You need to read up on patents, expiration of patents, and generics. Then you will understand why new drugs are expensive and why later they become cheap. Clozaril, the first atypical antipsychotic historicalaly, is much, much older than Zyprexa. Clozaril is older by decades. So of course when Zyprexa was the new kid on the block, Clozapine was probably alreaydy off patent and generics are cheap. Now you can buy generic olanzapine but there is no generic for Lybalvi which was approved, if my memory does not fail me, in 2021.