User Feedback

Since the L.A.S.S.O. was designed using input from the CF community we wanted them to let us know how well it worked. It was essential to the team that possible future users could use the prototype. Therefore, we took the L.A.S.S.O. back to the our local CF clinic in order to get possible future users to have a go at testing the device.

Michael, a Cystic Fibrosis patient, gives his view on the L.A.S.S.O.;

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Audit

We had an ISO 13485 certified auditor look through our documentation for the L.A.S.S.O. and perform a mock audit to highlight any additional steps we could take to have a product that is as industry-ready as possible. In addition to receiving suggestions about how to improve our documentation (which have been acted upon) we were informed of the following:

In Europe, to obtain a CE mark there are three devices directives:

• Medical Device Directive
• Active Implantable Device Directive
• In Vitro Diagnostics (IVD) Directive

According to the auditor our device, while being “active”, is classed as an IVD and therefore if we were to optimise our device for uptake by a manufacturer we could streamline the process further by satisfying the criteria laid out in the IVD directive. This is being investigated currently.

A product life cycle is split into stages:

• Proof of concept/Feasibility
• Optimisation
• Verification
• Validation
• Launch
• Post Market surveillance
• Withdrawal from the market/end-of-life

We are in the early stages of the above list, with Proof of concept/Feasibility being our main achievement thus far. Optimisation is being carried out currently by testing our device with variable levels of luminescent input. Verification will be carried out by clinical trials with homogenised sputum samples, a portion of which would be analysed by microbiological means (serial dilution and culturing for CFU count and sequencing/PCR for bacterial species identification) to ensure that our device is accurately and reproducibly giving readings of bacterial species and load.

The audit concludes with some general questions on the use of the device. We have answered these below.

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Q. Microbiological concerns – are the specimen receptacles single use? How long can they be stored before the bin needs to be emptied? Will all the samples be from the same patient?

A. The receptacles (plates containing our biological components) will be single use and will be emptied from the bin and disposed of following autoclaving on the day of use. The samples will not all necessarily be from the same patient, this will depend on the number of patients being visited in a day. Neither the team nor medical staff have identified any potential issues with this approach.

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Q. How will consistency be maintained between device batches?

A. During the manufacture of our receptacles and prior to freeze-drying, each inoculum of our biological component will be measured carefully for optical density and a sample will be assayed for activity in the presence of a synthetic signalling molecule. The latter process would be scaled-down to the minimal reaction size required to give a significant result in order to be economically viable.

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Q. What kind of shelf-life/in-use stability are you looking at for this device? How will it be transported and stored?

A. It is difficult to project a shelf–life for this device but based upon the simplicity of the majority of the hardware (plastic casings etc.), if the biennial maintenance checks suggested in our requirements document are carried out for the electronic components, this product will potentially be viable for many years before replacement becomes necessary.

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Q. How can an operator check the test is working – will you provide calibrators or controls?

A. Both a positive and a negative control would be supplied with the device. The negative control would be a plate that was identical to all other receptacles except that it would contain no bacterial culture and thus would also function as a reference measurement. The positive control would be a source of light such as an LED which would give a reliable intensity and wavelength of light. The light source should be of a very low light level so that it would be consistent with the level of light produced by the luciferase. The latter could be built in to future versions of the L.A.S.S.O.