First patient dosed in Qlaris Bio's phase 2 Nightingale clinical trial for QLS-111

With the Nightingale study taking place in South Korea, the trial will have access to a large NTG patient population due to the disease’s high prevalence in Asia. Image credit: AdobeStock/RFBSIP

The first patient has been dosed in Qlaris Bio’s Phase II Nightingale clinical trial for QLS-111 in patients with normal tension glaucoma (NTG).¹ The study, which is Qlaris Bio’s third phase 2 clinical trial of the company’s lead investigational therapy, will be evaluating the safety, tolerability, and efficacy of QLS-111 in adult patients with NTG and will be conducted at multiple clinical sites across South Korea, according to a news release.

“NTG is highly prevalent in Asia and many of our patients struggle with ongoing vision loss despite intraocular pressures (IOP) that appear ‘normal’ by conventional standards,” said Ki Ho Park, MD, PhD, professor of ophthalmology at Seoul National University College of Medicine and lead investigator of the Nightingale study, in the release. “We are excited to evaluate QLS-111. A therapy that targets episcleral venous pressure (EVP) may offer a much-needed new strategy for pressure reduction and disease control in this population.”

QLS-111 is a first-in-class ATP-sensitive potassium channel modulator designed to lower IOP by reducing EVP. Qlaris Bio noted that this therapy is particularly relevant for patients with NTG whose IOPs remain within a healthy range but continue to experience disease progression.¹

With the Nightingale study taking place in South Korea, the trial will have access to a large NTG patient population due to the disease’s high prevalence in Asia, the release stated.¹

“The initiation of the Nightingale study is an exciting milestone in our mission to address unmet needs in glaucoma,” said Thurein Htoo, CEO of Qlaris Bio, in the release. “We believe that targeting EVP is a fundamentally new and important mechanism that can benefit many patients worldwide, especially as a complement to other therapies for patients requiring further IOP control without added side effects, such as hyperemia.”

The study also will work to build on positive clinical data that was a result of previous phase 2 Osprey and Apteryx clinical trials. Both trials “demonstrated promising safety and efficacy of QLS-111 in patients with ocular hypertension and open angle glaucoma, including when administered in combination with latanoprost,” the release stated.¹

Osprey and Apteryx trial data was released by Qlaris Bio in February, with the Osprey study demonstrating that the 0.015% concentration dosed once daily in the evening drove the greatest decrease in IOP, as seen in the mean reductions of 3.7 mmHg from mean diurnal baseline IOP of 23.0 mmHg. The Apteryx trial found that QLS-111 0.015% dosed with latanoprost demonstrated additive mean IOP reductions when compared to latanoprost monotherapy, and achieved a 3.2 mmHg greater reduction for QLS-111 QPM dosing and 3.6 mmHg greater reduction for QLS-111 twice daily dosing.²

In recent news, Qlaris Bio announced in June that a QLS-111 and latanoprost fixed-dose combination (QLS-111-FDC) is in development for the treatment of primary open-angle glaucoma, ocular hypertension, and normal-tension glaucoma in patient whose optimal IOP control may remain “unachievable” due to needing an EVP reduction. The novel preservative-free therapy demonstrated a more than 33 mm Hg of additional IOP reduction compared with latanoprost monotherapy alone, according to the phase 2 clinical study data. Additionally, no incremental hyperemia was observed when QLS-111 0.015% was added to latanoprost.³

References:

1. Qlaris Bio announces first patient dosed in phase 2 Nightingale clinical trial in normal tension glaucoma patients. News release. August 26, 2025. Accessed August 26, 2025.

2. Joy J. Positive topline results from Qlaris Bio phase 2 clinical trials find QLS-111 demonstrates IOP-lowering activity in patients with POAG, OHT. Optometry Times. February 5, 2025. Accessed August 26, 2025. https://www.optometrytimes.com/view/positive-topline-results-from-qlaris-bio-phase-2-clinical-trials-find-qls-111-demonstrates-iop-lowering-activity-in-patients-with-poag-oht

3. Filkins K. Qlaris Bio announces development of QLS-111-FDC. Optometry Times. June 13, 2025. Accessed August 26, 2025. https://www.optometrytimes.com/view/qlaris-bio-announces-development-of-qls-111-fdc