Sinovant Sciences and Nabriva Therapeutics Announce Positive Topline Results from Phase 3 Trial of Lefamulin in Chinese Adults with Community Acquired Bacterial Pneumonia (CABP)

- Lefamulin was shown to be non-inferior to moxifloxacin,with 76.8% of lefamulin-treated patients meeting the efficacy endpoint of Investigator Assessment of Clinical Response (IACR) at Test of Cure (TOC),compared to 71.4% of patients treated with moxifloxacin

- Lefamulin was generally safe and well-tolerated in Chinese adults

- Greater Chinese rights to lefamulin will be held by Sumitomo Pharmaceuticals (Suzhou) Co.,Ltd.,a wholly-owned subsidiary of Sumitomo Dainippon Pharma Co.,Ltd.

HONG KONG and SHANGHAI and SUZHOU,China and DUBLIN,May 26,2021 -- Sinovant Sciences,a Chinese biopharmaceutical company dedicated to conducting innovative biomedical R&D in China,and Nabriva Therapeutics,a biopharmaceutical company engaged in the commercialization and development of innovative anti-infective agents to treat serious infections,today announced positive topline results from Sinovant's Phase 3 bridging study of lefamulin in Chinese adults with community acquired bacterial pneumonia (CABP).

Sinovant's multi-center,randomized,double-blind trial was designed to evaluate the safety and efficacy of intravenous (IV) to oral lefamulin compared to IV/oral moxifloxacin in 125 subjects with CABP. Subjects were randomized 2:1 to lefamulin and moxifloxacin and stratified by prior antibiotic exposure,pneumonia severity index (PSI) risk class,and renal impairment. Study drugs were dosed in double-dummy double-blinded fashion (lefamulin: 150 mg IV every 12 hours,600 mg oral every 12 hours; moxifloxacin: 400 mg IV once daily,400 mg oral once daily).

Lefamulin met the primary endpoint of non-inferiority vs. moxifloxacin for Investigator Assessment of Clinical Response at Test of Cure (IACR-TOC) in the modified intent to treat (mITT) population,with success rates of 76.8% (n = 63/82) for lefamulin and 71.4% (n = 30/42) for moxifloxacin. This finding was consistent across subgroups. On the key secondary endpoint of IACR-TOC in the clinically evaluable (CE) population,success rates were 86.0% (n = 49/57) and 86.2% (n = 25/29) in the lefamulin and moxifloxacin arms,respectively. These results are similar to those observed in the global Phase 3 LEAP 1 and LEAP 2 clinical trials conducted by Nabriva.

Consistent with previously reported clinical trial results,lefamulin was observed to be generally safe and well-tolerated,with an overall rate of treatment-emergent adverse events (TEAEs) comparable to that of moxifloxacin. The vast majority of TEAEs in both treatment arms were mild-to-moderate in severity,with serious adverse events (SAEs) occurring in 4% of lefamulin-treated patients and 10% of moxifloxacin-treated patients. TEAEs leading to discontinuation were uncommon and observed in just 5% of subjects in both treatment arms.

"We are delighted with the results of this trial," said Dr. Rae Yuan,CEO of Sinovant. "These data strongly support the use of lefamulin as an empiric monotherapy for CABP,a disease that affects millions of Chinese patients annually. We look forward to submitting an NDA to China's NMPA as soon as possible."

In addition,Sinovant has entered into an agreement with Sumitomo Pharmaceuticals (Suzhou) Co.,a wholly owned subsidiary of Sumitomo Dainippon Pharma,to acquire development and commercialization rights for lefamulin in Greater China. Under the terms of that agreement,Sinovant will assign its license agreement for lefamulin to Sumitomo Pharmaceuticals (Suzhou),the terms of which are otherwise unchanged. Closing of this transaction is subject to certain conditions and is expected to occur in the second calendar quarter of 2021.

"We are excited to accelerate the availability of lefamulin to Chinese patients upon approval," said Naoki Noguchi,Chairman and CEO of Sumitomo Pharmaceuticals (Suzhou). "These data demonstrate that lefamulin has the potential to be an important new treatment option for patients with CABP. Lefamulin is highly complementary to our existing anti-infective product portfolio in China and we expect it will contribute to our sustained growth in this market."

"We are eager to enter into the next phase of lefamulin's life cycle in China," said Steve Gelone,President and COO of Nabriva. "Sumitomo Pharmaceuticals (Suzhou)'s established commercial infrastructure,particularly in the anti-infectives segment,makes them an ideal partner for Nabriva as we continue to expand global access to lefamulin. We look forward to working with Sumitomo Pharmaceuticals (Suzhou) colleagues to bring this important new medicine to patients."

About Lefamulin

Lefamulin (marketed by Nabriva in the United States as XENLETA®) is a first-in-class,semi-synthetic pleuromutilin antibiotic for systemic administration in humans. It is designed to inhibit the synthesis of bacterial protein,which is required for bacteria to grow. Lefamulin's binding occurs with high affinity,high specificity and at molecular sites that are distinct from other antibiotic classes.

