Activist hedge fund firm Starboard Value has built a $1bn position in Pfizer and is planning to push for strategic changes at the pharmaceutical giant as the company grapples with declining post-pandemic revenues, according to a report by the Wall Street Journal.

Folloiwng the investment, which equates to a 0.6% stake in the business, Starboard want to see changes aimed at reviving Pfizer's share price, which has plummeted by nearly 54% since its pandemic-era peak.

The report cites unnamed sources as revealing that the US hedge fund has enlisted the expertise of former Pfizer executives, including ex-CEO Ian Read and former CFO Frank D’Amelio, to chart a path forward, although the exact details of Starboard’s proposed strategy remain unclear.

Despite its role in producing one of the world’s most successful Covid-19 vaccines, Pfizer has struggled to sustain its momentum as demand for Covid-19 products wanes. The company's stock is currently trading significantly below its all-time high from December 2021, when pandemic-related sales drove record revenue, with its current market capitalisation standing at approximately $162bn.

Pfizer has been attempting to address its challenges, including weaker sales of its Covid-19 treatments, the disappointing launch of its respiratory syncytial virus (RSV) vaccine and setbacks involving its weight-loss drugs which contributed to a 41% year-over-year fall in revenue in 2023.