September 5, 2024

EtR Framework for Adults Aged ≥65 Years Who Have Previously Received Both PCV13 and PPSV23

The Evidence to Recommendations (EtR) frameworks describe information considered in moving from evidence to ACIP vaccine recommendations.

Summary

Questions:

Should a dose of PCV20 be recommended for U.S. adults aged ≥65 years who have previously received both PCV13 and PPSV23?

Population: U.S. adults aged ≥65 years who have previously received both PCV13 and PPSV23

Intervention: PCV20

Comparison: Use of PPSV23 based on currently recommended dosing and schedule

Main Outcomes: Vaccine-type invasive pneumococcal disease; vaccine-type non-bacteremic pneumococcal pneumonia; vaccine-type pneumococcal death; serious adverse events following immunization

Setting: U.S. adults aged ≥65 years who have previously received both PCV13 and PPSV23

Background

In 2021, the 15-valent and the 20-valent pneumococcal conjugate vaccines (PCV15 and PCV20), were licensed by the FDA, and ACIP recommended the use of either PCV20 alone or PCV15 in series with the 23-valent pneumococcal polysaccharide vaccine (PPSV23), for all adults aged ≥65 years, and for adults aged 19–64 years with certain underlying medical conditions or other risk factors^*, who have not previously received a pneumococcal conjugate vaccine (PCV) or whose previous vaccination history is unknown.
At that time, adults who have previously received the 13-valent pneumococcal conjugate vaccine (PCV13) were recommended to complete their recommended vaccine series with PPSV23 since the incremental public health benefits of providing PCV15 or PCV20 to these adults had not been evaluated.

^{*Alcoholism; chronic heart, liver, or lung disease; chronic renal failure; cigarette smoking; cochlear implant; congenital or acquired asplenia; cerebrospinal fluid leak; diabetes mellitus; generalized malignancy; HIV; Hodgkin disease; immunodeficiency; iatrogenic immunosuppression; leukemia, lymphoma, or multiple myeloma; nephrotic syndrome; solid organ transplant; sickle cell disease; or other hemoglobinopathies.}

Public Health Problem

References in this table:1 2 3 4

Criteria	Work Group Judgements	Evidence	Additional Information
Is the problem of public health importance?	Yes	In adults, the burden of pneumococcal disease increases with age. Pneumococcal pneumonia is the most common type of pneumococcal disease in adults, although the estimated incidence of the disease has varied. The reported incidence of all-cause pneumonia hospitalization among U.S. adults aged ≥65 years ranges from 847–3,365 per 100,000 population^*[1]. According to a prospective multicenter surveillance study during 2013–2016, the serotypes contained in PCV13 and PCV20 caused 4.2% and 7.0%, respectively, of all-cause community-acquired pneumonia hospitalizations in adults aged ≥65 years [2]. Invasive pneumococcal disease (IPD), defined as the detection of pneumococcus in a normally sterile site such as blood or cerebrospinal fluid, is less frequent but is associated with high morbidity and mortality. According to CDC’s Active Bacterial Core surveillance (ABCs) data in 2018–2019, IPD incidence was 24 per 100,000 population with a case-fatality ratio of 14% in adults aged ≥65 years. Among all IPD cases, 27% were serotypes included in PCV13 and 29% were additional serotypes included in PCV20 (but not in PCV13). In 2014, routine use of the PCV13 was recommended for all adults aged ≥65 years, in addition to PPSV23 that had already been recommended. However, IPD incidence caused by serotypes contained in PCV13 remained stable during 2014–2019. Serotype 3 has been the most common remaining PCV13-type disease, causing 62% of IPD cases caused by PCV13 serotypes in 2018–2019. Among Medicare Part A/B beneficiaries aged ≥65 years, 47% received at least one dose of PCV13, and 30% received both PCV13 and PPSV23 (Centers for Medicare & Medicaid [CMS] unpublished data) in 2020. As of June 2022, the median time since any PCV13 vaccination was 5.6 years (range 0–8.5 years), and among those who received PCV13 followed by PPSV23, the median time since PPSV23 vaccination was 3.2 years (range 0–8.4 years; CMS unpublished data). The exact duration of protection of pneumococcal vaccines is unknown. However, a post-hoc analysis from a randomized controlled trial on PCV13 showed that there was no evidence of waning protection against vaccine-type non-bacteremic pneumococcal pneumonia or vaccine-type IPD for 4 years [3]. Data on the duration of protection of PPSV23 is available from observational studies only that reported variable results, although waning protection was reported as early as 2 years since vaccination [4].	Some Work Group members expressed that the interpretation varies depending on factors such as time since the last vaccination, age, or the presence of underlying medical conditions.