About Sinovant

Sinovant is a Chinese biopharmaceutical company dedicated to conducting innovative biomedical R&D in China. Sinovant's mission is to develop and commercialize new medicines that address the most pressing public health challenges in China while simultaneously advancing Chinese biopharmaceutical research abroad.

About Nabriva Therapeutics plc

Nabriva Therapeuticsis a biopharmaceutical company engaged in the commercialization and development of innovative anti-infective agents to treat serious infections.Nabriva TherapeuticsreceivedU.S. Food and Drug Administrationapproval for XENLETA®(lefamulin injection,lefamulin tablets),the first systemic pleuromutilin antibiotic for community-acquired bacterial pneumonia (CABP).Nabriva Therapeuticsis also developing CONTEPO™ (fosfomycin) for injection,a potential first-in-class epoxide antibiotic for complicated urinary tract infections (cUTI),including acute pyelonephritis. Nabriva entered into an exclusive agreement with subsidiaries of Merck & Co. Inc.,Kenilworth,N.J.,USA to market,sell and distribute SIVEXTRO®(tedizolid phosphate) inthe United Statesand certain of its territories.

About Sumitomo Pharmaceuticals (Suzhou) Co.,Ltd.

Sumitomo Pharmaceuticals (Suzhou) is a subsidiary of Sumitomo Dainippon Pharma Co.,Ltd. and was established in Suzhou,China in 2003. Sumitomo Pharmaceuticals (Suzhou) has 754 employees (as of March 31,2021) and is focusing on the treatment of infectious disease area with mainstay MEPEM® (meropenem hydrate),a carbapenem antibiotic,originally created by Sumitomo Dainippon Pharma. For more information,please visit http://www.dsmpharm.com.cn/.

Forward-Looking Statements

Any statements in this press release about future expectations,plans and prospects for Nabriva Therapeutics,including but not limited to statements about its ability to successfully commercialize XENLETA for the treatment of CABP,including the managed care coverage for XENLETA,the distribution and promotion of SIVEXTRO for the treatment of ABSSSI,the development of CONTEPO for Complicated Urinary Tract Infections (cUTI),the expansion of its commercial sales force,the clinical utility of XENLETA for CABP,SIVEXTRO for ABSSSI and of CONTEPO for cUTI,the impact on gross sales revenue from the recognition of SIVEXTRO sales in its results of operations,the impact of macro events on sales of SIVEXTRO and XENLETA,plans for and timing of the review of regulatory filings for CONTEPO,efforts to bring CONTEPO to market,the market opportunity for and the potential market acceptance of XENLETA for CABP,SIVEXTRO for ABSSSI and CONTEPO for cUTI,the development of XENLETA and CONTEPO for additional indications,the development of additional formulations of XENLETA and CONTEPO,plans for making lefamulin available in the European Union,Canada and China,plans to pursue research and development of other product candidates,plans to pursue business development initiatives,expectations regarding the ability of customers to satisfy demand for XENLETA with their existing inventory,expectations regarding the impact of the interruptions resulting from COVID-19 on its business,the sufficiency of Nabriva Therapeutics' existing cash resources and its expectations regarding anticipated revenues from product sales and how far into the future its existing cash resources will fund its ongoing operations and other statements containing the words "anticipate," "believe," "estimate," "expect," "intend," "may," "plan," "predict," "project," "target," "potential," "likely," "will," "would," "could," "should," "continue," and similar expressions,constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors,including: Nabriva Therapeutics' ability to successfully implement its commercialization plans for XENLETA and SIVEXTRO and whether market demand for XENLETA and SIVEXTRO is consistent with its expectations,Nabriva Therapeutics' ability to build and maintain a sales force for XENLETA and SIVEXTRO,the content and timing of decisions made by the U.S. Food and Drug Administration and other regulatory authorities,the uncertainties inherent in the initiation and conduct of clinical trials,availability and timing of data from clinical trials,whether results of early clinical trials or studies in different disease indications will be indicative of the results of ongoing or future trials,uncertainties associated with regulatory review of clinical trials and applications for marketing approvals,the availability or commercial potential of CONTEPO for the treatment of cUTI,the extent of business interruptions resulting from the infection causing the COVID-19 outbreak or similar public health crises,the ability to retain and hire key personnel,the availability of adequate additional financing on acceptable terms or at all and such other important factors as are set forth in Nabriva Therapeutics' annual and quarterly reports and other filings on file with the U.S. Securities and Exchange Commission. In addition,the forward-looking statements included in this press release represent Nabriva Therapeutics' views as of the date of this press release. Nabriva Therapeutics anticipates that subsequent events and developments will cause its views to change. However,while Nabriva Therapeutics may elect to update these forward-looking statements at some point in the future,it specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing Nabriva Therapeutics' views as of any date subsequent to the date of this press release.

Contact:

Nora Fu

nora.fu@sinovant.com

Nabriva Contact:

Kim Anderson

Nabriva Therapeutics plc

ir@nabriva.com