Patient Enrolment in Phase II CIRCLE Study Evaluating THR-409 (ocriplasmin) for Non-Proliferative Diabetic Retinopathy (NPDR) Discontinued due to Slow Recruitment Rate


ThromboGenics NV (Euronext Brussels: THR), a biotechnology company developing novel medicines for back of the eye diseases and focused on diabetic eye disease, today announces that it has discontinued patient recruitment in its Phase II CIRCLE study for Non-Proliferative Diabetic Retinopathy (NPDR), effective immediately, due to the trial's slow recruitment rate.

CIRCLE is a Phase II study evaluating the safety and efficacy of up to three intravitreal injections of THR-409 (ocriplasmin) to induce complete posterior vitreous detachment (total PVD) in NPDR patients, potentially avoiding disease progression from NPDR to proliferative diabetic retinopathy (PDR), a serious sight threatening condition.

Early symptoms of NPDR do not immediately affect a patient's vision, therefore, many of the target patients for this study have few symptoms and so are less aware of their disease. These factors have contributed to the slow recruitment rate and the decision to discontinue study enrolment. Ocriplasmin was found to be generally safe and well-tolerated with no new safety signals raised.

Data from the study will be analyzed and shared with the scientific community via a publication in late 2018/early 2019. ThromboGenics will follow-up with every patient included in the study, as appropriate.

Resources previously earmarked for the CIRCLE study will be re-allocated to progress new drug candidates currently being explored for the treatment of diabetic eye disease into the clinic in 2018.

Patrik De Haes, MD, CEO of ThromboGenics commented:

"Our decision to terminate enrolment in the CIRCLE study is due to the slow recruitment rate, which is primarily due to the patients being unaware of their condition. We remain committed to developing novel therapies for the treatment of diabetic eye disease and look forward to using our redirected resources from this study to progress our current pipeline and to move an additional new drug candidate into the clinic in 2018."


ThromboGenics is a biopharmaceutical company focused on developing innovative treatments for eye disease, with a focus on diabetic eye disease. The company's pipeline of disease modifying drug candidates is targeting the key segments of the diabetic eye disease market.

ThromboGenics' is developing THR-317, a PLGF inhibitor in a Phase I/IIa clinical study for the treatment of diabetic macular edema. Results are expected in Q1 2018. ThromboGenics' late pre-clinical pipeline consists of THR-149, a plasma kallikrein inhibitor, which has resulted from research collaboration with Bicycle Therapeutics, and THR-687, an integrin antagonist, which was in-licensed from Galapagos. THR-149 is expected to enter the clinic in H1 2018 and THR-687 around mid-2018. Further new drug candidates are currently being progressed for the treatment of diabetic eye disease and one of these is expected to enter development in 2018.

ThromboGenics owns the global rights to JETREA® (ocriplasmin), the only pharmacological vitreolysis drug approved for the treatment of symptomatic vitreomacular adhesion (in the US) and vitreomacular traction (in Europe and elsewhere). ThromboGenics is headquartered in Leuven, Belgium, and is listed on the NYSE Euronext Brussels exchange under the symbol THR. More information is available at



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