Why is concomitant use of Ogsiveo (nirogacestat dihydrobromide) with proton pump inhibitors or H2 blockers not recommended?

Proton pump inhibitors and H2 blockers are not recommended with Ogsiveo because nirogacestat has substantially reduced solubility above pH 6.0, so these agents may reduce its bioavailability, although their effects on exposure have not been evaluated in a clinical study.