
Cats Meow, thanks again for uploading another fascinating pill imprint!
According to the OP and photographer, the pill is a Canadian 5 mg prednisolone prescribed for her cat. But the corticosteroid is not helping.
Per Health Canada, the only tablets containing the ingredient prednisolone is a veterinary med called DELTA-ALBAPLEX TABLET and a human med called Medrol. All other approved prednisolone substances are ointments or solutions.
The name Delta Albaplex makes sense - the Greek letter delta is a triangle. But the significance of the circle eludes me!
Unfortunately I can't find confirmation of the description.
If the tablet is Delta Albaplex, it's not 5 mg prednisolone.
Delta Albaplex contains three ingredients:
NOVOBIOCIN (NOVOBIOCIN SODIUM) 60mg
PREDNISOLONE 1.5mg
TETRACYCLINE HYDROCHLORIDE 60mg
The tablet is prescribed to DOGS for acute or chronic upper respiratory conditions.
I did read something the other day that stated it's not to be used for CATS. But I can't find that reference this evening.
There is a .pdf link to the prescribing info (no description) but my browser won't let me insert the link. Search for the 4th or 5th result for Delta Albaplex on Google, and you can read the package insert.

Thanks for the follow up Kirby, interesting. It sure is a cool looking pill imprint, clean and simple. Notice one line is broken and it melds into the circle.