FDA Approves Pneumococcal 15-Valent Conjugate Vaccine for US Adults

The prophylaxis showed non-inferiority across shared serotypes with an available 13-valent vaccine in its indication-supporting data.

The US Food and Drug Administration (FDA) has approved pneumococcal 15-valent conjugate vaccine (VAXNEUVANCE) for the active-immunization prevention of invasive disease caused by Streptococcus pneumoniae (IPD) among adults ≥18 years old.

The indication, granted to Merck, includes prevention of disease caused by serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 22F, 23F and 33F. The Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) are anticipated to provide recommendations regarding the new vaccine in October.

The approval for the 15-valent vaccine was based on findings from 7 randomized, double-blind, clinical trials showing its non-inferior immune response to marketed 13-valent pneumococcal conjugate vaccine (PCV13) for the 2 vaccine’s shared 13 serotypes, per opsonophagocytic activity (OPA) Geometric Mean Titers (GMTs).

Investigators from the clinical trials additionally reported superior immune response with the 15-valent vaccine versus PCV13 for shared serotype 3, plus 22F and 33F. The pivotal phase 3 PNEU-AGE trial showed 15-valent vaccine’s superiority to PCV13 based on statistically significantly greater OPA GMT ratios for serotypes 22F (GMT ratio, 32.52; 95% CI, 25.87 – 40.88) and 33F (7.19; 95% CI, 6.13 – 8.43).

The OPA GMT ratio for serotype 3, a key secondary objective for PNEU-AGE, also showed statistical significance for 15-valent vaccine (1.62; 95% CI, 1.40 – 1.87). Comparative randomized controlled trials assessing the 2 vaccines’ clinical efficacy have not been conducted.

About 4 in every 5 adult patients with IPD are aged ≥50 years old, according to Merck, with serotype 3 currently being the leading cause of IPD in adult patients in the US.

In a statement accompanying the approval, PNEU-AGE coordinating investigator Dr. Jose Cardona, of the Indago Research and Health Center, stressed the importance of bolstered protection for older adults at risk of life-threatening complications associated with IPD.

“The FDA’s approval of VAXNEUVANCE is based on robust phase 2 and 3 studies assessing immune responses in a broad range of adult populations and provides an important new option in protection from invasive pneumococcal disease,” Cardona said.

Dr. Roy Baynes, senior vice president, head of global clinical development, and chief medical officer of Merck Research Laboratories, stressed the companies’ commitment to improved preventive measures for IPD.

“That’s why we set out to develop a conjugate vaccine that includes pneumococcal serotypes that pose the greatest threat and elicits a strong immune response to each serotype covered,” Baynes said. “The FDA approval of VAXNEUVANCE builds on Merck’s more than 40 years of experience in pneumococcal disease prevention with a new option that includes serotypes responsible for substantial disease burden in adults, like serotype 3, as well as serotypes 22F and 33F, which are associated with a high degree of invasiveness and antibiotic resistance.”