Activist investor Starboard Value has taken a stake of about $1 billion in Pfizer Inc. and is seeking to spur a turnaround of the struggling pharmaceuticals giant, according to a person familiar with the matter.

Starboard has approached former Pfizer executives Ian Read and Frank D’Amelio to aid in its efforts, and they have expressed interest in helping, the person said, asking not to be identified discussing private information.

Read was Pfizer’s chief executive officer from 2010 to 2018 and chose current CEO Albert Bourla as his successor. D’Amelio was the New York-based company’s chief financial officer from 2007 to 2021.

Starboard’s exact plans and engagement with the company aren’t clear at this time. The activist has found that investors and research analysts are frustrated by the company’s sustained post-pandemic struggles, the person said.

Pfizer and Starboard couldn’t immediately be reached for comment outside normal business hours. The Wall Street Journal reported earlier Sunday on Starboard’s Pfizer efforts.

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