^{*Limited to studies that collected data during or after 2010, when PCV13 was introduced for use among U.S. children}

Benefits and Harms

References in this table:5 6 7 8 9

Criteria	Work Group Judgements	Evidence	Additional Information
How substantial are the desirable anticipated effects?	Small/Moderate	PCV20 contains the 13 serotypes in PCV13 and 7 additional serotypes. PPSV23 contains 4 additional serotypes that are not included in PCV20 (PPSV23 does not contain serotype 6A, which is included in PCV20). PPSV23 induces a T-cell-independent immune response that stimulates immediate B-cell responses, whereas PCVs induce a T-cell-dependent immune response [5]. As a result, PCVs have an immunologic advantage over PPSV in that T-cell dependent responses enhance B-cell responses, and that serotype-specific memory B cells are generated [5]. A systematic review of the literature showed that point estimates of the effectiveness of PCV13 against vaccine-type pneumococcal disease are generally higher compared with those of PPSV23 [6, 7]. Two studies that assessed the immunogenicity of PCV20 among adults aged ≥65 years without immunocompromising conditions (IC) who had previously received pneumococcal vaccines were identified [8, 9]. In one study, participants either received: 1) PCV13 ≥6 months previously, 2) PPSV23 1–5 years previously, or 3) both PCV13 followed by PPSV23, with PPSV23 at least 1 year previously [8]. Another was a post-hoc analysis of a Phase 3 clinical trial that assessed a subset of participants who received pneumococcal vaccines ≥6 months previously [9]. Neither study directly compared the immunogenicity of PCV20 with PPSV23 after receipt of both PCV13 and PPSV23. Opsonophagocytic activity geometric mean titers (OPA GMTs) of serotypes included in PCV20 assessed one month after PCV20 vaccination was numerically higher among those who previously received both PCV13 and PPSV23 compared with adults who previously received PPSV23 only in 19 of 20 PCV20 serotypes (statistically significantly higher for serotype 23F) in one study [8] and for 15 of 20 PCV20 serotypes (statistically significantly higher for serotypes 6B, 18C, and 23F) in another study [9]. Percent seroresponders (defined as ≥4-fold rise in OPA titer from before to 1 month after PCV20) was numerically higher for 3 of 20 serotypes in one study [8], and 6 of 20 serotypes in another [9]. None were statistically significantly higher.	The Work Group’s interpretation was split between small and moderate. Small anticipated effects Some WG members who interpreted this domain as small anticipated effects believed that the anticipated effects will be small since PCV20 does not provide broader serotype coverage for adults who have already received both PCV13 and PPSV23 and that the number of additional cases that are expected to be prevented is likely modest. Moderate anticipated effects Some WG members who interpreted this domain as moderate anticipated effects believed that protection from both PCV13 and PPSV23 will be offset by the shorter duration of protection from PPSV23 compared with PCVs. Additionally, adults with IC are likely to have inadequate immune responses and duration of protection from PPSV23. Others Some Work Group members believed that the interpretation of this EtR domain will depend on the time since vaccination, the age of the patient, and the presence of underlying medical conditions. Some believed that magnitude of desirable effects will depend on the indirect effects of pediatric PCV20 vaccination, or coverage of PCV20 among adults.
How substantial are the undesirable anticipated effects?	Minimal	One Phase 3 trial assessed the safety of PCV20 use among adults aged ≥65 years without IC who had previously received PCV13 followed by PPSV23 at least 1 year previously [8]. There was no direct comparator to this group. Percentage of participants reporting any adverse events 1 month after vaccination was 10.4%, and the percentage reporting serious adverse events through 6 months after vaccination was 1.6%. None of the serious adverse events were deemed to be vaccine related [8].
Do the desirable effects outweigh the undesirable effects?	Favors intervention	Regardless of the magnitude of the desirable anticipated effects of recommending PCV20 for this population, the Work Group felt that the undesirable anticipated effects were even smaller given the safety profile of the vaccine.	Given the high cost of the intervention, some Work Group members believed that it is important to consider the potential negative impact from the societal perspective of recommending PCV20 for adults aged ≥65 years who have already received both PCV13 and PPSV23. This concern was discussed further in the domain of “Resource Use”.
What is the overall certainty of the evidence of effects?	Effectiveness of the intervention: Moderate Safety of intervention: Moderate	GRADE analyses were completed to assess the certainty of evidence. Overall evidence type was 2 (moderate) for vaccine effectiveness. Assessment on indirectness was downgraded to “serious”: Only immunogenicity studies were available. Correlates of protection have not been established for PCV20 in adults. Overall evidence type was 2 (moderate) for serious adverse events. Assessment on imprecision was downgraded to “serious” because there were no vaccine-related serious adverse events reported in studies with small sample sizes.	Refer to GRADE summary tables for details.

