Pneumococcal Vaccine Naïve Adults 18 Years of Age and Older

The safety of Prevnar 20 in adults 18 years of age and older with no history of pneumococcal vaccination was evaluated in five studies (Studies 1–5). In the main cohort of Study 1 (NCT03760146) and in Study 2 (NCT03313037), participants ≥60 years of age and participants 60 through 64 years of age, respectively, received a single dose of Prevnar 20 followed 1 month later with administration of saline placebo or received a single dose of Prevnar 13 followed 1 month later with a dose of PNEUMOVAX® 23 (PPSV23). The 2 other cohorts of Study 1, participants 50 through 59 years of age and participants 18 through 49 years of age, received a single vaccination with Prevnar 20 or Prevnar 13. In Study 3 (NCT03828617), participants 18 through 49 years of age received a single vaccination with Prevnar 20 or Prevnar 13. In Studies 4 (NCT02955160) and 5 (NCT03642847), which were smaller studies conducted early in the clinical development of Prevnar 20, participants 18 through 49 years of age received a single dose of Prevnar 20 or an active control (Tdap or Prevnar 13).

Adults ≥65 Years of Age (Pneumococcal Vaccine Naïve or Previously Immunized with a Pneumococcal Vaccine)

The safety of Prevnar 20 in adults 65 years of age and older with pneumococcal vaccination given as routine care prior to enrollment was assessed in Study 6 (NCT03835975). Participants were enrolled into 1 of 3 cohorts based on their prior pneumococcal vaccination history (PPSV23 only ≥1 to ≤5 years prior to enrollment, Prevnar 13 only ≥6 months prior to enrollment, or Prevnar 13 followed by PPSV23 [with PPSV23 given ≥1 year prior to enrollment]). Participants in 2 of the cohorts received a single vaccination with Prevnar 20 or control pneumococcal vaccine (Prevnar 13), and the other cohort received a single vaccination with Prevnar 20. only.

The safety of Prevnar 20 in adults 65 years of age and older when coadministered with Influenza Vaccine, Adjuvanted (Fluad Quadrivalent) was assessed in Study 7 (NCT 04526574). Randomization was stratified by prior pneumococcal vaccine status (no previous pneumococcal vaccine, receipt of at least 1 dose of PPSV23 only, receipt of at least 1 dose of Prevnar 13 only, or receipt of at least 1 dose each of PPSV23 and Prevnar 13). Participants were randomized in a 1:1 ratio to receive Prevnar 20 concomitantly administered with Fluad Quadrivalent (Group 1) or Fluad Quadrivalent followed approximately one month later by Prevnar 20 (Group 2).

Demographics of Trial Participants

In the three main trials (Studies 1, 3, and 6), participants were predominantly female (52.0% to 65.9%) across groups defined by age and prior pneumococcal vaccination status within the Prevnar 20 and control vaccine groups. Across all 3 trials combined, 59.8% of participants were 60 years of age and older, 6.9% were 50 through 59 years of age, and 33.3% were 18 through 49 years of age. In Studies 1 and 3, participants were 80.7% White, 14.2% Black, 2.1% Asian, and 10.3% Hispanic. In Study 6, participants were predominantly White (92.4%). Participants were primarily from the United States; however a portion of participants 65 years of age and older were enrolled from Sweden in Study 1 (5.7% of participants 60 years of age and older in that study) and also in Study 6 (35.5% of participants with prior PPSV23 only). In Study 7, 54.7% of participants were female. The mean age of participants was 72 years (range 65–103 years). Participants were 90.6% White, 6.9% Black, 1.2% Asian, and 9.4% Hispanic.

In the three main trials, participants with pre-existing underlying diseases were enrolled if the medical condition was stable (did not require a significant change in therapy in the 6 weeks before receipt of study vaccine or any hospitalization for worsening disease within 12 weeks before receipt of study vaccine). In Study 1, approximately one-third of all participants had risk factors that placed them at increased risk for serious pneumococcal disease, including smoking (12.9%), stable medical conditions of chronic cardiovascular disease (5.5%), chronic pulmonary disease including asthma (8.7%), chronic liver disease (0.4%), and diabetes mellitus (13.9%).

Safety Monitoring

Solicited adverse reactions for Prevnar 20 in the three main trials and Study 7 were monitored in participants recording daily into an electronic diary their local adverse reactions for 10 consecutive days and systemic reactions for 7 consecutive days following vaccination. Across all trials, serious and nonserious adverse events were collected for 1 month after each vaccination. Safety follow-up of serious adverse events (SAEs) continued through 6 months after vaccination with Prevnar 20 or Prevnar 13 (or other appropriate control vaccine), as applicable. Newly diagnosed chronic medical conditions occurring within 6 months after vaccination were also collected via telephone contact.

