(a) Identification. A device to detect bacterial protease activity in chronic wound fluid is a lateral flow prescription in vitro diagnostic device that may include a sterile swab. The device is intended for use in patients as an aid in assessing the risk for non-healing of chronic venous, diabetic foot, and pressure ulcers associated with wounds where there are no signs of wound infection and where patients are asymptomatic for clinical signs of infection.

(b) Classification. Class II (special controls). The special controls for this device are:

(1) Any swab used to collect a patient specimen must be FDA-cleared, -approved, or -classified as 510(k) exempt (standalone or as part of a test system) for the collection of wound fluid specimens; alternatively, the sample collection device must be cleared in a premarket submission as a part of this device.

(2) The labeling required under § 809.10(b) of this chapter must include:

(i) An intended use that includes the following statements:

(A) A statement that the device detects and measures bacterial proteases from a swab saturated with wound fluid.

(B) A statement that the device provides a qualitative output to aid the user in assessing the risk for non-healing of wounds (e.g., chronic venous, diabetic foot and pressure ulcers).

(C) A description of the clinical indications for test use.

(D) The specific population(s) for which the device is intended.

(E) A description of the recommended training (e.g., knowledge and experience) for safe and effective use of the device and to minimize the risks of incorrect results and misinterpretation.

(ii) A detailed description of the performance characteristics of the device from the analytical and clinical studies required under paragraphs (b)(3)(ii) and (iii) of this section.

(iii) A detailed explanation of the interpretation of results.

(iv) A warning statement describing situations where the device has not been validated or may not perform as identified in the labeling (e.g., not for use with wounds which are ≥6 months of age and ≥1 cm 2 in size).

(v) The following limiting statements:

(A) That the device is not intended to provide a risk assessment of chronic wound infection status or aid in the diagnosis of infection in chronic wounds, nor is the device intended for monitoring the effectiveness of anti-infective therapy.

(B) That a negative result does not exclude the presence of bacterial proteases. Therefore, the results should be used in conjunction with clinical findings to make an accurate assessment of risk of nonhealing. The test result should be interpreted in conjunction with other risk factors, along with clinical and laboratory data available to the clinician.

(C) That the device has been validated using wound fluid samples only. Other sample types (e.g., whole blood from venous or capillary draws, other body fluids) have not been evaluated.

(D) That skin flora may secrete bacterial proteases therefore, swab contact with intact skin should be avoided as this may yield false positive results.

(vi) Labeling must include a brief reference sheet for healthcare professionals that includes the intended use, summary of clinical performance, results from analytical testing on normal skin and human proteases, and warning and limiting statements.

(3) Design verification and validation must include the following:

(i) A detailed device description (e.g., all device parts, control elements incorporated into the test procedure, reagents required but not provided, and the principle of device operation and test methodology).

(ii) Detailed documentation and results from analytical studies, including the limit of detection, inclusivity, cross-reactivity, microbial interference, analytical sensitivity for normal skin flora and human proteases, interfering substances, specimen stability, within-lab precision, and reproducibility.

(iii) Detailed documentation and results from a clinical study that includes prospective (sequentially collected) samples for the intended specimen type that are representative of the intended use population(s). The clinical study must compare the device performance to results obtained from a reference or comparator method that FDA has determined is appropriate.