ACACIA PHARMA PROVIDES FURTHER UPDATE ON FDA REGULATORY REVIEW OF BARHEMSYS™

This announcement contains inside information for the purposes of Article 7 of the Market Abuse Regulation (EU) No 596/2014.

Cambridge, UK and Indianapolis, US – 15 October 2018: Acacia Pharma Group plc (“Acacia Pharma” or “the Company”) provides an update following receipt of a Complete Response Letter (CRL) from the US Food and Drug Administration (FDA) in respect of its New Drug Application (NDA) for BARHEMSYS™ (amisulpride injection) on 5 October 2018.

“Our discussions with FDA and our contract manufacturer over the past week have been productive and provided clarification on the steps needed to enable our NDA for BARHEMSYS to be approved. Our contract manufacturer is fully committed to working with Acacia Pharma to institute a corrective and preventative action plan that will rectify the deficiency identified as quickly as possible. We continue to plan for a launch in the first half of 2019,” said Dr Julian Gilbert, CEO of Acacia Pharma.

On 8 October, the Company announced that the CRL had identified deficiencies relating to the pre-approval inspection of the contract facility employed to manufacture amisulpride, the active pharmaceutical ingredient in BARHEMSYS. No defects were noted in the purity or stability of the active ingredient, or in the manufacturing process or quality of the finished product. In addition, no concerns were raised by FDA on any of the clinical or non-clinical data in the application and no further studies or data analyses will be required for approval.

During the first week of October Acacia Pharma was informed by the contract manufacturer that it had received a post-inspection notification from FDA stating that its facility met an acceptable standard of compliance with regard to current good manufacturing practice (CGMP). Late last week the contract manufacturer shared with the Company a copy of an “Untitled Letter”* that it had subsequently received from FDA giving details of one specific deficiency which requires correction before the NDA for BARHEMSYS may be approved.

The Company is working closely with the contract manufacturer to prepare a robust Corrective and Preventive Action (CAPA) plan to address the outstanding deficiency. The Company has engaged a former senior FDA official with regulatory, compliance and enforcement expertise to provide additional oversight and guidance on the plan.

The CAPA plan is expected to be completed within one month to enable Acacia Pharma to resubmit its NDA for BARHEMSYS. Within 30 days of resubmission the FDA will classify it as either Class 1 (review completed within two months of receipt) or Class 2 (review completed within six months of receipt). Further updates in relation to these events will be provided in due course.

*Footnote: “Untitled letters” are used by FDA to request correction of deficiencies that may not meet the threshold of regulatory significance for a warning letter. Unlike a warning letter, an Untitled Letter does not include a statement warning that failure to promptly correct the deficiency may result in enforcement action.

The Acacia Pharma management team will host a conference call today, Monday 15 October 2018, at 10.00am CEST. Please join the event conference 5-10 minutes prior to the start using the confirmation code and any of the phone numbers provided below.

Contacts

Acacia Pharma Group plc

Julian Gilbert, CEO

Christine Soden, CFO

+44 1223 919760

IR@acaciapharma.com

Citigate Dewe Rogerson (Financial PR)

Mark Swallow, Shabnam Bashir, David Dible

+44 20 7638 9571

acaciapharma@citigatedewerogerson.com

About Acacia Pharma

Acacia Pharma is a hospital pharmaceutical company focused on the development and commercialisation of new nausea & vomiting treatments for surgical and cancer patients. The Group has identified important and commercially attractive unmet needs in nausea & vomiting and has discovered two product candidates based on the same active ingredient, amisulpride, to meet those needs.

The Group’s lead project, BARHEMSYS™ for post-operative nausea & vomiting (PONV), has generated positive results in four Phase 3 clinical studies. Its sister project, APD403 for chemotherapy induced nausea & vomiting (CINV), has successfully completed one proof-of-concept and one Phase 2 dose-ranging study in patients receiving highly emetogenic chemotherapy.

Acacia Pharma is based in Cambridge, UK and its US operations are centred in Indianapolis, IN. The Company is listed on the Euronext Brussels exchange under the under ISIN code GB00BYWF9Y76 and ticker symbol ACPH. www.acaciapharma.com

Forward looking statement

This announcement includes forward-looking statements, which are based on current expectations and projections about future events. These statements may include, without limitation, any statements preceded by, followed by or including words such as “believe”, “expect”, “intend”, “may”, “plan”, “will”, “should”, “could” and other words and terms of similar meaning or the negative thereof. Forward-looking statements may and often do differ materially from actual results. These forward-looking statements are subject to risks, uncertainties and assumptions about the Company and its subsidiaries and investments, including, among other things, the development of its business, trends in its operating industry, and future capital expenditures and acquisitions. By their nature, forward-looking statements involve risk and uncertainty because they relate to future events and circumstances. Any forward-looking statements reflect the Company’s current view with respect to future events and are subject to risks relating to future events and other risks, uncertainties and assumptions relating to the Group’s business, results of operations, financial position, prospectus, growth or strategies and the industry in which it operates. Save as required by law or applicable regulation, the Company and its affiliates expressly disclaim any obligation or undertaking to update, review or revise any forward-looking statement contained in this announcement whether as a result of new information, future developments or otherwise. Forward-looking statements speak only as of the date they are made.