United States securities and exchange commission logo September 21, 2021 Duncan Peyton Chief Executive Officer 4D pharma plc 5th Floor, 9 Bond Court Leeds LS1 2JZ United Kingdom Re: 4D pharma plc Registration Statement on Form F-1 Filed September 14, 2021 File No. 333-259501 Dear Mr. Peyton: This is to advise you that we have not reviewed and will not review your registration statement. Please refer to Rules 460 and 461 regarding requests for acceleration. We remind you that the company and its management are responsible for the accuracy and adequacy of their disclosures, notwithstanding any review, comments, action or absence of action by the staff. Please contact Michael Davis at 202-551-4385 or Tim Buchmiller at 202-551-3635 with any questions. Sincerely, Division of Corporation Finance Office of Life Sciences cc: Steven V. Bernard, Esq.