For glaucoma surgeons, new devices often arrive in the clinic with little visibility into the regulatory process that brought them there. At the annual meeting of the American Glaucoma Society, Douglas J. Rhee, MD, sought to pull back that curtain, offering a practical overview of how minimally invasive glaucoma surgery (MIGS) devices move through the approval pathways of the US Food and Drug Administration (FDA), and why those distinctions matter long after a device reaches the market.

“The topic of my talk is device approval by the FDA and some of the challenges involved,” explained Dr. Rhee, chair of the department of ophthalmology and visual sciences at University Hospitals/Case Western Reserve University School of Medicine in Cleveland. He emphasized that his remarks reflected a clinician’s perspective rather than formal regulatory expertise, drawing heavily on 2 key articles by Gail A. Van Norman, MD, on FDA oversight of drugs and medical devices.^1,2

Although physicians often express frustration with regulatory timelines, Dr. Rhee noted that FDA oversight has played a critical role in improving patient safety and ensuring that innovation does not outpace evidence. “Before the FDA, there was a lot of innovation, but not a lot of safety. It was more of a snake-oil environment,” he said, referencing early medical device advertising.

He also pushed back on the common perception that the FDA itself dictates the rules of approval. “The FDA does not actually make the rules,” Dr. Rhee said. “Congress makes the rules, and the FDA is charged with enforcing the law.” For clinicians interested in changing how devices are evaluated or reimbursed, that distinction has practical implications for advocacy, he pointed out.

Modern device regulation dates to the Medical Device Amendments of 1976, which expanded FDA authority over medical devices. Since then, approval timelines have diverged significantly between drugs and devices. Citing published estimates, Dr. Rhee noted that drugs take an average of about 12 years to reach approval, compared with roughly 3 to 7 years for devices.

Risk classification is a key aspect of the process. Low-risk Class I devices require registration but little additional review. Class II devices, considered moderate risk, typically follow the 510(k) pathway, which requires manufacturers to demonstrate “substantial equivalence” to an already marketed device. Higher-risk Class III devices must undergo the more rigorous premarket approval (PMA) process, which requires clinical evidence demonstrating safety and effectiveness. “For a 510(k), you’re showing that the device is as safe and effective as something that already exists,” Dr. Rhee said. “For a PMA, you have to conduct studies and prove that it is safe and effective for its intended use.”

In glaucoma, these distinctions have shaped both innovation and evidence generation. Over the past 2 decades, several implantable MIGS devices have received PMA approval, whereas many surgical instruments and canal-based devices entered the market through the 510(k) pathway or required no formal approval at all. Procedures such as trabeculectomy, Dr. Rhee explained, predate modern regulation and were effectively grandfathered in. “It was more of a Wild West environment back then,” he said.

The regulatory pathway, he noted, has downstream consequences. PMA-approved devices are typically supported by Level I evidence, which can provide greater security with payors. In contrast, devices cleared through 510(k) often rely on prospective cohort studies or retrospective data, making them more vulnerable to reimbursement challenges.

One notable exception, Dr. Rhee said, is the predictability seen with trabecular meshwork bypass devices. Preclinical cadaver studies demonstrated that placing additional stents led to greater aqueous outflow and pressure reduction—findings that were later reflected in clinical outcomes. “The preclinical trials were incredibly predictive of what we see in the clinic,” he said.

Looking ahead, Dr. Rhee argued that stronger evidence will be essential for newer devices that lack PMA-level data. “For 510(k) devices, one of the things we need to do is conduct prospective randomized, controlled trials,” he said, describing such studies as critical tools when negotiating with insurers and other payors. GP

References

1. Van Norman GA. Drugs, devices, and the FDA: part 1: an overview of approval processes for drugs. JACC Basic Transl Sci. 2016;1(3):170-179. doi:10.1016/j.jacbts.2016.03.002

2. Van Norman GA. Drugs, devices, and the FDA: part 2: an overview of approval processes: FDA approval of medical devices. JACC Basic Transl Sci. 2016;1(4):277-287. doi:10.1016/j.jacbts.2016.03.009