BERLIN, Nov 3 (Reuters) - Germany's health minister defended on Tuesday his decision to purchase additional supplies of remdesivir for treating COVID-19, saying Gilead's antiviral drug was useful especially early in the course of the disease.

"Because it makes sense in some situations and because the need has risen enormously we have procured additional supplies of remdesivir," Jens Spahn told a news conference.

Germany said on Monday that it has requested around 5% of the supply of remdesivir under a six-month European Union supply deal with Gilead, despite criticism of the deal due to a lack of evidence about the drug's effectiveness in treating COVID-19.

Medical experts have called on Brussels to renegotiate the 1 billion euro ($1.17 billion) deal agreed last month after remdesivir showed poor results in a large trial conducted by the World Health Organization.

Uwe Janssens, head of the German DIVI association for intensive care medicine, said the WHO's Solidarity Trial on remdesivir had not yet been peer reviewed by external experts.

"This is a reason for us to look at it cautiously," he said, adding however that he believed it did make sense to use the medicine in the early stages of treatment.

Swiss doctors told Reuters that they were also continuing to use remdesivir in hospitals. ($1 = 0.8543 euros) (Reporting by Caroline Copley and Andreas Rinke; Additional reporting by John Miller; Editing by Susan Fenton)