Eli Lilly & Co employees have accused a factory executive of changing documents required by government regulators to downplay serious quality control problems.

The accusations are alleged to have happened at the drug maker’s US plant which produces Covid-19 treatment, according to an internal complaint.

The unsigned report, reviewed by Reuters after being filed through the confidential employee complaint system, is the latest sign of manufacturing issues at the drug giant.

It says that the executive rewrote findings by technical experts at the plant, which has been under investigation, to make the conclusions more favourable to the firm.

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The confidential source said the findings involved the production of drugs, including the company’s government-funded Covid-19 therapy.

This antibody treatment has been authorised by the US Food and Drug Administration (FDA) for emergency use in combination with a drug for Covid infections in high-risk patients.

Back in March, FDA inspectors found several manufacturing lapses at a Lilly facility in Indianapolis that bottles the Covid-19 therapy.

Problems at the plant included poor sanitation and quality control procedures, according to a preliminary FDA report.

Meanwhile, the company’s chief financial officer resigned in February over what the firm called “inappropriate personal communications” with an employee.

The troubles at the two factories, along with a succession of internal complaints in recent years, deepen the issues facing Eli Lilly & Co, one of the biggest drug makers in the world.

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