For a drug / diagnosis technique / medical device to be...

For a drug / diagnosis technique / medical device to be qualified to use safely and, effectively in UK, a license must be issued by Medicines and Healthcare Products Regulatory Agency (MHRA).

In wider Europe, a European Medicines Agency (EMA) licence, is a must.

Similarly, FDA accreditation for USA and TGA for Australia.

So UKCA and CE Mark are not a qualification to recognise the safety and effectiveness of a drug, diagnosis technique or medical device.

References

https://www.gov.uk/government/organisations/medicines-and-healthcare-products-regulatory-agency

https://www.ema.europa.eu/en