Texture does not render properly at small size

Hello,

I have the following texture from an icon pack on the marketplace:

99c3745f7b43794528ec86cffdf030b2.png

It’s a continuous circle with one pixel of transparent padding. It’s imported with the following settings:

I have then created a material to mask based on a scalar. This works perfectly fine at the default previews size:

However, when I preview it at the size it’s going to be in-game, I see the following artifacts:

Note how the circle is now rendering as if it were a dotted circle. The same effect occurs in-game, both when I directly have UMG render the texture, and when I render the material. Is there any way to get the engine to render it properly at small sizes?

Thanks!