Pippa was all smiles as she walked the red carpet and posed for photos at the event, which was being hosted by Made In Chelsea star Spencer Matthews.
The brunette beauty stunned in an all-red ensemble, which consisted of a long-sleeved top and matching pants, which she teamed with a contrasting pair of navy pointy-toed heels.
Her barely-there makeup look showed off her incredibly youthful visage, and she wore her voluminous tresses in loose flowing waves.
Pippa completed her chic red-carpet look with an understated pair of blue dangling earrings and a cerulean clutch.
The glitzy affair was to launch the company’s new low-calorie range of drinks, which includes a 1.2 per cent bottle of “clean gin”.
Speaking to British GQ, Spencer said: "You’d need to drink 31 clean gin and tonics to compare a single normal gin and tonic. There’s more alcohol content in bread."
Pippa’s appearance comes after her brother James opened up about his depression in a candid post to his Instagram, which he shared with a photo of himself, his fiancée and their dogs.
“Today I wanted to say thank you. Thank you for the incredible support shown towards my speaking publicly about my illness. Depression,” he said.