A Study in Adult Males With X-linked Congenital Nephrogenic Diabetes Insipidus to Test the Effects of NDI-5001 Given for Multiple Days and to Test How NDI-5001 is Tolerated and Taken up in the Body

The primary purpose of this trial is to evaluate the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of NDI-5001 administered as a capsule following daily oral dosing in adult males with X-linked congenital nephrogenic diabetes insipidus (NDI) due to vasopressin receptor Type 2 (V2R) mutations.

Inclusion Criteria 1. X-linked congenital NDI with a genotype-confirmed arginine vasopressin receptor 2 (gene) (AVPR2) mutation and no mutation in aquaporin-2 (AQP2). 2. Urine osmolality of ≤ 200 milliosmoles per kilogram of water (mOsm/kg) in a spot urine sample obtained from a first morning void upon awakening (at screening, check-in \[Day -4\], and Day -1) before consuming any food or drink after awakening. 3\) BMI between 18.0 to 32.0 kilograms per square meter (kg/m\^2), inclusive. Exclusion Criteria 1. Participant who is not willing to follow a low-sodium (\