Functional equivalent to GL_LINE_SMOOTH?

Does Vulkan have a method to render antialiased lines like the GL_LINE_SMOOTH setting in OpenGL? I tried using a VkPipelineRasterizationLineStateCreateInfoEXT with the VK_LINE_RASTERIZATION_MODE_RECTANGULAR_SMOOTH_EXT rasterization mode, but the results are not anything like line smoothing in OpenGL.

Actually, the issue is probably the fact that I have switched to using additive blending together with pre-multiplied alpha. Assuming the line rasterization mode listed above does what I want, is there a way to make this play nice with additive blending?

Related: Reminds me of some Vulkan content in the Khronos BOFs at SIGGRAPH. Search down for “OpenGL Line Quality on Vulkan”: