Secondary Endpoint Data for S-033188, a Novel Cap-Dependent Endonuclease Inhibitor for Treatment of Influenza, Support Favorable Primary Endpoint Data Previously Released

OSAKA, Japan–(BUSINESS WIRE)– Shionogi & Co., Ltd. (hereafter “Shionogi”) presented additional clinical data from a Phase 2 proof-of-concept study for S-033188, a cap-dependent endonuclease inhibitor targeting influenza. The primary endpoint data were previously presented at the Options IX for The Control of Influenza conference, held in Chicago on August 24 – 28, 2016. In this study, completed in Japan, a one-day single oral dose of S-033188 demonstrated favorable efficacy on secondary endpoints in otherwise healthy patients with seasonal influenza. These data were reported at the 16th Asia-Pacific Congress of Clinical Microbiology and Infection (hereafter “APCCMI”), held in Melbourne, Australia, November 30 – December 3, 2016.

In this Phase 2 proof-of-concept study, 400 patients were randomized to receive treatment with a single dose (10 mg, 20 mg or 40 mg) of S-033188 or placebo. Secondary endpoints analyzed included time to alleviation of individual systemic and respiratory symptoms and reduction of fever, using the Cox proportional hazards model. Key findings for S-033188 reported at APCCMI include the following results:

  • 40 mg S-033188 was associated with shorter time to alleviation of systemic symptoms compared with placebo, such as feverishness / chills (median 23.0 hours vs. 28.8 hours, p=0.0216), headache (37.9 hours vs. 43.7 hours, p=0.0304), fatigue (31.1 hours vs. 42.7 hours, p=0.0463) and aches and pains (25.4 hours vs 41.9 hours, p=0.0145) and provided more rapid resolution of fever (28.9 hours vs. 45.3 hours, p
  • With regard to respiratory symptoms, nasal congestion was more rapidly resolved with 40 mg S-033188 versus placebo (21.9 hours vs. 42.8 hours, p=0.0081); however, sore throat and cough tended to persist despite rapid viral clearance in patients treated with S-033188.

Based on the primary efficacy (time to alleviation of symptoms), viral load reduction, safety data, and these favorable secondary endpoint data, Shionogi has initiated a global Phase 3 program for otherwise healthy individuals and those at high risk of influenza-associated complications.

About Influenza

Epidemic and pandemic influenza remain a major public health concern, and novel influenza drugs that will offer significant improvement over current therapy are urgently needed. Worldwide, annual influenza epidemics are estimated to result in 3 to 5 million cases of severe illness, and about 250,000 to 500,000 deaths1. In general, those at the highest risk of influenza-associated complications include children under 2 years of age, adults over 65 years of age, pregnant women, and people of any age with certain medical conditions, including chronic heart, lung, metabolic diseases (such as diabetes) and weakened immune systems.

About S-033188

S-033188 is a cap-dependent endonuclease inhibitor with a novel mechanism of action for treatment of influenza. S-033188 is an investigational product being developed for one-time dosing, and has the potential to be more effective than existing marketed anti-influenza products. Development and commercialization are in collaboration with F. Hoffmann-La Roche Ltd.

About Shionogi

Shionogi & Co., Ltd. is a major research-driven pharmaceutical company dedicated to bringing benefits to patients based on its corporate philosophy of “supplying the best possible medicine to protect the health and wellbeing of the patients we serve,” Shionogi’s research and development currently targets two therapeutic areas: infectious diseases, and pain/CNS disorders. For over 50 years, Shionogi has developed and commercialized innovative oral and parenteral anti-infectives. In addition, Shionogi is engaged in new research areas, such as obesity/geriatric metabolic disease and oncology/immunology. Contributing to the health and QOL of patients around the world through development in these therapeutic areas is Shionogi’s primary goal. For more details, please visit For more information on Shionogi Inc., the U.S.–based subsidiary of Shionogi & Co., Ltd., headquartered in Florham Park, NJ, USA, please visit For more information on Shionogi Ltd., the UK-based subsidiary of Shionogi & Co. Ltd., headquartered in London, England, please visit

Forward Looking Statement

This announcement contains forward-looking statements. These statements are based on expectations in light of the information currently available, assumptions that are subject to risks and uncertainties which could cause actual results to differ materially from these statements. Risks and uncertainties include general domestic and international economic conditions such as general industry and market conditions, and changes of interest rate and currency exchange rate. These risks and uncertainties particularly apply with respect to product-related forward-looking statements. Product risks and uncertainties include, but are not limited to, completion and discontinuation of clinical trials; obtaining regulatory approvals; claims and concerns about product safety and efficacy; technological advances; adverse outcome of important litigation; domestic and foreign healthcare reforms and changes of laws and regulations. Also for existing products, there are manufacturing and marketing risks, which include, but are not limited to, inability to build production capacity to meet demand, unavailability of raw materials and entry of competitive products. The company disclaims any intention or obligation to update or revise any forward-looking statements whether as a result of new information, future events or otherwise.


1. WHO website, Influenza (Seasonal), Fact sheet N°211, March 2014

2. Uehara T, Shishido T, et al. S-033188, a Small Molecule Inhibitor of Cap-dependent Endonuclease of Influenza A and B Virus, Leads to Rapid and Profound Viral Load Reduction. Oral presentation at: OPTION IX; August 24-28, 2016; Chicago, IL. LBO-1