Probably it should be "The", but it is not possible to be certain without more context. The choice between "a" and "the" typically depends on whether the reader already knows which one you are referring to, so it can be hard to judge in isolation. "CD (controlled drug) copy for Zomoph" doesn't make obvious sense to me.
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Jigneshbharati A separate copy i.e written for a controlled drug.I think I need more background context to understand this. Do you mean a copy of a document that has previously been mentioned? Some kind of "base" document exists, and then a separate version is made for a controlled drug?