Values

Criteria	Work Group Judgements	Evidence	Additional Information
Does the target population feel that the desirable effects are large relative to undesirable effects?	Probably yes	No research evidence was identified.	Since these are adults who have already received both PCV13 and PPSV23, the Work Group believed that there is probably some understanding of the importance of receiving pneumococcal vaccines and would feel that the added effects from receiving PCV20 are large relative to undesirable effects. However, some Work Group members felt that there was not enough information to make the decision, or that the interpretation will vary among the target population.
Is there important uncertainty about or variability in how much people value the main outcomes?	Variable responses among WG members	No research evidence was identified.	Some Work Group members believed that since these are adults who have already received both PCV13 and PPSV23, there is probably no important uncertainty or variability about receiving another dose of the pneumococcal vaccine. Others believed that there could be uncertainty or variability depending on the age, life expectancy, time since the last vaccination, or sequelae after pneumococcal disease.

Acceptability

References in this table:10 11

Criteria	Work Group Judgements	Evidence	Additional Information
Is the intervention acceptable to key stakehold-ers?	Probably yes	Findings from two healthcare provider (HCP) surveys were reviewed. According to a survey conducted in early 2021 among HCPs (physicians, physician assistants, nurse practitioners, pharmacists) involved in adult pneumococcal vaccination, 68% (514/712) of survey respondents either somewhat approved or strongly approved of recommending a higher-valent PCV in those who have previously received PCV13 [10]. In another HCP survey targeting physicians and pharmacists who provide pneumococcal vaccines for adults, HCPs were generally more agreeable to recommending a dose of PCV20 for adults who have received PCV13 only, compared with adults who have already received both PCV13 and PPSV23. Among adults who have already received both PCV13 and PPSV23, HCPs were more agreeable to recommending a dose of PCV20 for adults aged 19–64 years with IC compared with adults aged ≥65 years [11].