Serious Adverse Events (Studies 1 through 6)

Across studies 1 through 6, performed in adults of all ages, naïve to and with prior pneumococcal vaccination, the proportion of participants reporting 1 or more SAEs within 6 months after vaccination with Prevnar 20 was 1.5% (67 of 4552 participants). This was similar to the proportion of participants with SAEs after vaccination with Prevnar 13 or other applicable control vaccine (1.8%, 44 of 2496). The proportions of participants with SAEs occurring within 1 month after vaccination with Prevnar 20 or with Prevnar 13 or other applicable control vaccine were both 0.4% (19 of 4552 participants and 11 of 2496 participants, respectively). There were no notable patterns or imbalances between vaccine groups for specific categories of serious adverse events that would suggest a causal relationship to Prevnar 20.

Solicited Adverse Reactions

The frequency and severity of the local adverse reactions (redness, swelling, and pain at the injection site) prompted daily in the 10 days after Prevnar 20 vaccination in adults naïve to pneumococcal vaccination (Study 1) and in adults with prior pneumococcal vaccination (Study 6) are shown in Table 1 and Table 2, respectively. The frequency and severity of the systemic adverse reactions (fever, fatigue, headache, muscle pain, and joint pain) prompted daily in the 7 days after Prevnar 20 vaccination in adults naïve to pneumococcal vaccination (Study 1) and in adults with prior pneumococcal vaccination (Study 6) are shown in Table 3 and Table 4, respectively.

Safety with Concomitant Vaccine Administration in Adults ≥65 years of age

In Study 7, the rates of local reactions at the Prevnar 20 injection site within 10 days after vaccination were similar between participants who received Prevnar 20 and Fluad Quadrivalent concomitantly (Group 1) or separately (Group 2). The rates of systemic reactions within 7 days following administration of Prevnar 20 were generally numerically higher in Group 1 compared to Group 2; however, overall, fever in both groups was uncommon (<1.5%) and other systemic reactions (fatigue, headache, muscle, or joint pain) were primarily mild to moderate (≤0.9% were severe). The proportions of participants with SAEs occurring within 1 month after vaccination with Prevnar 20 were 1.1% for Group 1 and 1.7% in Group 2. No SAEs occurring within 1 month after vaccination with Prevnar 20 were considered related to vaccination.

Risk Summary

All pregnancies have a risk of birth defect, loss, or other adverse outcomes. In the US general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. There are no adequate and well-controlled studies of Prevnar 20 in pregnant women. Available data on Prevnar 20 administered to pregnant women are insufficient to inform vaccine-associated risks in pregnancy.

A developmental toxicity study was performed in female rabbits administered Prevnar 20 prior to mating and during gestation. The dose was 0.5 mL at each occasion (a single human dose is 0.5 mL). This study revealed no evidence of harm to the fetus due to Prevnar 20 (see Data).

Data

Risk Summary

It is not known whether Prevnar 20 is excreted in human milk. Data are not available to assess the effects of Prevnar 20 on the breastfed infant or on milk production/excretion. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for Prevnar 20 and any potential adverse effects on the breastfed child from Prevnar 20 or from the underlying maternal condition. For preventive vaccines, the underlying maternal condition is susceptibility to disease prevented by the vaccine.

Immunogenicity of Prevnar 20 in Pneumococcal Vaccine Naïve Adults

Prevnar 20 effectiveness against invasive pneumococcal disease caused by the 20 vaccine serotypes and against pneumonia caused by the 13 serotypes in Prevnar 13 was inferred from comparative immunogenicity to US-licensed pneumococcal vaccines (Prevnar 13 and PPSV23). Study 1, conducted in the United States and Sweden, was designed to evaluate immunologic noninferiority of Prevnar 20 to Prevnar 13 (for the 13 original S. pneumoniae serotypes) and PPSV23 (for the 7 new S. pneumoniae serotypes) in pneumococcal vaccine naive adults ≥60 years of age. Immune responses elicited by Prevnar 20 and the control pneumococcal vaccines were measured by an OPA assay. OPA assays were used to measure functional antibodies to S. pneumoniae.

Study 1 included healthy adults and immunocompetent adults with stable underlying conditions, including chronic cardiovascular disease, chronic pulmonary disease, renal disorders, diabetes mellitus, chronic liver disease, and medical risk conditions and behaviors (e.g., smoking) that are known to increase the risk of serious pneumococcal pneumonia and IPD. A stable medical condition was defined as a medical condition not requiring significant change in therapy in the previous 6 weeks (i.e., change to new therapy category due to worsening disease) or any hospitalization for worsening disease within 12 weeks before receipt of the study vaccine.

Comparison of Immune Responses of Prevnar 20 to Prevnar 13 and PPSV23 in Pneumococcal Vaccine Naïve Adults ≥60 Years of Age

In a randomized, active-controlled, double-blind noninferiority clinical trial (Study 1) of Prevnar 20 in the United States and Sweden, pneumococcal vaccine -naïve adults 18 years of age and older were enrolled into 1 of 3 cohorts based on their age at enrollment and randomized to receive either Prevnar 20 or control. Participants 60 years of age and older were randomly assigned (1:1 ratio) to Prevnar 20 followed 1 month later with saline placebo or to Prevnar 13 followed 1 month later with PPSV23.

