QLS-111

QLS-111 is a small-molecule eye drop from privately-held Qlaris Bio that lowers intraocular pressure (IOP, measured in millimeters of mercury, or mmHg; normal range roughly 10 to 21 mmHg) by targeting episcleral venous pressure (EVP), the back-pressure in the veins that drain the eye. In February 2025 Qlaris reported positive Phase 2 topline data from two trials in primary open-angle glaucoma (POAG) and ocular hypertension (OHT), including a 3.7 mmHg mean reduction from a baseline of 23.0 mmHg at the 0.015% once-daily dose in the Osprey monotherapy study (NCT06016972), and 3.2 to 3.6 mmHg additional reduction on top of latanoprost in the Apteryx combination study (NCT06249152), with no clinically meaningful hyperemia and no serious adverse events [1][2]. A second Phase 2 pilot in normal tension glaucoma (NTG), the subset where the optic nerve continues to deteriorate despite IOP inside the normal range, is completed on ClinicalTrials.gov (NCT06030193, n=37) but the company has not yet publicly reported those results [3]. A fixed-dose combination study (NCT07354516, n=60) and a posterior segment perfusion mechanism study (NCT07354477) are ongoing [4][5]. Qlaris closed a $24 million Series B in April 2024, co-led by Canaan and New Leaf Venture Partners [6].

QLS-111 is a novel investigational compound, never approved anywhere. Development sits in Phase 2. The POAG/OHT dose-ranging Osprey study (NCT06016972) and the NTG pilot (NCT06030193) are both listed COMPLETED on ClinicalTrials.gov, and the fixed-dose combination trial (NCT07354516, n=60) is active-not-recruiting [3][4]. A small vascular mechanism study (NCT07354477) is recruiting to look at posterior segment blood flow, the pathophysiology most invoked to explain NTG damage [5]. The Apteryx combination-with-latanoprost study (NCT06249152, n=36) has completed with positive topline data reported in February 2025 [1][2]. No FDA breakthrough, fast track, orphan, or Regenerative Medicine Advanced Therapy (RMAT) designations have been publicly disclosed, which is expected for a small-molecule ophthalmology asset outside of rare disease. Qlaris has not published a Phase 3 initiation date. Based on the FDC study being the most advanced construct and the positive Phase 2 monotherapy readout, a key program in POAG/OHT is the logical next step, with NTG likely to follow as a differentiated label expansion if the NTG pilot data (still not disclosed) supports it. Timelines beyond that are not disclosed by the company.

Aqueous humor is the clear fluid that fills the front of the eye. It is made continuously and must drain continuously; when drainage falls behind, pressure rises and the optic nerve is squeezed. Most of that drainage passes through the trabecular meshwork (TM), then into a ring-shaped vessel called Schlemm's canal, and finally out through the episcleral veins on the surface of the eye. Qlaris describes QLS-111 as an ATP-sensitive potassium channel (K_ATP) modulator that relaxes vessels of the vascular and vascular-like tissues distal to the trabecular meshwork, reducing distal outflow resistance and lowering episcleral venous pressure (EVP) [2]. EVP is the back-pressure in those drainage veins, and no approved glaucoma drug primarily targets it, which is Qlaris's core first-in-class claim. This distinguishes QLS-111 mechanistically from netarsudil (Rhopressa), a Rho kinase inhibitor that acts upstream at the trabecular meshwork by relaxing TM cells' actin cytoskeleton to reduce inflow resistance into Schlemm's canal [7]. Both drugs increase conventional outflow, but the cellular targets and the segment of the drainage pathway they act on are different; the shared effect is downstream, not the mechanism itself. K_ATP channels are the same class opened by cardiovascular drugs like minoxidil, where opening them dilates blood vessels. That cross-tissue biology is what motivates the NTG hypothesis: if QLS-111 dilates vessels supplying the optic nerve head as well as those in the outflow pathway, it could improve posterior segment perfusion and protect the optic nerve independent of any IOP effect. That is exactly what the NCT07354477 pilot is designed to test [5], and if it replicates it would give QLS-111 a mechanistic story no other IOP-lowering drug can tell in NTG.