Resource Use

Criteria	Work Group Judgements	Evidence	Additional Information
Is the intervention a reasonable and efficient allocation of resources?	Variable responses among WG members	Three economic models were reviewed. These models were conducted by CDC, Merck, and Pfizer, and each model assessed PCV20 use among adults aged ≥65 years. Each model used different assumptions, which could have contributed to the differences in the results across models. All cost estimates have been adjusted to 2022 USD using the consumer price index. In the CDC model, looking at cohorts of adults aged 65 years or 75 years, who previously received PCV13 and PPSV23 and who wait 1–10 years to receive PCV20 following their most recent pneumococcal vaccine dose (10 years was not considered for the 75-year old cohort), the cost per quality-adjusted life year (QALY) gained of PCV20 ranged from 168,000 to 970,000 USD in adults without IC, and ranged from 421,000 to 925,000 USD in adults with IC. The higher cost per QALY gained in adults with IC appeared to be due to the shorter life expectancy and the lower vaccine effectiveness assumptions in adults with IC. In the Pfizer model, looking at a population where the majority of individuals were adults aged 65 years and older who previously received PCV13 and PPSV23 and who wait 7 years to receive PCV20 following their most recent pneumococcal vaccine dose, the cost per QALY gained of PCV20 use compared with no additional vaccination ranged from 93,000 to 182,000 USD per QALY gained, where the range represents results with and without indirect effects from a childhood program. The Pfizer model aggregated ages and populations, the average age was 72 years and included adults both with and without IC. In the Merck model, looking at a cohort of adults aged 68, who previously received PCV13 and PPSV23 and who wait 5 years to receive PCV20 following their most recent pneumococcal vaccine dose, the cost per QALY gained of PCV20 use was 217,000 USD in adults with no IC. In general, the cost per QALY gained was lower if there were longer intervals since the last pneumococcal vaccine dose and was lower if age was increased. As an example, from the CDC model, for a person aged 76 years without an IC receiving PCV20 after 10 years following completion of the PCV13 and PPSV23 series, the cost per QALY gained ranged from 181,000 to 293,000 USD, which was lower than for a person aged 77 years without an IC receiving PCV20 after 1 year following completion of the PCV13 and PPSV23 series, where the cost per QALY gained ranged from 322,000 to 355,000 USD.	Additional details on economic models The variations in results across the models appear likely to be due to differences in selected assumptions across the models. Relative to the CDC model, the Pfizer model base case included several assumptions that could have contributed to differences in results across models, including: A higher vaccine effectiveness of PCVs (PCV13, PCV20) against pneumococcal disease due to serotype 3. Serotype 3 is the most common cause of remaining PCV13-type disease. PPSV23 had no effectiveness against pneumococcal pneumonia. Assumed higher QALY loss for invasive pneumococcal disease and hospitalized pneumococcal pneumonia. Longer time period between previous vaccination and PCV20 use. Relative to the CDC model, the Merck model included several assumptions that could have contributed to differences in results across models, including: Case fatality ratios from hospitalized pneumococcal pneumonia among adults aged ≥65 years were higher. Indirect effects were not included. Work group interpretations The Work Group’s interpretation of this domain was variable. Probably Yes Some Work Group members believed that the benefit of recommending PCV20 still outweighed the cost. Probably No Some believed that the added benefit from recommending PCV20 for adults who have already received PCV13 and PPSV23 is likely too small to justify the use of resources. Varies Some believed that the interpretation will depend on the time since the last vaccination, age, presence of underlying medical conditions, and functional status.

Criteria

Work Group Judgements

Evidence

Additional Information

Is the intervention a reasonable and efficient allocation of resources?

Variable responses among WG members

Three economic models were reviewed. These models were conducted by CDC, Merck, and Pfizer, and each model assessed PCV20 use among adults aged ≥65 years. Each model used different assumptions, which could have contributed to the differences in the results across models. All cost estimates have been adjusted to 2022 USD using the consumer price index.

In the CDC model, looking at cohorts of adults aged 65 years or 75 years, who previously received PCV13 and PPSV23 and who wait 1–10 years to receive PCV20 following their most recent pneumococcal vaccine dose (10 years was not considered for the 75-year old cohort), the cost per quality-adjusted life year (QALY) gained of PCV20 ranged from 168,000 to 970,000 USD in adults without IC, and ranged from 421,000 to 925,000 USD in adults with IC. The higher cost per QALY gained in adults with IC appeared to be due to the shorter life expectancy and the lower vaccine effectiveness assumptions in adults with IC.