Serotype-specific OPA GMTs were measured before the first vaccination and 1 month after each vaccination. Noninferiority of immune responses, OPA GMTs 1 month after vaccination, with Prevnar 20 to a control vaccine for a serotype was declared if the lower bound of the 2 sided 95% CI for the GMT ratio (Prevnar 20/Prevnar 13; Prevnar 20/PPSV23) for that serotype was greater than 0.5.

In adults 60 years of age and older, immune responses to all 13 matched serotypes elicited by Prevnar 20 were noninferior to the immune responses to the serotypes elicited by Prevnar 13 one month after vaccination. Immune responses to 6 out of the 7 additional serotypes induced by Prevnar 20 were noninferior to the immune responses to these same serotypes induced by PPSV23 one month after vaccination. The response to serotype 8 missed the prespecified statistical noninferiority criterion by a small margin (the lower bound of the 2-sided 95% CI for the GMT ratio being 0.49 versus >0.50) (Table 6).

In supportive analyses, 77.8% of participants in the Prevnar 20 group achieved a ≥4-fold rise in serotype 8 OPA titers from before vaccination to 1 month post-vaccination.

Immunobridging in Pneumococcal Vaccine Naïve Adults 18 Through 59 Years of Age

In Study 1 (described above), the effectiveness of Prevnar 20 in adults 50 through 59 years of age and in adults 18 through 49 years of age was inferred following comparison of the immune response to each of the 20 vaccine serotypes in each of these age groups to the corresponding serotype-specific immune responses in adults 60 through 64 years of age following Prevnar 20 (immunobridging). In Study 1, pneumococcal vaccine-naïve participants 50 through 59 years of age and 18 through 49 years of age were randomly assigned (3:1 ratio) to receive 1 vaccination with Prevnar 20 or Prevnar 13. Serotype-specific OPA GMTs were measured before vaccination and 1 month after vaccination. A comparative analysis of Prevnar 20 in the younger age group versus Prevnar 20 in adults 60 through 64 years of age for each vaccine serotype was performed to support the indication in adults 18 through 49 years of age and 50 through 59 years of age. Immunobridging was to be declared successful if the lower bound of the 2-sided 95% CI for the GMT ratio (Prevnar 20 in participants 18 through 49 years of age/60 through 64 years of age and in participants 50 through 59 years of age/60 through 64 years of age) for the 20 serotypes was >0.5 (2-fold). Prevnar 20 elicited serotype-specific immune responses to each of the 20 vaccine serotypes in both of the younger age groups that were within 2-fold of the corresponding serotype-specific responses in adults 60 through 64 years of age, when measured 1 month after vaccination (Table 7).

Immunogenicity of Prevnar 20 in Adults Previously Vaccinated With Pneumococcal Vaccine

A randomized, open-label clinical trial (Study 6) described immune responses to Prevnar 20 in adults 65 years of age and older previously vaccinated with PPSV23 (≥1 to ≤5 years prior to enrollment), previously vaccinated with Prevnar 13 (≥6 months prior to enrollment), or previously vaccinated with Prevnar 13 followed by PPSV23 (with PPSV23 vaccination ≥1 year prior to enrollment). Participants in this clinical trial previously vaccinated with Prevnar 13 (Prevnar 13 only or followed by PPSV23) were enrolled at sites in the United States and participants previously vaccinated with PPSV23 only were also enrolled from Swedish sites (35.5% in that category). Immune responses elicited by Prevnar 20 were measured by an OPA assay.

OPA GMTs in participants who received PPSV23 1 to 5 years prior to Prevnar 20 were diminished compared to OPA GMTs in participants who received Prevnar 13 at least 6 months previously and compared to OPA GMTs in participants who received Prevnar 13 followed by PPSV23, with the last PPSV23 dose given at least 1 year prior to Prevnar 20.

Clinical Trial in Adults to Assess Prevnar 20 Given With Influenza Vaccine, Adjuvanted (Fluad Quadrivalent)

Study 7 was a double-blind, randomized study conducted in adults 65 years of age and older who had no history of prior pneumococcal vaccination or who had previously received PPSV23 and/or Prevnar 13 at least 6 months prior to enrollment. Study participants were randomized in a 1:1 ratio to receive Prevnar 20 concomitantly administered with Fluad Quadrivalent followed approximately one month later by placebo (Group 1, N=898) or Fluad Quadrivalent concomitantly administered with placebo followed approximately one month later by Prevnar 20 (Group 2, N=898). Pneumococcal serotype-specific OPA GMTs were evaluated 1 month after Prevnar 20 and influenza vaccine strain hemagglutinin inhibition assay (HAI) GMTs were evaluated 1 month after Fluad Quadrivalent. The noninferiority criteria for the comparisons of OPA GMTs (lower limit of the 2- sided 95% CI of the GMT ratio [Group 1/Group 2] >0.5, 2-fold noninferiority criterion) were met for all 20 pneumococcal serotypes in Prevnar 20. The noninferiority criteria for the comparisons of HAI GMTs (lower limit of the 2- sided 95% CI for the GMT ratio [Group 1/Group 2] >0.67, 1.5-fold noninferiority criterion) were also met for all 4 influenza vaccine strains.