VIENNA (Reuters) - An unnamed Novartis executive sold 925,400 Swiss francs ($946,000) worth of shares less than three weeks before the U.S. Food and Drug Administration (FDA) announced data from tests of its gene therapy Zolgensma had been manipulated.

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Novartis announced the stock sale by an executive member of the board of directors or a member of the executive committee in a Swiss stock exchange filing dated July 19. The sale was first reported by Swiss newspaper SonntagsZeitung on Sunday.

A Novartis spokesman told Reuters, “As is usual in such cases, the transaction was thoroughly checked beforehand and then approved accordingly. The person in question was not in possession of relevant material information.”

The sale was made after the company had informed the FDA about the data manipulation but before the FDA announced it publically on Aug 6.

Shares in Novartis fell almost 3 percent the day after the FDA announcement.

The FDA said this month that Novartis notified regulators in June - more than a month after Zolgensma had been approved - that some of the early testing data had been manipulated.

The company had been aware of the problems for as long as two months before the drug’s U.S. approval, the FDA said, and Novartis could face criminal or civil penalties.

Novartis said this month that it learned of allegations of data manipulation in mid-March and finished a preliminary investigation into the allegations in early May, confirming data discrepancies and raising data integrity concerns.

The data was used to illustrate comparability between an early version of Zolgensma and the later version of the treatment, which was manufactured using a different process.

The FDA said it does not believe that the manipulation impacts the safety or testing surrounding the version of the drug, which treats spinal muscular atrophy (SMA), the leading genetic cause of death in infants.