Santhera Provides Update on Timeline for Application of Raxone® in Duchenne Muscular Dystrophy in Europe Liestal, Switzerland, May 19, 2017 – Santhera Pharmaceuticals, a specialty pharmaceutical company focused on the development of innovative treatments for rare mitochondrial and neuromuscular diseases, announces an updated timeline for the ongoing assessment by the Committee for Medicinal Products for Human Use (CHMP) of its extension application for Raxone® (idebenone) in Duchenne muscular dystrophy (DMD). "Santhera is in ongoing, constructive discussions with the CHMP, and we are now expecting to receive a request for supplementary information to further support the clinical relevance of our data. We are working closely with the CHMP to conclude the application process and anticipate an opinion in Q3 2017," said Thomas Meier, PhD, CEO of Santhera. The application was filed as a Type II Variation of the existing marketing authorization and is based on data from Santhera’s phase II (DELPHI) study and the successful pivotal phase III (DELOS) study, the latter in patients not taking concomitant glucocorticoids. This data demonstrated a statistically significant and clinically relevant benefit of Raxone in preserving respiratory function compared to placebo. This result is further substantiated by a natural history study, which shows that the benefits observed in the group treated with Raxone would not have been expected from the natural course of the disease. The intended indication for Raxone is to slow the loss of respiratory function in patients with DMD who are currently not taking glucocorticoids. The indication would include patients who were previously treated with glucocorticoids or in whom glucocorticoid treatment is not desired, not tolerated, or is contraindicated. About Duchenne Muscular Dystrophy DMD is one of the most common and devastating types of muscle degeneration and leads to progressive muscle weakness starting at an early age. DMD is a genetic, degenerative disease that occurs almost exclusively in males with an incidence of up to 1 in 3,500 live male births worldwide. About Idebenone in Duchenne Muscular Dystrophy DMD is characterized by a loss of the protein dystrophin, leading to cell damage, impaired calcium homeostasis, elevated oxidative stress and reduced energy production in muscle cells. This results in progressive muscle weakness, muscle wasting, early morbidity and mortality due to respiratory failure. Idebenone is a synthetic short-chain benzoquinone and a cofactor for the enzyme NAD(P)H:quinone oxidoreductase (NQO1) capable of stimulating mitochondrial electron transport, reducing and scavenging reactive oxygen species (ROS) and supplementing cellular energy levels. DELOS was a phase III, double-blind, placebo-controlled 52-week study which randomized 64 patients, not taking concomitant steroids, to receive either idebenone (900 mg/day) or matching placebo. The study met its primary endpoint, the change from baseline in Peak Expiratory Flow (PEF), which demonstrated that idebenone can slow the loss of respiratory function. Idebenone was well tolerated in the DELOS study, with overall incidence of adverse events being similar to placebo. The statistically significant and clinically relevant outcomes of the phase III DELOS study were published: Buyse et al., The Lancet 2015, 385:1748-1757; McDonald et al., Neuromuscular Disorders 2016, 26:473-480 and Buyse et al., Pediatric Pulmonology 2017, 52:580-515. The European Medicines Agency’s CHMP and the Swiss regulatory authority Swissmedic are currently assessing a Marketing Authorization Application for idebenone under the name Raxone in patients with DMD with respiratory function decline who are not taking glucocorticoids. About Santhera Santhera Pharmaceuticals (SIX: SANN) is a Swiss specialty pharmaceutical company focused on the development and commercialization of innovative pharmaceutical products for the treatment of orphan mitochondrial and neuromuscular diseases. Santhera's lead product Raxone® (idebenone) is authorized in the European Union, Norway, Iceland and Liechtenstein for the treatment of Leber's hereditary optic neuropathy (LHON). For Duchenne muscular dystrophy (DMD), Santhera has filed a Marketing Authorization Application in the European Union and Switzerland for DMD patients with respiratory function decline who are not taking glucocorticoids. In collaboration with the U.S. National Institute of Neurological Disorders and Stroke (NINDS) Santhera is developing Raxone® in a third indication, primary progressive multiple sclerosis (PPMS), and omigapil for congenital muscular dystrophy (CMD), all areas of high unmet medical need. For further information, please visit the Company's website www.santhera.com. Raxone® is a trademark of Santhera Pharmaceuticals. For further information, contact: Thomas Meier, PhD, Chief Executive Officer Christoph Rentsch, Chief Financial Officer Phone +41 61 906 89 64 Phone +41 61 906 89 65 [email protected] [email protected] Sue Schneidhorst, Head Group Communications Phone +41 61 906 89 26 [email protected] US investor contact Hans Vitzthum, LifeSci Advisors, LLC Phone +1 212 915 2568 [email protected] Disclaimer / Forward-looking statements This communication does not constitute an offer or invitation to subscribe for or purchase any securities of Santhera Pharmaceuticals Holding AG. This publication may contain certain forward-looking statements concerning the Company and its business. Such statements involve certain risks, uncertainties and other factors which could cause the actual results, financial condition, performance or achievements of the Company to be materially different from those expressed or implied by such statements. Readers should therefore not place undue reliance on these statements, particularly not in connection with any contract or investment decision. The Company disclaims any obligation to update these forward-looking statements.