A randomized, active- and vehicle-controlled, multi-site, double-masked study to evaluate the safety and tolerability of QLS-111 versus vehicle in subjects with primary open-angle glaucoma or ocular hypertension. Primary objective is to evaluate the ocular and systemic safety and tolerability of 3 concentrations of QLS-111 compared to vehicle control. Secondary objective is to evaluate the ocular hypotensive efficacy of 3 concentrations of QLS-111 with once daily morning (QAM), once daily evening (QPM), and twice daily (BID) dosing versus vehicle with QAM, QPM, and BID dosing.