Yes, it does. More or less every class of antibiotic was invented between 1940 and 1960. Discoveries since that period have been mostly incremental.
https://www.nature.com/articles/nature14098
Note that the paper isn't only about a new antibiotic but also about a promising method for making additional discoveries via uncultured bacteria.
In engineering or any scientific field, incremental progress is clearly still progress. For most other kinds of drugs, time doesn't work against their effectiveness. Texts describe the use of aspirin precursors, such as willow teas, dates back over four thousand years to ancient Sumer. Salicylates haven't stopped being effective since then.
The trouble with antibiotics is that resistance inevitably develops over time even if we manage to curb their misuse. It isn't enough to enough to develop new antibiotics, novel or otherwise; to keep the "miracle of antibiotics" alive, we need to continually to develop novel ones.
That hits pretty close to what I think I am seeing here.
There are a few assumptions built in to Eroom's "law" which I think we have learned to avoid when looking at Moore's "law".
One is that we will not come up with an alternate or more effective way to address the problems drugs are currently addressing. Another is that we will not come up with a drastically cheaper or more effective way to invent new novel drugs. Still another is that we will not invent a drastically cheaper or more effective way to verify a drug's usefulness and safety.
With Moore's observation, I think people have learned to assume that any observable slow down will be corrected by the invention of some previously unimaginable technique or other machine that will keep things on track. (nothing really makes this have to be true, but we seem to think of it that way)
Similarly, any number of future inventions could completely reverse Eroom's observation.
As we get better at editing genomes, making nanomachines, and increasing the resolution of 3d printers, previously impossible techniques may suddenly make it easy to invent novel drugs, address the same issues without drugs, or change the game in any number of other hard-to-predict ways.
Given these increasingly plausible possibilities, I am inclined to see Eroom's "law" as the mere observation of a relatively short lived trend in human history.