I've seen a number of Igorot spearheads but they are always symmetrical.
Looks like in that past some non-conformist
Igorot bladesmiths decided to think out of the box! Below are pics of the usual spearheads.
As for the possible practical purpose of such, I'm not sure what it's supposed to accomplish. Looks like the spear is not for throwing as the asymmetrical head will cause the spear to wobble in flight. Hence it's more for close quarters combat I guess.