Exhibit 15.2

1 May 2017

Securities and Exchange Commission

100 F Street, N.E.

Washington, DC 20549

Commissioners:

We have read the statements made by Motif Bio Plc (copy attached), which we understand will be filed with the Securities and Exchange Commission, pursuant to Item 16F of Form 20-F, as part of the Form 20-F of Motif Bio Plc dated 1 May 2017.  We agree with the statements concerning our Firm in such Form 20-F.

Very truly yours,

/s/ PricewaterhouseCoopers LLP

PricewaterhouseCoopers LLP, The Capitol, 431 Union Street, Aberdeen, AB11 6DA

T: +44 (0) 1224 210 100, F: +44 (0) 1224 253 318, www.pwc.co.uk

PricewaterhouseCoopers LLP is a limited liability partnership registered in England with registered number OC303525.  The registered office of

PricewaterhouseCoopers LLP is 1 Embankment Place, London WC2N 6RH.  PricewaterhouseCoopers LLP is authorised and regulated by the Financial Conduct Authority for designated investment business.