Defined as: "a drug which directly impacts the course of disease progression with beneficial consequences to a patient"
This seems an awful lot like a drug that modifies a disease. It is certainly not a set phrase as a large range of semantically appropriate NPs can substitute for drug, such as Alzheimer's disease drug, treatment, medication, therapy, potential, etc. and, at least, altering substitutes for modifying. DCDuringTALK 12:31, 5 November 2011 (UTC)
Delete per very reasonable argument above. Mglovesfun (talk) 14:41, 5 November 2011 (UTC)
Delete per nom. bd2412T 17:46, 5 November 2011 (UTC)
Even so, it is a medical term and has value in being included here.Westernstag 03:15, 7 November 2011 (UTC)
Move the content to "disease-modifying", and adjust the definition to make it adjectival, applying to various treatments including drugs. Interesting search: google books:"diseasy-modifying drug" definition. One particular find, among the others: this. The key question for understanding the term is this: disease-modifying as opposed to what? The answer seems to be this: as opposed to merely reducing symptoms. If this answer is correct, it is nowhere clear that this is meant by "disease-modifying" from "disease" and "modifying"; as long as symptoms are part of a disease, a thing that modifies symptoms thereby also modifies the disease. --Dan Polansky 20:18, 7 November 2011 (UTC)
Comment - this is a specific term used in the field. Would additional sources be something which would bring those who have suggested deletion to re-evaluate their opinion, or would this be a futile effort (I don't intend to expend time on futility). --Ceyockey 06:05, 8 November 2011 (UTC)
The literature of the field seem to show "disease-modifying" applying to concepts other than "drug" or "therapy", such as "effect", "gene", "agent", "activity". IOW, it seems to combine freely with a variety of nouns, both in attributive and predicative positions. To me, this is exemplifies the difference between a book's glossary or a specialist technical glossary and a true dictionary. Some others here seem to differ on this point. DCDuringTALK 19:28, 8 November 2011 (UTC)