In the Pfizer model, looking at a population where the majority of individuals were adults aged 65 years and older who previously received PCV13 and PPSV23 and who wait 7 years to receive PCV20 following their most recent pneumococcal vaccine dose, the cost per QALY gained of PCV20 use compared with no additional vaccination ranged from 93,000 to 182,000 USD per QALY gained, where the range represents results with and without indirect effects from a childhood program. The Pfizer model aggregated ages and populations, the average age was 72 years and included adults both with and without IC.

In the Merck model, looking at a cohort of adults aged 68, who previously received PCV13 and PPSV23 and who wait 5 years to receive PCV20 following their most recent pneumococcal vaccine dose, the cost per QALY gained of PCV20 use was 217,000 USD in adults with no IC.

In general, the cost per QALY gained was lower if there were longer intervals since the last pneumococcal vaccine dose and was lower if age was increased. As an example, from the CDC model, for a person aged 76 years without an IC receiving PCV20 after 10 years following completion of the PCV13 and PPSV23 series, the cost per QALY gained ranged from 181,000 to 293,000 USD, which was lower than for a person aged 77 years without an IC receiving PCV20 after 1 year following completion of the PCV13 and PPSV23 series, where the cost per QALY gained ranged from 322,000 to 355,000 USD.

Additional details on economic models

The variations in results across the models appear likely to be due to differences in selected assumptions across the models. Relative to the CDC model, the Pfizer model base case included several assumptions that could have contributed to differences in results across models, including:

A higher vaccine effectiveness of PCVs (PCV13, PCV20) against pneumococcal disease due to serotype 3. Serotype 3 is the most common cause of remaining PCV13-type disease.
PPSV23 had no effectiveness against pneumococcal pneumonia.
Assumed higher QALY loss for invasive pneumococcal disease and hospitalized pneumococcal pneumonia.
Longer time period between previous vaccination and PCV20 use.

Relative to the CDC model, the Merck model included several assumptions that could have contributed to differences in results across models, including:

Case fatality ratios from hospitalized pneumococcal pneumonia among adults aged ≥65 years were higher.
Indirect effects were not included.

Work group interpretations

The Work Group’s interpretation of this domain was variable.

Probably Yes

Some Work Group members believed that the benefit of recommending PCV20 still outweighed the cost.

Probably No

Some believed that the added benefit from recommending PCV20 for adults who have already received PCV13 and PPSV23 is likely too small to justify the use of resources.

Varies

Some believed that the interpretation will depend on the time since the last vaccination, age, presence of underlying medical conditions, and functional status.

Equity

References in this table:12 13

Criteria	Work Group Judgements	Evidence	Additional Information
What would be the impact of the intervention on health equity?	Probably increased/probably no impact	Disparities in pneumococcal disease burden The introduction of PCV13 among children reduced the disparities that existed in PCV13-type IPD incidence among racial groups [12], likely due to the indirect effects of PCV13 use in children. However, Black adults continue to have higher IPD incidence compared with White adult, due to non-PCV13 type disease, in particular serotypes not contained in PCV20. Disparities in pneumococcal vaccine coverage An analysis of PCV13 and PPSV23 claims data of Medicare beneficiaries aged ≥65 years showed that in 2019, the proportion of beneficiaries who received at least one dose of PCV13 was the highest in White adults (51%) and lowest in Hispanic adults (30%) [13]. The proportion who received both PCV13 and PPSV23 was also the highest in White adults (33.9%) and the lowest in Hispanic adults (16%) [13].	The Work Group’s interpretation of this domain was variable. Increased or probably increased health equity Recommending the use of PCV20 will decrease the disparities in pneumococcal disease burden that exist since conditions that increase the risk of pneumococcal disease are disproportionately represented in non-White populations. Access to preventive measures like vaccines is likely better for minority populations compared with access to care for the disease. Probably no impact on health equity Access and utilization of the vaccine are likely to follow existing patterns so there will be no impact on health equity. The added benefit of recommending PCV20 to adults who have already received PCV13 and PPSV23 will be small. Reduced/probably reduced health equity A minority believed that the new recommendation will likely be adopted more rapidly among those who already have good access to care and will make the existing disparities more pronounced.

