• The 21 serotypes covered by V116 are responsible for approximately 83% of invasive pneumococcal disease in individuals 65 years of age and older, according to CDC data from 2018-2021
• Results from Phase 3 trial, STRIDE-3, to be presented at World Vaccine Congress West Coast

RAHWAY, N.J. / Nov 28, 2023 / Business Wire / Merck (NYSE: MRK), known as MSD outside of the United States and Canada, today announced results from STRIDE-3, a Phase 3 trial evaluating V116, the company’s investigational 21-valent pneumococcal conjugate vaccine specifically designed to protect adults. The trial evaluated the immunogenicity, tolerability and safety of V116 compared to PCV20 (pneumococcal 20-valent conjugate vaccine) in adults who had not previously received a pneumococcal vaccine.

Results from the study’s primary objectives include:

• In adults 50 years of age and older (Cohort 1), V116 elicited non-inferior immune responses compared to PCV20 for all 10 serotypes common to both vaccines as measured by serotype-specific opsonophagocytic activity (OPA) geometric mean titers (GMTs) at Day 30.
• Immune responses elicited by V116 were superior for 10 of 11 serotypes included in V116 but not in PCV20 as measured by OPA GMTs at Day 30 and the proportions of patients with a greater than or equal to four-fold increase in OPA from Day 1 to Day 30.
• In adults 18 to 49 years of age (Cohort 2), V116 elicited non-inferior immune responses (immunobridged) compared to adults 50 to 64 years of age, as assessed by serotype-specific OPA GMTs 30 days post-vaccination.
• Across both cohorts, V116 had a safety profile comparable to PCV20.

Detailed findings will be presented today at World Vaccine Congress West Coast at 4:50 p.m. EST. The company announced topline results of the STRIDE-3 trial earlier this year.

According to CDC data from 2018-2021, the serotypes covered by V116 are responsible for approximately 83% of invasive pneumococcal disease in individuals 65 years of age and older. V116 includes eight unique serotypes not covered by currently licensed pneumococcal vaccines, which were responsible for approximately 30% of invasive pneumococcal disease in individuals 65 years of age and older, based on the same CDC data. If approved, V116 would be the first pneumococcal conjugate vaccine specifically designed for adults.

“These results provide strong evidence to support the immunogenicity of V116 compared to the standard of care in the prevention of invasive pneumococcal disease and pneumococcal pneumonia in adults,” said Dr. Eliav Barr, senior vice president, head of global clinical development and chief medical officer, Merck Research Laboratories. “We are excited by the potential of V116 to impact public health through primary prevention through the use of a population-specific strategy that targets the serotypes responsible for the majority of invasive pneumococcal disease in adults.”

“Invasive forms of pneumococcal disease can cause serious and sometimes life-threatening complications, such as pneumococcal pneumonia, pneumococcal meningitis and bacteremia, especially for older or immunocompromised adults,” said Dr. Sady Alpizar, Clinical Research Trials of Florida, Inc., and a principal investigator of the study. “These encouraging results demonstrate that V116 has the potential to help prevent invasive pneumococcal disease among vulnerable populations.”

The V116 Phase 3 clinical development program is composed of eight trials (n=8,830) investigating the safety, tolerability and immunogenicity of V116 in various adult populations. These include adults with and without chronic medical conditions associated with an increased risk of pneumococcal disease, as well as individuals who previously received a pneumococcal vaccine. An overview of the late-stage development program is available here.

Merck is sharing data from STRIDE-3 with global regulatory authorities.

Study Design and Additional Data from STRIDE-3

STRIDE-3 (NCT05425732) is a Phase 3, randomized, double-blind, active comparator-controlled study evaluating the safety, tolerability, and immunogenicity of V116 compared to PCV20 in adults 18 years of age and older who had not previously received a pneumococcal conjugate vaccine (n=2,663). Participants were randomized to receive a single dose of either V116 or PCV20.

Primary endpoints across both cohorts included safety, serotype-specific OPA GMTs 30 days post-vaccination and percentage of participants with greater than or equal to four-fold rise from baseline in serotype-specific OPAs. Cohort 1 enrolled participants 50 years of age and older (n=2,362) who were randomized 1:1 to receive a single dose of either V116 or the comparator, PCV20. Key findings from primary endpoints include:

• V116 was non-inferior to PCV20 for the 10 serotypes common to both vaccines (3, 6A, 7F, 8, 10A, 11A, 12F, 19A, 22F, 33F), as assessed by serotype-specific OPA GMTs 30 days post-vaccination.
• V116 was superior to PCV20 for 10 of 11 serotypes included in V116 but not in PCV20 (9N, 15A, 16F, 17, 20A, 23A, 23B, 24F, 31, 35B), as assessed by serotype-specific OPA GMTs 30 days post-vaccination and the proportions of patients with a greater than or equal to four-fold increase in OPA from Day 1 to Day 30.
  • Immune responses were observed for serotype 15C in participants receiving V116, but these did not meet criteria for statistical superiority.

