Which characteristic is indicative of a drug that is highly protein-bound and has a high molecular weight?

A drug that is highly protein-bound and has a high molecular weight typically exhibits a low volume of distribution. This is because such drugs tend to remain in the vascular compartment rather than distributing widely into tissues. High protein binding means that a significant portion of the drug is attached to plasma proteins, which prevents it from freely moving into extravascular spaces. Additionally, high molecular weight compounds are usually too large to easily permeate cell membranes or diffuse across barriers such as the blood-brain barrier, further limiting their distribution.

On the other hand, rapid distribution, unchanged excretion in urine, and high clearance rates are usually associated with drugs that are low in molecular weight and have lower protein binding. Thus, these characteristics would not apply to a drug known for being highly protein-bound and having a high molecular weight.