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I have content sitting on a site here - https://www.pfizerpro.co.uk/product/xeljanz/rheumatoid-arthritis - domain authority 25 page authority 18 - the pages went live three months ago and the website was launched 18 months. We now have the option to use a brand new domain www.xeljanz.co.uk Which is the better option to stick with the www.pfizerpro.co.uk as it is a larger multiple topic site that should attract more links or to start a new single topic site which google may view as the better source as it is dedicated to the topic? Thanks