Diagnostics & Imaging Washington Editor

Diagnostics maker Merlin Labs (Carlsbad, California) took in a March 9 letter posted to FDA's web site last week, citing the firm for validation lapses as well as a failure to obtain a PMA, a 510(k) or an investigational device exemption for one or more devices. The heavily redacted warning letter also cites corrective action lapses among other miscues, and while the firm's web site indicates the company focuses mostly on tests for malaria and dengue fever, the site also indicates that Merlin offers a diagnostic for an unspecified type A influenza test.

Under the section dealing with validation, FDA states that the company had "no pre-approved validation protocol" for an unspecified diagnostic, and lacked "pre-established acceptance criteria" for at least one process validation. Among the specific functions noted in this heavily redacted citation are equipment cleaning and pouch sealing. The firm's response to the 483 was seen as faulty for one of these manufacturing processes because it was not accompanied by "a process validation protocol with pre-determined specifications and associated test results." According to the warning letter, Merlin indicated that it "visually inspect[s]" the process in question.

The letter cites a failure to validate a change of design, but the brevity of the citation and the degree of redaction leaves little detail other than that the firm asserted that "the design validation and verification data are in the design history file," but the response included no copies of the data.

FDA indicates that the company failed to undertake procedurally required corrective and preventive action for false positives in connection with a diagnostic, the name of which was yet again redacted. The company's response was that the false positives had not been confirmed and that "the lot in question met specifications," stating that its handling of the situation did not constitute a CAPA, but rather were "improvements based on business decisions."

Merlin's troubles for this citation seemed to largely hinge on the fact that a subsequent complaint involved another false positive, which the company apparently had confirmed and which prompted the unspecified changes to the diagnostic. FDA argues that such changes "would appear to constitute a corrective and/or preventive action" rather than just a business-based improvement.

The warning letter also cites Merlin for problems with equipment calibration and device history records, the responses for which were both deemed adequate. However, FDA said it could not evaluate the firm's response for a citation for employee training, and informed the company that its response to a citation for equipment cleaning did not measure up because it lacked specifics on the frequency of cleaning.

At press time, the company had not responded to calls from Diagnostics & Imaging Week for comment.

Respironics recalls apnea monitors

Respironics (Murrysville, Pennsylvania) has announced a voluntary recall of almost 5,000 of the SmartMonitor line of infant sleep apnea monitors. The move is prompted by the discovery that the unit may fail to sound an audible alarm, although no problem has been noted for the alert light on the unit.

The recall, announced April 26, was prompted by a single report of an alarm failure notification and affects units manufactured between Jan. 16 and Nov. 13, 2008. This is classified as a class III recall due to the risk of serious injury or death, and Respironics is pulling back all units in distribution and calling for all units in use to be returned.

CMS no longer to cover CTC for colorectal cancer

The Centers for Medicare & Medicaid Services has confirmed that it will not cover computerized tomography for colonography (CTC) as a screen for colorectal cancer, a decision that was not unexpected. The agency posted a notification in February that unless a compelling argument arose, it would not cover the procedure.

The proposed decision memo from February indicates that repeated exposure to X-radiation is one of the agency's concerns, but CMS also stated that much of the supporting data featured patients who were "considerably younger than the Medicare aged population," which led to questions about the generalizeability of the supporting data.

Another set of issues for CMS was that because CTC often misses polyps smaller than 6mm in length and surgeons will usually remove these smaller polyps during an operation, little is known about the rate at which such polyps become cancerous.

Durado Brooks, MD, chief of the division of prostate and colon cancer at the American Cancer Society (ACS; Washington) confirmed that concern in an interview with Diagnostics & Imaging Week, but held ground nonetheless, stating that ACS "still see[s] CTC as appropriate technology."

The agency's final decision memo states: "Many questions on the use of CT colonography need to be answered with well designed clinical studies that focus on health outcomes for the Medicare population."

In a May 13 statement, Eamonn Quigley, MD, president of the American College of Gastroenterology (Bethesda, Maryland), stated that the decision " underscores the lack of sufficient evidence on the test's potential." He also noted that a positive finding with CTC usually leads to a full conventional colonoscopy, which is still the gold standard for polyp detection. "Until a radiographic test can meet that standard, gastroenterologists will continue to champion the lifesaving potential of colonoscopy," Quigley said.