Spadaccino becomes the fourth director to quit Cohn & Wolfe in the past year.
She will join Pegasus next week as a director of the agency’s fast-growing pharma and life sciences division.
At Pegasus, Spadaccino will be responsible for leading PR and healthcare professional education campaigns for the agency’s existing pharma and consumer health clients. She will also have responsibility for driving pharma new business in the UK and international markets.
Spadaccino’s departure follows the settlement of a high-profile court case brought by Cohn & Wolfe against three former healthcare directors earlier this year.
Fiona McMillan, Rebecca Galbraith and Jeremy Clark apologised in April and the case was settled out of court.
Spadaccino was one of five directors on a board leading the healthcare team that was created in February after long-time healthcare MD Jacinta Collins announced she was leaving.
The board also included McMillan, Galbraith and Annabel Fiddian-Green, who left the agency last year.
A fifth healthcare director, Alison Wright, remains at Cohn & Wolfe.
The agency has since sought to bolster its healthcare team with the appointment of Catherine Barnett as a board director and Mike Kan as global healthcare practice leader.