US FDA approval and EU CE-marking for medical devices cover most of the world. A manufacturer will need both. China, S.Korea and Japan are likely to demand a FDA-type application be re-submitted. In Russia it appears to depend on the custom official on the day (my experience is a decade old).
The GHTF are working on harmonising the various regimes, for global mutual recognition. But it is a slow process, often stalled by protectionisms. The FDA in particular appears to have a hard time accepting anything non-US medical.
USA:
US OTC Bill deregulates the prescription of medical
hearing devices. The devices must still be approved by the FDA for medical purposes. The OTC Bill includes provision for establishing novel OTC products and care system categories. The de novo is one route to obtaining approval for the unpresedented. Once a couple of de novo approvals have satisfied the FDA confidence in a new medical concept, others can claim equivalence and follow by using a much slimmed down 510k application procedure. It is however difficult to see how the FDA can declare such confidence until after OTC has proven itself in practice.
On the other hand, Boost and its EarID function are possibly close enough in concept to a traditional hearing aid and audiometry, for which 510k classes exist already. This could simplify the regulatory process, but I am only speculating here.
It could be reasonable to hold out and wait and see if a less time-cost demanding option will become availble, while OTC hasn't yet started. This would importantly also overcome the dilemma mentioned previously.
The FDA have a regime for how they want to see clinical studies conducted and monitored in accordance with recognised standards. From experience, they can be perculiar about accepting foreign studies. Oldenburg are highly respected, but I don't know how this study was conducted. I have no opinion whether the FDA would accept the Oldenburg study.
Europe:
Regulatory requirements in Europe are highly similar to the US, but, BIG BUT, the approval regime differs significantly. For the EU, the manufacturer self-certifies that the medical hearing device meets the regulatory requirements, before himself releasing it into the market with a CE-mark. The manufacturer follows a laid down conformity assessment procedure and registers with a quality assurance body that audits that the manufacturers process is compliant. The manufacturer self can effectively decide whether the Oldenburg study is appropriate and sufficient in evidencing clinical performance, supported by a review by a third party auditor of course.
The dispensing process is regulated differently in various European countries. There is no harmonised approach, but national authorities cannot hinder free trade across the borders. They can only request the EU to introduce a common regulation, if they don't like what is legally coming in over its border from another EU or EEA state.
UK:
Is in Europe, still. A medical hearing aid with a self-fitting feature is not a prescription device in the UK and can be sold DTC for self-service. Only the commercial healthcare dispensing process is regulated. The UK effectively has an OTC equivalent channel already. Medical hearing aids are already being legally sold on Amazon and eBay in the UK.
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