TOKYO, Jan 31 (Reuters) - Nomura Holdings, Japan's biggest brokerage and investment bank, reported on Wednesday a 24% drop in quarterly net profit due to the absence of a one-off profit a year earlier.

Nomura also said it would buy back up to 4.0% of own shares worth 100 billion yen.

October-December profit came in at 50.5 billion yen ($341.72 million), down from 66.9 billion yen a year earlier, when the bank booked a 28-billion-yen gain from a partial stake sale in an affiliate. ($1 = 147.7800 yen) (Reporting by Makiko Yamazaki; Editing by Kim Coghill)