Theranos Limits Use of Blood Test Technology

Theranos, the clinical lab company revolutionizing its industry with low-cost finger-prick tests, is limiting the use of its tiny blood vials to assays approved by the US Food and Drug Administration (FDA), company CEO Elizabeth Holmes said yesterday.

Of the 250-plus tests that Theranos performs, only one — for herpes simplex virus-1 immunoglobulin G — is FDA-approved. But more tests are in the regulatory pipeline. […]

In a follow-up story, the WSJ reported that Theranos recently stopped collecting finger-prick blood samples in its patented Nanotainer vials except in its herpes simplex test after the FDA conducted a surprise inspection and declared the vials to be unapproved medical devices. The FDA approval of the Theranos test for herpes simplex, in contrast, included the Nanotainer.

An FDA spokesperson told Medscape Medical News that she could not comment on whether the agency had cracked down on Theranos as reported.

Laboratory Developed Tests in the Spotlight

The FDA has indicated publicly that it seeks to more tightly regulate in vitro tests used by the likes of Theranos. In vitro diagnostic tests that manufacturers sell to end users, such as clinical labs or patients, must be FDA-approved. But what Theranos relies on are “laboratory developed tests” (LDTs), which are designed, manufactured, and used in-house. Traditionally, the FDA has not required LDTs to obtain FDA approval — an example of “enforcement discretion” — because they were relatively simple tests and not widely available.

However, LDTs have “proliferated significantly” since the FDA gained authority to regulate all in vitro tests as medical devices in 1976, the agency states on its website. In addition, more complex LDTs on the scene diagnose conditions such as cancer and Alzheimer’s disease, not just a patient’s vitamin levels. When such higher-risk LDTs make a mistake, patients can suffer serious if not deadly consequences. […]

The question of whether the FDA should regulate LDTs is a hot topic in Congress, said Diana Zuckerman, PhD, president of the National Center for Health Research, a think-tank focused on women, children, and families, in an interview with Medscape Medical News. Some lawmakers, said Dr Zuckerman, believe excessive regulation is discouraging innovation. Others fear laxity that will permit unsafe, ineffective products to reach the market. Dr Zuckerman favors a more cautious approach to LDTs.

“There’s so much excitement about these tests, but the scientific evidence of how well they work is lacking,” said Dr Zuckerman.

Read the full article here.