Mainstay Medical International : 2016 H1 Results Notice

Press Release

Dublin - Ireland, 12 September 2016 - Mainstay Medical International plc ("Mainstay" or the "Company", Euronext Paris: MSTY.PA and ESM of the Irish Stock Exchange: MSTY.IE), a medical device company focused on bringing to market ReActiv8®, an implantable neurostimulation system to treat disabling Chronic Low Back Pain ("CLBP"), will release its 2016 Half Year results on Thursday, 22 September 2016 at 7:00am Dublin time.

Peter Crosby, Chief Executive Officer and Hugh Kavanagh, Chief Financial Officer, will host a live conference call for analysts and investors at 3:00pm Dublin time (4:00pm Paris, 10:00am New York) on the day. The call will be conducted in English and a replay will be available for 30 days.

Dial-ins for the call are outlined below:

The results press release will be available on the "Investors" section of the Mainstay Medical website at: http://www.mainstay-medical.com/investors

During the conference call, there will be an opportunity to ask questions. Instructions for this will be provided at the start of the call. Questions for the conference call are welcomed in advance via e-mail to investor-relations@mainstay-medical.com

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Press Release

Mainstay is a medical device company focused on bringing to market an innovative implantable neurostimulation system, ReActiv8®, for people with disabling Chronic Low Back Pain (CLBP). The Company is headquartered in Dublin, Ireland. It has subsidiaries operating in Ireland, the United States, Australia and Germany, and its ordinary shares are admitted to trading on Euronext Paris (MSTY.PA) and the ESM of the Irish Stock Exchange (MSTY.IE).

CAUTION - in the United States, ReActiv8 is limited by federal law to investigational use only.

One of the recognised root causes of CLBP is impaired control by the nervous system of the muscles that dynamically stabilise the spine in the low back, and an unstable spine can lead to back pain. ReActiv8 is designed to electrically stimulate the nerves responsible for contracting these muscles and thereby help to restore muscle control and improve dynamic spine stability, allowing the body to recover from CLBP.

People with CLBP usually have a greatly reduced quality of life and score significantly higher on scales for pain, disability, depression, anxiety and sleep disorders. Their pain and disability can persist despite the best available medical treatments, and only a small percentage of cases result from an identified pathological condition or anatomical defect that may be correctable with spine surgery. Their ability to work or be productive is seriously affected by the condition and the resulting days lost from work, disability benefits and health resource utilisation put a significant burden on individuals, families, communities, industry and governments.

Further information can be found at www.mainstay-medical.com

Chris Gardner, Mary-Jane Elliott, Jessica Hodgson, Hendrik Thys Tel: +44 203 709 5700 / +44 7921 697 654

Email: mainstaymedical@consilium-comms.com

Jonathan Neilan

Tel: +353 1 663 3686

Email: jonathan.neilan@fticonsulting.com

Tel: + 1 (212) 915-2578

Email: britchie@lifesciadvisors.com

Fergal Meegan or Barry Murphy Tel: +353 1 679 6363

Email: fergal.meegan@davy.ie or barry.murphy2@davy.ie