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NMPA Review Report Released for Ivantis’ Hydrus Microstent

The NMPA granted innovation approval to Ivantis, Inc.’ hydrus microstent and issued a review report.

This is the fifth report published for overseas manufacturers, after Medtronic, CarboFix Orthopedics, Intuitive Surgical and Abbott.

The published review reports like this one serve as important references for you to understand what the regulatory authorities are thinking and evaluating during their review process. We have been following the list for the past several years and review the relevant ones for our clients’ specific products to gain more clarity and be more efficient in their submission and approval process. As NMPA standardizes and streamlines the review process for fast-track approval, domestic and overseas players can benefit from our expertise and experience.

Product Description, Pre-clinical and Clinical

  • Product structure and composition
  • Intended Use

This product is suitable for patients with primary early to moderate open-angle glaucoma who are unable to tolerate or are unsuitable for traditional filtering surgery, and who, under static gonioscopy, have fully open angles, have had inadequate response or are intolerant to medication alone, and for whom angle laser therapy cannot control disease progression or is deemed inappropriate by the physician. It is also intended for patients who cannot undergo or are ineligible for angle laser therapy, and who require intraocular pressure (IOP) reduction in conjunction with cataract surgery.

  • Model/Specification
  • Working principle


  • Product Technical Requirements (PTR) research
  • Product Performance Evaluation

Product performance evaluation includes austenite completion transformation temperature, magnetic resonance imaging compatibility, finite element analysis, leachables studies, nickel elution, hydrolysis stability, cadaveric corneal edge simulation usage, and cadaver eye fluid dynamics coefficient, among others.

  • Biocompatibility

The glaucoma drainage device in the product composition is considered an implantable device in prolonged contact with tissue, while the delivery device is an external access device in short-term contact with tissue. The applicant has conducted a biological evaluation of the glaucoma drainage device and delivery device according to the GB/T 16886 series standards. The biocompatibility risk of the product is deemed acceptable.

  • Animal study

The applicant conducted ocular implantation trials in crab-eating macaque, evaluating indicators such as fundus examination, intraocular pressure (IOP) measurement, scanning electron microscopy, and observations using optical microscopy. The results demonstrated that postoperatively, all animals’ IOP returned to the normal range, there were no morphological changes in the implanted ocular tissues, and the implants exhibited good tolerance within the anterior chamber of the eye.

The review report also describes the sterilization study, and product shelf life and packaging study, software study. If you are interested in any aspect, please email us at, and we will translate the contents for you.


The applicant conducted the clinical evaluation by submitting overseas clinical trials data. The clinical trial was prospective, randomized, double-blind, and parallel-controlled. The experimental group underwent cataract surgery with implantation of the investigational product, while the control group underwent cataract surgery alone. A total of 556 subjects were planned to be enrolled (369 in the experimental group and 187 in the control group). The primary efficacy endpoint was the proportion of eyes with a reduction of at least 20% in average daytime intraocular pressure (IOP) from baseline after medication washout at 24 months, with the response rate of the experimental group compared to a target rate of 50%. Secondary efficacy endpoints included the average change in IOP. Safety evaluation focused on adverse events.

Results showed that at 24 months postoperatively, the proportion of eyes with a reduction in IOP from baseline was 77.2% in the experimental group and 57.8% in the control group, with a difference of 19.5% (95% confidence interval [CI]: 11.2% to 27.8%), indicating superiority. The 24-month response rate of the experimental group was within a 95% CI of 72.6% to 81.4%, exceeding the target rate of 50%. Additionally, the average reduction in daytime IOP from baseline was 7.5 mmHg in the experimental group and 5.3 mmHg in the control group, with a statistically significant difference between groups. Safety results showed no significant difference in adverse events between the experimental and control groups.

Furthermore, the applicant provided clinical follow-up data up to 5 years after overseas marketing approval. Among the available subjects in the experimental group (308 cases), 201 maintained non-medicated control with an average IOP of 16.6 mmHg, while in the control group, 61 subjects maintained non-medicated control with an average IOP of 17.6 mmHg. The experimental group showed an average IOP reduction of 8.3 mmHg compared to 6.5 mmHg in the control group. No significant differences were observed in safety outcomes between the two groups.

Please email us at to see if NMPA released review reports for your device. We can translate for you with nominal fees.