variable help. delete string after 3rd comma

Hi Guys,

I have a column as such in a report:

45 L, xyz, abx, alalalalalalla

740 L, abcd, hyr, alspdifkala;

2050 L, adl, pzs, prajdlap

I need to remove all data after that 3rd comma.

45 L, xyz, abx

740 L, abcd, hyr

2050 L, adl, pzs

Can anyone help?

Thanks