Criteria

Work Group Judgements

Evidence

Additional Information

What would be the impact of the intervention on health equity?

Probably increased/probably no impact

Disparities in pneumococcal disease burden

The introduction of PCV13 among children reduced the disparities that existed in PCV13-type IPD incidence among racial groups [12], likely due to the indirect effects of PCV13 use in children. However, Black adults continue to have higher IPD incidence compared with White adult, due to non-PCV13 type disease, in particular serotypes not contained in PCV20.

Disparities in pneumococcal vaccine coverage

An analysis of PCV13 and PPSV23 claims data of Medicare beneficiaries aged ≥65 years showed that in 2019, the proportion of beneficiaries who received at least one dose of PCV13 was the highest in White adults (51%) and lowest in Hispanic adults (30%) [13]. The proportion who received both PCV13 and PPSV23 was also the highest in White adults (33.9%) and the lowest in Hispanic adults (16%) [13].

The Work Group’s interpretation of this domain was variable.

Increased or probably increased health equity

Recommending the use of PCV20 will decrease the disparities in pneumococcal disease burden that exist since conditions that increase the risk of pneumococcal disease are disproportionately represented in non-White populations. Access to preventive measures like vaccines is likely better for minority populations compared with access to care for the disease.

Probably no impact on health equity

Access and utilization of the vaccine are likely to follow existing patterns so there will be no impact on health equity. The added benefit of recommending PCV20 to adults who have already received PCV13 and PPSV23 will be small.

Reduced/probably reduced health equity

A minority believed that the new recommendation will likely be adopted more rapidly among those who already have good access to care and will make the existing disparities more pronounced.

Feasibility

References in this table:14 15

Criteria	Work Group Judgements	Evidence	Additional Information
Is the intervention feasible to implement?	Probably yes	According to a survey among members of the Association of Immunization Managers conducted in September 2022, 26% (6 of 23) responded that their jurisdiction’s health department currently offers PCV13 for adults, and 36% (9/23) responded that their jurisdiction’s health department currently offers PCV20 for adults. Regarding what members saw as the major challenge with the adult pneumococcal vaccine program, 61% (14/23) reported a lack of funding to support the health department’s adult pneumococcal vaccine program and 17% (4/23) reported complicated recommendations [14]. An HCP survey by Merck targeting physicians, pharmacists, and physician assistants showed that HCPs know when a pneumococcal vaccine was given to their patients 56% of the time and which vaccine was given 58% of the time [15].	Most Work Group members believed that recommending PCV20 for adults who previously received pneumococcal vaccines is simple enough to implement. Since pneumococcal vaccination history is often hard to obtain, some Work Group members believed that there will be less guesswork involved to ensure that patients are up to date with pneumococcal vaccines. Others believed that feasibility would depend on electronic medical record decision support and improvement in adult vaccine registries so that all vaccines that patients received are reported in a single registry.

Balance of consequences

Desirable consequences probably outweigh undesirable consequences in most settings

Some Work Group members believed that the public health benefit of recommending PCV20 for adults who have already received both PCV13 and PPSV23 is marginal and that the evidence is not as compelling as recommending PCV15 or PCV20 for adults who have not previously received any pneumococcal vaccines. In addition, PCV20 may be recommended for use among children in the near future, and new pneumococcal vaccines are currently under development. Therefore, the added benefit of PCV20 use among adults may be time limited. However, the Work Group members acknowledged that the magnitude of the desirable consequences depends on the time since vaccination, age, and underlying conditions of the patient, and some patients are likely to benefit from receiving PCV20.

View the complete list of EtR Frameworks‎‎‎

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September 5, 2024

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Content Source:

National Center for Immunization and Respiratory Diseases (NCIRD)

References

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