning efficacy in Wegovy pill as roughly a quarter to a third of patients are no longer losing weight.

From MarketWatch • Jun. 8, 2026

Leaving efficacy to doctors would help Americans lead longer, healthier lives.

From The Wall Street Journal • Jun. 1, 2026

“Himself not especially susceptible to flattery except in a sentimental way, he soon learned its efficacy when plastered thick on big business men,” Sullivan wrote.

From "The Devil in the White City" by Erik Larson




Vocabulary lists containing efficacy


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