Company: SNY
Filing Date: 2025-10-27
Form Type: 424B5
Source: 0001193125-25-250786
Chunk: 20

Company: Sanofi
Filing Date: 2025-10-27
Form: 424B5
Chunk 20
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 provide them with a yield comparable to similar investments that might have developed greater market acceptance, and may consequently suffer from increased pricing volatility and
market risk.

The interest rate on the floating rate notes is based on a Compounded SOFR rate and the SOFR Index, both of which have a limited history in the marketplace.

For each interest period with respect to the floating rate notes, the interest rate is
based on Compounded SOFR, which is calculated using the SOFR Index published by the Federal Reserve Bank of New York according to the specific formula described under “Description of the Notes—Interest—Floating Rate Notes,”
not the SOFR rate published on or in respect of a particular date during such floating rate notes interest period or an arithmetic average of SOFR rates during such period. For this and other reasons, the interest rate on the floating

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rate notes during any floating rate notes interest period will not be the same as the interest rate on other SOFR-linked investments that use an alternative basis to determine the applicable
interest rate. Further, if the SOFR rate in respect of a particular date during a floating rate notes interest period is negative, its contribution to the SOFR Index will be less than one, resulting in a reduction to Compounded SOFR used to
calculate the interest payable on the floating rate notes on the floating rate interest payment date for such floating rate notes interest period.

Compounded SOFR with respect to a particular interest period will only be capable of being determined near the end of the relevant interest period.

The level of Compounded SOFR applicable to a particular interest period and, therefore, the amount of interest
payable with respect to such interest period will be determined on the floating rate interest payment date (as defined herein) for such floating rate notes interest period. Because each such date is near the end of such interest period, holders of
the floating rate notes will not know the amount of interest payable with respect to a particular interest period until shortly prior to the related floating rate interest payment date, and it may be difficult for holders of the floating rate notes
to reliably estimate the amount of interest that will be payable on each such floating rate interest payment date. In addition, some holders of the floating rate notes may be unwilling or unable to trade the floating rate notes without changes to
their information technology systems, both of which could adversely impact the liquidity and trading price of the floating rate notes.

The SOFR Index may be modified or discontinued and the floating rate notes may bear interest by reference to a