Cohort 2 enrolled participants 18-49 years of age (n=301) who were randomized 2:1 to receive a single dose of either V116 or comparator, PCV20. Results from primary endpoints showed immune responses elicited by V116 in participants 18-49 years of age were non-inferior (immunobridged) compared to participants 50-64 years of age for all 21 serotypes, as assessed by serotype-specific OPA GMTs 30 days post-vaccination.

Across both cohorts, V116 had a safety profile comparable to PCV20. Participants administered V116 and PCV20 who reported at least 1 adverse event (AE) were 61.7% and 67.2%, respectively. There were no vaccine-related serious AEs or vaccine-related deaths in the study.

About V116

V116 is an investigational, 21-valent pneumococcal conjugate vaccine in Phase 3 development for the prevention of invasive pneumococcal disease and pneumococcal pneumonia in the adult population. V116 is specifically designed to address Streptococcus pneumoniae serotypes predominantly responsible for adult pneumococcal disease, including eight unique serotypes, 15A, 15C, 16F, 23A, 23B, 24F, 31 and 35B, which account for approximately 30% of adult disease, according to CDC data from 2018-2021. The serotypes covered by V116 are responsible for approximately 83% of invasive pneumococcal disease in individuals 65 years of age and older, based on the same CDC data.

The V116 Phase 3 program includes multiple studies, including STRIDE-3 (NCT05425732), STRIDE-4 (NCT05464420), STRIDE-5 (NCT05526716), STRIDE-6 (NCT05420961), STRIDE-7 (NCT05393037), STRIDE-8 (NCT05696080), STRIDE-9 (NCT05633992) and STRIDE-10 (NCT05569954).

About Pneumococcal Disease

Pneumococcal disease is an infection caused by bacteria called Streptococcus pneumoniae. There are more than 100 different types (referred to as serotypes) of pneumococcal bacteria, which can affect adults differently than children. Certain serotypes threaten to put more people at risk for invasive pneumococcal illnesses, such as bacteremia (infection in the bloodstream); bacteremic pneumonia (pneumonia with bacteremia); and meningitis (infection of the coverings of the brain and spinal cord), as well as non-invasive pneumonia (when pneumococcal disease is confined to the lungs).

While healthy adults can suffer from pneumococcal disease, patient populations particularly vulnerable to infection include older adults and those with certain chronic or immunocompromising health conditions, such as heart disease, lung disease and liver disease. Mortality from invasive pneumococcal disease is highest among adults 50 years of age and older.

Merck’s Commitment to Pneumococcal Disease Protection

Merck has been at the forefront of pneumococcal disease prevention through vaccination for more than four decades and remains committed to helping to protect people of all ages from this disease. Merck’s ongoing pneumococcal vaccine development program is designed to provide options to address the specific needs of different populations, including infants and children, healthy adults and at-risk subgroups. This approach recognizes that disease burden in pediatric and adult populations is often driven by different bacterial strains, or serotypes, and aims to address unmet needs by offering vaccine options that target serotypes posing the greatest global risk to each population. To learn more about Merck’s pipeline, visit https://www.merck.com.

About Merck

At Merck, known as MSD outside of the United States and Canada, we are unified around our purpose: We use the power of leading-edge science to save and improve lives around the world. For more than 130 years, we have brought hope to humanity through the development of important medicines and vaccines. We aspire to be the premier research-intensive biopharmaceutical company in the world – and today, we are at the forefront of research to deliver innovative health solutions that advance the prevention and treatment of diseases in people and animals. We foster a diverse and inclusive global workforce and operate responsibly every day to enable a safe, sustainable and healthy future for all people and communities. For more information, visit www.merck.com and connect with us on X (formerly Twitter), Facebook, Instagram, YouTube and LinkedIn.

Forward-Looking Statement of Merck & Co., Inc., Rahway, N.J., USA

This news release of Merck & Co., Inc., Rahway, N.J., USA (the “company”) includes “forward-looking statements” within the meaning of the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. These statements are based upon the current beliefs and expectations of the company’s management and are subject to significant risks and uncertainties. There can be no guarantees with respect to pipeline candidates that the candidates will receive the necessary regulatory approvals or that they will prove to be commercially successful. If underlying assumptions prove inaccurate or risks or uncertainties materialize, actual results may differ materially from those set forth in the forward-looking statements.

Risks and uncertainties include but are not limited to, general industry conditions and competition; general economic factors, including interest rate and currency exchange rate fluctuations; the impact of the global outbreak of novel coronavirus disease (COVID-19); the impact of pharmaceutical industry regulation and health care legislation in the United States and internationally; global trends toward health care cost containment; technological advances, new products and patents attained by competitors; challenges inherent in new product development, including obtaining regulatory approval; the company’s ability to accurately predict future market conditions; manufacturing difficulties or delays; financial instability of international economies and sovereign risk; dependence on the effectiveness of the company’s patents and other protections for innovative products; and the exposure to litigation, including patent litigation, and/or regulatory actions.

The company undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. Additional factors that could cause results to differ materially from those described in the forward-looking statements can be found in the company’s Annual Report on Form 10-K for the year ended December 31, 2022 and the company’s other filings with the Securities and Exchange Commission (SEC) available at the SEC’s Internet site (www.sec.gov).