Sept 18 Reuters Contract drug manufacturer Lonza said on Monday Chief Executive PierreAlain Ruffieux will leave the Swiss company by mutual agreement at the end of the month, weighing on investor confidence about the group39;s mediumterm profit prospects.

Lonza said its mediumterm strategy and outlook would be discussed in detail at its capital markets day on Oct. 17 and that Chairman Albert Baehny would take on the CEO responsibilities until the appointment of a permanent successor to Ruffieux.

Shares in Lonza, which makes drug ingredients for healthcare and biotech companies, dropped 5.3 shortly after the 0700 GMT market open, trading near an eightmonth low.

The stock has been down since Lonza cut its 2023 earnings outlook in July, citing weak demand for capsules for dietary supplements and warning that biotech customers were pursuing fewer projects in early stage drug development and in cell and gene therapy.

At the time, it also lowered its operating profit margin target for 2024 to 3133 from 3335.

A former Roche executive who joined Lonza in 2020, Ruffieux oversaw the company39;s role in producing COVID19 vaccines for Moderna during the pandemic.

He was also behind a multiyear investment push to assist drug developers working on new therapeutic proteins as well as cell and gene therapies.

That was funded in part through the 2021 sale of Lonza39;s speciality chemicals business to private equity investors for 4.2 billion Swiss francs 4.69 billion in 2021.

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