FDA Accepts Shionogi’s Ensitrelvir NDA for Review as the First Oral Therapy for the Prevention of COVID-19 Following Exposure

Shionogi & Co., Ltd. (Head Office: Osaka, Japan; Chief Executive Officer: Isao Teshirogi, Ph.D.; hereafter “Shionogi”) announced the U.S. Food and Drug Administration (FDA) has accepted for review a New Drug Application (NDA) from Shionogi Inc., a New Jersey-based subsidiary of Shionogi, for ensitrelvir (Generic name: ensitrelvir fumaric acid, Code No.: S-217622), an investigational oral antiviral for the prevention of COVID-19 following exposure to an infected individual. The FDA has set an action date of June 16, 2026 under the Prescription Drug User Fee Act (PDUFA).

The NDA is supported by results from the global, double-blind, randomized, placebo-controlled Phase 3 study, SCORPIO-PEP, which studied ensitrelvir as post-exposure prophylaxis (PEP). If approved, ensitrelvir would be the first and only oral therapy for the prevention of COVID-19 following exposure to an infected individual.1,2

SARS-CoV-2 remains highly transmissible and up to half of people living with an infected individual may develop COVID-19.3,4 The virus is constantly evolving, with novel symptoms reported.5,6 COVID-19 continues to impact daily life and may lead to absences from school and work, may cause long COVID, and in some cases, may progress to severe disease.7-12 Even patients with mild COVID-19 may experience worsening of preexisting chronic conditions.13-17

Following exposure to COVID-19, the best way to avoid its potentially serious and long-term complications is to stop viral replication, which prevents the development of the disease.1,2 There are currently no approved antiviral therapies proven to prevent COVID-19 following exposure.1,2,18 COVID-19 vaccines are received before exposure, and they do not stop viral replication.19,20 Other COVID-19 antivirals are taken following exposure and diagnosis, after viral replication has occurred and disease is already established.21

“Shionogi has a long history of innovation in infectious disease treatment and prevention. Our dedication to this field has led to significant breakthroughs in the development of novel antimicrobials and antivirals for HIV/AIDS, influenza and COVID-19. If approved, ensitrelvir will be the first and only oral therapy to help protect people in the U.S. from COVID-19 following exposure," said Nathan McCutcheon, MBA, President and CEO, Shionogi Inc.

About ensitrelvir

Ensitrelvir is a SARS-CoV-2 main protease inhibitor created through joint research between Hokkaido University and Shionogi. SARS-CoV-2 has an enzyme called the main protease (3-CL), which is essential for the replication of the virus. Ensitrelvir suppresses the replication of SARS-CoV-2 by selectively inhibiting the main protease.

Ensitrelvir, known as Xocova® in countries where it is approved, received emergency regulatory approval in Japan in November 2022 and full approval in March 2024 for the treatment of COVID-19 based on results from SCORPIO-SR, a Phase 3 study conducted in Asia, during the Omicron-dominant phase of the pandemic.

In SCORPIO-SR, ensitrelvir showed both clinical symptomatic efficacy (symptom resolution sustained for at least 24 hours) for five typical Omicron-related symptoms (primary endpoint) and antiviral efficacy (key secondary endpoint) in a predominantly vaccinated population of patients with mild-to-moderate SARS-CoV-2 infection, regardless of risk factors. Most adverse events were mild in severity and no deaths were seen in the study. Among the most common treatment-related adverse events were temporary decreases in high-density lipoprotein and increased blood triglycerides, as observed in previous studies. Results from this study were published in JAMA Network Open.

In 2025, Shionogi submitted two new drug applications in Japan for post-exposure prophylaxis of COVID-19 and for COVID-19 treatment in pediatric patients aged six to under 12 years. The pediatric submission is based on a multicenter, randomized, double-blind, placebo-controlled trial of ensitrelvir in mild-to-moderate COVID-19 patients aged 6 to 12 years in Japan. The study confirmed safety and tolerability and found the pharmacokinetics of ensitrelvir in this age group to be similar to that in adults.

Ensitrelvir became available in Singapore for the treatment of COVID-19 via a Special Access Route application in 2023, and it is currently under regulatory review in Taiwan for the treatment of COVID-19. Ensitrelvir is also under regulatory review with the European Medicines Agency for COVID-19 post-exposure prophylaxis and treatment.22

Ensitrelvir is an investigational drug outside of Japan and Singapore. In addition, the brand name Xocova® has not been approved for use outside of Japan and Singapore and pertains only to the approved drug in Japan and Singapore.

FDA Accepts Shionogi’s Ensitrelvir NDA for Review as the First Oral Therapy for the Prevention of COVID-19 Following Exposure

Achieve Life Sciences Announces FDA Acceptance of Cytisinicline New Drug Application for Treatment of Nicotine Dependence for Smoking Cessation

Achieve Life Sciences, Inc. (Nasdaq: ACHV), a late-stage specialty pharmaceutical company focused on the global development and commercialization of cytisinicline for treatment of nicotine dependence, today announced that the U.S. Food and Drug Administration (FDA) has accepted the cytisinicline New Drug Application (NDA) for a new treatment for smoking cessation in adults. The FDA has assigned a Prescription Drug User Fee Act (PDUFA) targeted action date of June 20, 2026.

“The FDA’s acceptance of our NDA validates the totality of our product development program,” said Dr. Cindy Jacobs, President and Chief Medical Officer of Achieve Life Sciences. “Our application is supported by a decade of rigorous research and comprehensive data from thousands of participants. We've built compelling scientific and clinical results as a foundation that, if approved, positions cytisinicline to potentially address a significant medical need. We’re eager to engage constructively with the FDA as we progress through the NDA review process.”

The company’s NDA details a comprehensive clinical development program, with more than 2,000 clinical trial participants contributing to the body of evidence. The ORCA-2 and ORCA-3 Phase 3 trials showed cytisinicline administered for either 6 or 12 weeks, alongside standard behavioral support, demonstrated significantly greater smoking abstinence rates by the end of treatment and in long-term abstinence through week 24 as compared to placebo. In addition, safety data will include over 400 participants who have received at least six months of cumulative cytisinicline exposure and over 200 participants receiving at least 1 year of cumulative cytisinicline exposure, with no new safety concerns as reported by the Data Safety Monitoring Committee.

“Smoking is the leading cause of preventable death and disease, claiming the lives of nearly half a million Americans each year, and costing the American economy more than an estimated $600 billion a year,” said Rick Stewart, Chief Executive Officer of Achieve Life Sciences. “The FDA's acceptance of our NDA filing underscores nicotine dependence as an important public health need that demands action. We're energized by this milestone and remain laser-focused on our mission, working toward commercial readiness for the second half of 2026, pending FDA approval. Each year, an estimated 15 million Americans attempt to quit smoking, and we're committed to providing those who are ready to quit a new tool so they can break free from nicotine dependence.”

https://en.wikipedia.org/wiki/Cytisine

Achieve Life Sciences Announces FDA Acceptance of Cytisinicline New Drug Application for Treatment of Nicotine Dependence for Smoking Cessation