The two publicly-read-out Phase 2 studies are the anchor of the current data package. Osprey (NCT06016972, n=62 evaluable) was a masked, randomized, vehicle-controlled study assessing safety, tolerability, and IOP-lowering across a dose range in POAG and OHT; safety and tolerability was the primary endpoint, with IOP change as the key efficacy secondary [4]. The 0.015% once-daily dose produced a 3.7 mmHg mean reduction from a mean diurnal baseline of 23.0 mmHg, with no clinically meaningful hyperemia and no serious adverse events [2]. Apteryx (NCT06249152, n=36) tested additive IOP lowering on top of latanoprost monotherapy (baseline 19.8 mmHg), and reported 3.2 mmHg additional reduction at 0.015% once-daily and 3.6 mmHg at 0.015% twice-daily; no incremental hyperemia was observed when added to latanoprost [1][2]. The NTG pilot NCT06030193 (n=37, completed) used a safety-primary design with IOP as secondary [3]; Qlaris has not yet publicly reported its data, which is a real gap for the NTG thesis. The fixed-dose combination study NCT07354516 (n=60, active-not-recruiting) uses change from baseline in IOP as the primary endpoint, which is what a regulator will actually want to see for a key-supporting readout [4]. Enrollments are small and none of these are key-scale, but the Osprey vehicle-control arm gives the Phase 2 efficacy claim a locked comparator rather than pure within-subject change.

Our model estimates a 3% chance this drug is eventually approved. It starts from the historical base rate for Phase 2 drugs in this area (about 27%), then adjusts using ten facts about the trial and sponsor. What moves the number most: it is held back by heavier-than-usual blinding, the sponsor's thin or weak approval record, weak or limited earlier-phase results, and a randomized design. The other facts land near average for this stage, so they leave the estimate roughly where the base rate put it.

Efficacy risk in NTG remains the largest single concern. NTG is defined by patients whose IOP is already in the normal range, so proving that further lowering IOP protects the optic nerve is a long, expensive endpoint that requires visual field progression data over years, not months. If Qlaris pursues an NTG-specific label, the key trial is a multi-year commitment, and the NTG pilot data that would justify starting it has not been publicly disclosed. For POAG/OHT the efficacy risk is lower after the Osprey readout, but the 3.7 mmHg monotherapy reduction is competitive with, not clearly superior to, netarsudil (roughly 3.3 to 5.0 mmHg in RITE/ROCKET keys) and well below prostaglandin analogs (typically 5 to 8 mmHg). FDA has historically approved glaucoma drugs on non-inferiority to active comparator or on clinically meaningful IOP reduction of roughly 2 to 3 mmHg versus placebo, so the magnitude is above the regulatory floor but not differentiated on efficacy alone. On safety, K_ATP openers dilate vasculature systemically, and the oral class carries a history of tachycardia and hypotension; topical ocular delivery has so far avoided this, and Phase 2 showed no meaningful hyperemia (in contrast to what limited uptake of netarsudil) [2][7]. Execution risk is real: Qlaris is a private single-asset company with a $24 million Series B closed in April 2024 [6]; running a Phase 3 glaucoma program requires either substantial additional financing or a strategic partner. Commercial risk is the payer question. Generic latanoprost costs pennies per bottle, so any new IOP-lowering drop has to justify its price. QLS-111's differentiated angle, if it holds, is EVP targeting, additive benefit on top of PGAs, and the NTG posterior-flow story, none of which is well-served by generics.

Worth watching, and the signal-to-noise ratio just improved. The February 2025 Osprey and Apteryx readouts converted QLS-111 from an unproven mechanism into a Phase 2 asset with a real IOP effect and a clean safety profile [1][2]. The two remaining catalysts that would separate it from the graveyard of me-too glaucoma drops are the FDC study readout (NCT07354516) and the posterior perfusion pilot (NCT07354477). Qlaris is a Series B-stage private company with a narrow single-asset pipeline and $24 million raised in April 2024 [6], which means the next 18 months are effectively binary: either the Phase 2 package supports Phase 3 initiation (and probably a strategic partnership announcement) or the program stalls on financing. Check back after the active-not-recruiting FDC trial posts results, and specifically watch for a Phase 3 registration on ClinicalTrials.gov and for Qlaris to disclose the NTG pilot data, which remains the single largest data gap on the NTG thesis. The NTG angle is the interesting long-term story because no glaucoma drug has ever been developed and labeled specifically for that population, and if the posterior blood flow mechanism replicates, QLS-111 would have a genuinely differentiated pitch to prescribers rather than a fifth entrant in a crowded IOP-lowering field.