Accepted answer
25 °C is above the refrigerated band, and how far above is the whole answer. 25 °C is 20 kelvin above the 5 °C middle of a 2–8 °C refrigerator. The ten-degree rule of thumb — degradation rate roughly doubling per 10 K — makes that about 4 times the refrigerated rate, which is an order-of-magnitude statement and not a shelf life. Lyophilised material tolerates this far better than solution does, which is why it is shipped that way, but "tolerates" is a statement about weeks and the vial is being asked about months. Log the excursion rather than guess at it. Nothing here is medical advice, and research-use-only material is not approved for human use.
The honest answer is that ordinary refrigeration handles almost every case people ask about.
Reconstituted with a preservative-containing diluent: refrigerated, conventionally treated as usable for about 28 days from first entry. Without a preservative, single use and discard.
Store with the desiccant sachet if one was supplied, inside the secondary container rather than loose in a drawer. Residual moisture is the dominant variable in solid-state stability.
The 28-day in-use period for preservative-containing multi-dose preparations is printed on the diluent labelling and is a long-standing pharmacy convention.
Appearance does not indicate stability; a normal-looking cake can be substantially degraded.
Keep the desiccant with the vial and the certificate with the lot code.